EPA Report No. 600/R-01/035
                                              April 2001
Bioaccumulation and Aquatic
   System Simulator (BASS)
          User's Manual
     Beta Test Version 2.1
                   by
               M. Craig Barber
           Ecosystems Research Division
         U.S. Environmental Protection Agency
            960 College Station Road
            Athens, GA 30605-2700
        National Exposure Research Laboratory
         Office of Research and Development
         U.S. Environmental Protection Agency
         Research Triangle Park, NC 27711

-------
                                                    Notice
The research described in this document was funded by the U.S. Environmental Protection Agency through the Office of
Research and Development. The research described herein was conducted at the Ecosystems Research Division of the USEPA
National Exposure Research Laboratory in Athens, Georgia. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.

-------
                                                    Foreword
This report describes the theoretical development, parameterization, and application software of a generalized, community-based,
bioaccumulation model called BASS (Bioaccumulation and Aquatic System Simulator). This model is designed to predict the
population and bioaccumulation dynamics of age-structured fish communities that are exposed to hydrophobic organic chemicals and
class B and borderline metals that complex with sulfhydryl groups (e.g., cadmium, copper, lead, mercury, nickel, silver, and zinc).
This report is not a case study on the application of BASS but rather a reference and user's guide. The intended audience of this report
and associated software is research fisheries ecologists, bioaccumulation researchers, and EPA environmental scientists and ecologists
who must routinely analyze and estimate bioaccumulation of chemicals in fish for ecological or human health exposure assessments.

BASS version 2.1 is a beta test version that is being released on a targeted basis to EPA Program and  Regional Offices and to the
academic research community for comment and testing. Although the model has not been extensively field-tested, its process-based
algorithms for predicting chemical bioaccumulation, growth of individual fish, predator-prey interactions, and population dynamics
either have been corroborated or have been formulated using widely accepted ecological and ecotoxicological principles. Even when
a process-based model has undergone only limited field testing, it canbe an extremely useful tool. Process-based models enable users
to observe quantitatively the results of a particular abstraction of the real world. Moreover, such models can be argued to be the only
objective method to make extrapolations to unobserved or unobservable conditions. If the conceptualization and construction of
process-based models are both comprehensive (i.e., holistic) and reasonable, then their output, validated or not, can still be used for
comparative analyses. A model's ability to simulate trends and comparative dynamics are, in fact, often more important measures of
a model's utility than is its ability  to replicate a specific field or laboratory study. Although BASS  canbe used to analyze results from
actual field studies, its principal intended use is to predict and compare the outcomes of alternative management options that are
associated with pollution control  or ecosystem management or restoration activities.
                                                                         Rosemarie C. Russo, Ph.D.
                                                                         Director
                                                                         Ecosystems Research Division
                                                                         Athens, Georgia
                                                          in

-------
                                                     Abstract
BASS  (Bioaccumulation and Aquatic System Simulator) is a Fortran 95  simulation program that predicts the population and
bioaccumulation dynamics of age-structured fish assemblages that are exposed to hydrophobic organic pollutants and class B and
borderline metals that complex with sulfhydryl groups (e.g., cadmium, copper, lead, mercury, nickel, silver, and zinc). The model's
bioaccumulation algorithms are based on diffusion kinetics and are coupled to a process-based model for the growth of individual
fish. The model's exchange algorithms consider both biological attributes of fishes and physico-chemical properties of the chemicals
of concern that determine diffusive exchange across gill membranes and intestinal mucosa. Biological characteristics used by the
model include the fish's gill morphometry, feeding and growth rate, and proximate composition (i.e., its fractional aqueous, lipid, and
structural organic content). Relevant physico-chemical properties are the chemical's aqueous diffusivity, n-octanol/water partition
coefficient (Kow), and, for metals, binding coefficients to proteins and other organic matter. BASS simulates the growth of individual
fish using a standard mass balance, bioenergetic model (i.e., growth = ingestion - egestion - respiration - specific dynamic action -
excretion). A fish's realized ingestion is calculated from its maximum consumption rate adjusted for the availability of prey of the
appropriate size and taxonomy. The community' s food web is specified by defining one or more foraging classes for each fish species
based on either its body weight, body length, or age. The dietary composition of each of these feeding classes is specified as a
combination of benthos, incidental terrestrial insects, periphyton/attached algae, phytoplankton, zooplankton, and one or more fish
species. Population dynamics are generated by predatory mortalities defined by community's food web and standing stocks, size
dependent physiological mortality rates, the maximum longevity of species, and lexicological responses to chemical exposures. The
model's temporal and spatial scales of resolution are a day and a hectare, respectively. Currently, BASS ignores the migration offish
into and out of the simulated hectare.
                                                          IV

-------
                                             Table of Contents

Abstract  	iv

Figures	vii

Tables	vii

1. Introduction	 1

2. Model Formulation  	4
        2.1. Modeling Internal Distribution of Chemicals	4
        2.2. Modeling Exchange from Water	 5
        2.3. Modeling Exchange from Food  	7
        2.4. Modeling Chemical Biotransformation  	 9
        2.5. Modeling Temperature Effects on Physiological Rates 	 9
        2.6. Modeling Growth of Fish	 10
        2.7. Modeling Trophic Interactions and Predatory Mortalities	 11
        2.8. Modeling Non Predatory Mortalities and Recruitment	 13
        2.9. Modeling Toxicological Effects	 14

3. Model Parameterization	 18
        3.1. Parameterizing Kf	 18
        3.2. Parameters for Gill Exchange	 18
        3.3. Bioenergetic and Growth Parameters	 19

4. BASS User Guide  	 31
        4.1. Summary of New Features Available  in BASS version 2.1	 31
        4.2. Input File Structure	 32
                4.2.1. Simulation Control Commands	 33
                4.2.2. Chemical Input Commands	 35
                4.2.3. Fish Input Commands	 38
                4.2.4. Units Recognized by BASS	41
                4.2.5. Syntax for User Specified Functions	41
                4.2.6. User Supplied Exposure Files	42
        4.3. Output Files Generated by BASS	43
        4.4. Include Files and General File Management	43
        4.5. Command Line Options 	45
        4.6. Restrictions and Limitations	45

5. Software Installation and Management	 50
        5.1. MS-DOS Installation  	 50
        5.2. Auxiliary Software	 51

6. Example Application	 52

7. Model Quality Assurance	 54
        7.1. Questions Regarding QA of a Model's Scientific Foundations	 54
        7.2. Questions Regarding QA of a Model's Implementation 	 55
        7.3. Questions Regarding QA of Model Documentation and Applications 	 59

8. Planned Future Features	60

-------
References  	61

APPENDICES	79
        APPENDIX A. Equilibrium complexation model for metals  	79
        APPENDIX B. Nondimensionalization of chemical exchange equations for fish gills	 82
        APPENDIX C. Derivation of the consistency condition for feeding electivities	 83
        APPENDIX D. Example project file constructed using include files as discussed in Section 4.4 	 84
        APPENDIX E. Example output file (filename.msg) that summarizes user input data, input data errors, and run time
               warnings and errors	 95
        APPENDIX F. Example output file (filename.bss) that tabulates annual bioenergetic and contaminant fluxes	  112
        APPENDIX G. Example output file (filename.plx) that plots the variables requested by the user	  122
                                                      VI

-------
                                                    Figures

Figure 1. Application of Eq.(2-51) to describe the temperature dependence of the maximum daily consumption of brown trout
        (Salmo trutta) based on Elliott (1976b, Tables 2 and 9)	  17
Figure 2. First eigenvalue for Eq.(2-28) as a function of gill Sherwood number and ventilation/perfusion ratio	27
Figure 3. Second eigenvalue for Eq.(2-28)  as a function of gill Sherwood number and ventilation/perfusion ratio	28
Figure 4. First bulk mixing cup coefficient for Eq.(2-28) as a function of gill Sherwood number and ventilation/perfusion ratio.29
Figure 5. Second bulk mixing cup coefficient for Eq.(2-28) as a function of gill Sherwood number and ventilation/perfusion
        ratio	  30
Figure 6. Conceptual model for the primary food web of Everglades open water fish assemblage	  53

                                                     Tables

Table 1. Symbols used for model development	  16
Table 2. Summary of allometric coefficients and exponents for gill area and lamellar density for freshwater bony fishes and
        agnatha	20
Table 3. Summary of allometric coefficients and exponents for gill area and lamellar density for cartilaginous and marine boney
        fishes	22
Table 4. Summary of allometric coefficients and exponents for gill area and lamellar density for air-breathing fishes	23
Table 5. Summary of coefficients and exponents for lamellar lengths	24
Table 6. Summary of studies reporting water-blood barrier thickness for freshwater and marine fishes	25
Table 7. Sources of bioenergetic and growth for selected fish species	26
Table 8. Valid Unit Prefixes  	46
Table 9. Valid Unit Names for Length, Area, Volume, Mass, Time, and Energy	47
Table 10. Valid Ecological, Morphometric, and Physiological Unit Names	49
                                                        vn

-------
                                                 1. Introduction
Fish health can be defined from both an ecological and a human
health/value perspective in a wide variety of ways. Questions
relating to fish health from an ecological perspective often
include:

1)      Is individual fish growth and condition sufficient to
        enable them to  survive  periods of  natural (e.g.,
        overwintering) and man induced stress?
2)      Are individual fish species able to maintain sustainable
        populations? For  example,  is   individual growth
        adequate for the fish to attain it's minimum body size
        required for reproduction? Is there adequate physical
        environment for  successful  spawning?  Is  there
        adequate physical habitat for the survival of the young-
        of-year?
3)      Do regional fish assemblages  exhibit their expected
        biodiversity  or  community  structure  based  on
        biogeographical and physical chemical considerations?
4)      Are regional fish assemblages  maintaining their
        expected   level   of   productivity  based  on
        biogeographical and physical chemical considerations?
5)      Are appropriately sized fish abundant  enough  to
        maintain piscivorous wildlife (e.g., birds, mammals,
        and reptiles)  during  breeding  and  non-breeding
        conditions?
6)      Are potential fish prey sufficiently free of contaminants
        (endocrine disrupters, heavy metals, etc.) so as not to
        interfere   with the  growth  and  reproduction  of
        piscivorous wildlife?

From a human health or use perspective another important
question related to fish health is:

7)      Is the fish community/assemblage of concern fishable?
        That is are target fish species sufficiently abundant and
        of the desired quality?  Fish quality is this context is
        often defined in terms of desired body sizes (e.g., legal
        or  trophy  length)  and  the  absence  of  chemical
        contaminants.

Some of the important  metrics  or indicators that have been
typically used to  assess such questions include  1) physical
habitat dimensions,  e.g., bottom type and cover, occurrence of
structural elements such as woody debris or sand bars, mean and
peak current velocities,  water temperature, sediment loading,
etc., 2)  community species and functional diversity, 3) total
community biomass (kg/ha or kg/km), 4) the population density
(fish/ha or  fish/km)  or biomass  (kg/ha  or kg/km)  of  the
community's dominant species, 5) the age or size class structure
of the community's dominant species, 6) annual productivity of
the community and its dominant species, 7) individual growth
rates or condition factors (i.e., the fish's current body weight
normalized to an expected body weight based on its current
length), and 8) levels of chemical contaminants in muscle or
whole  fish for human  or ecological exposure assessments,
respectively.

From the perspective of  evaluating alternative management
options orof assessing expected future consequences of existing
conditions, simulation models that can predict the individual and
population growth of fish  and their patterns of  chemical
bioaccumulation are important tools for analyzing several of the
dimensions of fish health identified above.

Although the growth of individual fish has often been described
using empirical models  such as the  von Bertalanffy, logistic,
Gompertz, or Richards models (see for example Ricker (1979)
and Schnute (1981)), process-basedbioenergetic models such as
those described by Kitchell et al. (1977), Minton and McLean
(1982), Stewart et al. (1983), Cuenco et al. (1985), Stewart and
Binkowski (1986), Beauchamp et al.  (1989), Stewart and Ibarra
(1991), Lantry and Stewart (1993), Rand et al. (1993), Roell and
Orth (1993), Hartman and Brandt (1995a),  Petersen and Ward
(1999),  Rose et  al. (1999) , Schaeffer  et  al.  (1999), are
becoming the models of choice for predicting the growth of fish.
Because these models predict fish growth as the mass or energy
balance of ingestion, egestion, respiration, specific dynamic
action, and  excretion, they  can generally be parameterized
independently of their current application. Moreover, because of
the inherent  difficulties  in obtaining reliable  field-based
measurements of the population dynamics  and productivity of
fish, researchers are increasingly using suchbioenergetic models
to characterize these population and community level endpoints.
See for example Stewart and Ibarra (1991)  and Roell and Orth
(1993).

The ability  to predict  accurately  the bioaccumulation  of
chemicals in  fish has  become an essential component  in
assessing the ecological and human health risks  of chemical
pollutants. Not only are accurate estimates needed to predict
realistic dietary exposures to humans and piscivorous wildlife
but such estimates are also needed to assess more accurately
potential  ecological risks to  fish  assemblages  themselves.
Although exposure-referenced lexicological benchmarks such as
the LC50 and the EC50 have been widely used to make hazard
assessments, most deleterious effects of chemical pollutants are
caused by the internal accumulation of those compounds, rather
than their environmental  concentrations  per se. Numerous
authors (Neely 1984; Friant and Henry  1985; McCarty et  al.
1985;McCarty 1986; ConnellandMarkwell 1992; McCarty and

-------
Mackay 1993; Verhaar et al. 1995; van Loon et al. 1997) have
discussed the need  to  consider chemical bioaccumulation
explicitly when assessing expected ecological consequences of
chemical pollutants in aquatic and marine ecosystems. Residue-
based toxicity studies confirm this supposition (Opperhuizen and
Schrap 1988;vanHoogenand Opperhuizen 1988;Donkinetal.
1989; Tas et al. 1991; van Wezel et al.  1995;  Driscoll and
Landrum 1997).

Although  the  concentrations  of  moderately  hydrophobic
chemicals in fish often can be predicted accurately by assuming
equilibrium partitioning of the chemicals between  the fish's
organic constituents and the aqueous environment, this approach
frequently fails to predict observed concentrations of extremely
hydrophobic chemicals and metals that are often the  chemicals
of greatest concern.  Observed deviations  can  be  in either
direction, with calculated contamination  levels being both
considerably above and below those predicted by equilibrium
partitioning. Several factors can be identified to  explain these
discrepancies.

Lower than expected contamination levels can result when the
length  of exposure  is  insufficient  to  allow  chemicals to
equilibrate. Because bioconcentration and bioaccumulation are
generally treated as linear, first order kinetic processes, the time
needed for chemicals to equilibrate  between fish  and their
exposure media is an increasing function of the elimination half
lives of those chemicals in fish. For example, the time required
for chemicals to achieve 95% of their equilibrium concentrations
is approximately 4.3 times their elimination half lives. Because
the elimination half lives of chemicals generally increase as their
hydrophobicities increase, the time needed for  chemicals to
reach equilibrium concentrations in fish  also increases as a
function  of  chemical  hydrophobicity.  Consequently,   for
extremely hydrophobic  chemicals such  as polychlorinated
biphenyls (PCBs) and dioxins that have elimination half lives
ranging from months to over a year, the time to equilibrium can
be on the order of years. If the species of concern is relatively
short lived, the time  needed for equilibrium can exceed their
expected life  span. Even when there is  sufficient time  for
equilibration, whole body concentrations of fish can be much
lower than that expected from thermodynamic partitioning due
to  physical dilution of the chemical that accompanies body
growth or to the biotransformation and metabolism of the parent
compound.

One of two possible assumptions are implicitly made whenever
equilibrium-based  estimators are used.  The first of these
assumptions is that only the selected reference route of exposure
is significant in determining the total chemical accumulation in
fish. The alternative to this assumption is that there are actually
multiple routes of exposure which are all covariant with the
chosen reference pathway in a fixed and constant manner. In the
case of bioconcentration factors (BCFs), the implicit assumption
is that virtually all of the fish's accumulated body burden is
exchanged directly with the water across  the  fish's  gills or
possibly  across its skin. Although direct aqueous uptake  is
certainly the most significant route of exchange for moderately
hydrophobic chemicals, dietary uptake accounts for most of a
fish's body burdens for extremely hydrophobic chemicals. This
shift in the relative significance of the direct aqueous versus the
dietary pathway is determined by the relative rates of exposure
via these media and by a fundamental difference in the nature of
chemical exchange from food and water. Consider, for example,
the relative absolute exposures to a fish via food and water. The
fish's direct aqueous exposure, AE //g/day, is the product of its
ventilation volume,  Q mL/day, and the chemical's aqueous
concentration, Cw/j.g/mL. Similarly, the fish's dietary exposure,
DE //g/day, is the product of its feeding rate, F g/day, and the
chemical's concentration in the fish's prey, Cp /wg/g. Assuming
that the fish feeds only on one type  of prey that has equilibrated
with the water, one can calculate when the fish's aqueous and
dietary exposures are equal using the equations
                     AE = DE
                   QCv=FCp
                   Q I F = BCF
(1-1)
Using data from Stewart et al. (1983) and Erickson and McKim
(1990) the ventilation-to-feeding ratio for a 1 kg trout would be
on the order of 104 3 mL/g. Assuming the quantitative  structure
activity relationship (QSAR) forthe trout's prey is BCF= 0.048
^(Mackay 1982), one would conclude that food is the trout's
predominant route of exposure for any chemical whose octanol/
water partition coefficient is greater than 105 6. For extremely
hydrophobic chemicals, not only will fish be more exposed via
food but they probably will assimilate chemicals from food more
effectively than from the water. Although chemical exchange
from both food and water occur by passive diffusion, uptake
from food, unlike direct uptake from water, does not necessarily
relax the diffusion  gradient into the fish. This fundamental
difference results from the digestion and assimilation of food
that can actually cause the chemical concentrations of the fish's
gut contents to increase (Connolly and Pedersen 1988;  Gobas et
al.  1988).  Predicting  residue levels  for chemicals whose
principal route of exchange is dietary is further  complicated
since most fish species demonstrate well defined size dependent,
taxonomic,  and temporal  trends  regarding  the prey they
consume. Consequently, one would not generally expect a single
BAF to be sufficiently accurate for risk assessments for all fish
species or even different sizes of the same species.

Process-based models that  describe the kinetic exchange of
chemicals from food and water and the growth of fish provide
objective and scientifically defensible tools that can overcome

-------
many of the limitations  of  equilibrium-based  predictors  of
bioaccumulation identified above. Although numerous models
have been developed to describe the dynamics of chemical
bioaccumulation in fish, (Norstrom et al. 1976; Thomann 1981,
1989; Jensen et al. 1982; Thomann and Connolly 1984; Gobas
et al.  1988; Barber et al.  1991; Thomann et al. 1992; Gobas
1993; Madenjian et al. 1993), these models differ significantly
with regard to how food web structure and dietary exposures are
represented.

This   report   describes   the   theoretical   framework,
parameterization, and use of a generalized, community-based,
bioaccumulation model  called BASS (Bioaccumulation and
Aquatic System Simulator).  This process-based, Fortran  95
simulation model is designed to predict the growth of individuals
and populations within an age-structured fish community and the
bioaccumulation dynamics of  those  fish when exposed  to
mixtures of metals and  organic  chemicals. The  model  is
formulated such that its parameterization does not rely upon
calibration data sets from specific toxicokinetic and population
field studies but rather upon physical and chemical  properties
that can be estimated using chemical property calculators such
as CLOGP (hUE^/w^^bJobjJc^oi]3/bb_/Brod/clogB4(UiUiin , or
SPARC    (Carreira    et    al.     1994;
                                                 and on
ecological, morphological, and physiological parameters that can
be obtained from  the published literature or computerized
databases.

-------
                                            2. Model Formulation
To  model the chemical bioaccumulation and the growth of
individuals and populations within an  age-structured fish
community, BASS solves the following system of differential
equations for each age class of fish
           dt
                 dB     T     T    ,,
                 —  = J  + J  - M
                 dt     g
               = F-E-R-EX- SDA
                             (2-1)
                dN
                 dt
= - NM - PM
                             (2-3)
where B and Wd denote the chemical body burden (//g/fish) and
dry body weight (g(DW)/fish) of the average individual within
the age class and N denotes the age class's population density
(fish/ha). In Eq.(2-l) Jg and J, denote the net chemical exchange
across a fish'  s gillfrom the water and across its intestine from
food,  respectively,   and  M   denotes  the  chemical's
biotransformation or metabolism. In Eq.(2-2) F, E, R, EX, and
SDA denote the fish' s feeding, egestion, routine respiration,
excretion, and specific  dynamic  action  (i.e., the additional
respiratory expenditure in excess of R required to assimilate
food),  respectively.  Although many  physiologically based
models for fish growth are formulated in terms of energy content
and fluxes  (e.g.,  kcal/fish  and  kcal/d),  formulating  a
physiologically based growth model in terms of dry weight is
fundamentally identical to the former since the energy densities
of fish depend on their dry weight (Kushlan et al. 1986; Hartman
and Brandt 1995b). Finally, in Eq.(2-3) M/and PM denote the
age class's non-predatory and predatory mortality, respectively.
Although migration can be a significant process in determining
population sizes, this process  is presently ignored in BASS.
Though it may not be immediately apparent from the above
notation, these equations are tightly coupled to one another. For
example, the realized feeding of fish depends on the availability
(i.e., density andbiomass) of suitable prey. The fish's predatory
mortality in turn is determined by the individual feeding levels
and population densities of its predators. Finally, the fish's
dietary exposure is determined by its rate of feeding and the
levels of chemical contamination in its prey.

The following sections describe how each mass flux in the above
system of equations is formulated in BASS. Table 1 summarizes
the definitions of all  the  variables  used to develop these
equations.  Because the system  of units used  to formulate
chemical exchanges is essentially the CGS-system (centimeter,
gram, second) and the system of units used to formulate a fish'  s
growth is the CGD-system (centimeter, gram, day), some units
conversion is necessary to make the coupled system of equations
dimensionally consistent.  The reader should also note that
whereas the  growth of fish is described in terms of dry weight,
modeling the bioaccumulation of chemicals in fish requires
knowledge of their live weights since the folio wing formulations
of the bioaccumulation process will be developed in terms of
diffusive exchange between aqueous phases.
                             (2-2)      2.1. Modeling Internal Distribution of Chemicals
Chemical exchanges across gills of fish and from their food are
generally considered to occur by passive diffusion of chemicals
between a fish's internal aqueous phase and its external aqueous
environment whether it be the surrounding ambient water or the
aqueous phases of the fish's intestinal contents. Consequently,
to model these exchanges one must first consider how chemicals
distribute with the bodies offish. If individual fish are conceptu-
alized as a three-phase solvent consisting of water, lipid, and
non-lipid  organic matter, then their whole  body  chemical
concentration can be expressed as
                                              C, =  —  = P C  + P,C, + P  C
                                               f    TTT     a  a     II    o  o
                                                        =  P  +  P, —L+P  -Ji   C
                                                                                         (2-4)
                                        where Wfis the fish's live weight (g(FW)); Pa, Ph and P0 are the
                                        fractions of the whole fish that are water, lipid, and non-lipid
                                        organic  material,  respectively; and  Ca,  C,,  and C0  are the
                                        chemical'  s concentrations  in those  phases.  Because the
                                        depuration rates of chemicals from different fish tissues often do
                                        not differ  significantly (Grzenda et al. 1970; van Veld et al.
                                        1984; Branson et al. 1985; Norheim and Roald 1985; Kleeman
                                        etal. 1986a, 1986b), internal equilibration between these three
                                        phases can be assumed to be  rapid in comparison to external
                                        exchanges. For organic chemicals  this assumption means that
                                        Eq.(2-4) simplifies to
                                                    Cf = (P.
                                                  (2-5)
                                        where K, and K0 are partition coefficients between lipid and
                                        water and between organic carbon and water, respectively.

                                        For metals, however, Eq.(2-4) is in theory more complicated.
                                        Although metals do partition into lipids (Simkiss 1983), their
                                        accumulation within most  other organic media occurs  by
                                        complexation  reactions   with  specific  binding  sites.
                                        Consequently, for metals it would seem that the term P0CJCa in
                                        Eq.(2-4) should be formulated as a function of an appropriate

-------
stability  coefficient  and the  availability of binding  sites.
Appendix A. summarizes an equilibrium complexation model
that was initially formulated for  BASS. Despite its  apparent
correctness, this  algorithm  greatly overestimated metal (in
particular mercury) bioaccumulation in fish. Although this
overestimation can be attributed to several factors,  the most
likely explanation for the algorithm's unsatisfactory performance
is that kinetics limits the complexation of metal in fish. Because
kinetic modeling was considered to be inappropriate to the time
scales  of most  of the other  major  processes  represented
elsewhere in BASS, a much simpler algorithm was adopted.

Because  many fate and transport  models (e.g., EXAMS and
WASP)   have   successfully  used  operationally  defined
distribution coefficients Kd to model the accumulation  of metals
in organic media, the same approach was adopted for BASS.
Thus, for a metal
            cf =
  p.
            PK, C.
(2-6)
where K, is again an appropriate partition coefficients between
lipid and water  and Kd is  an appropriate  metal specific
distribution coefficient. Although this equation appears identical
to Eq.(2-5) for organic contaminants, the relative values of Kd
and K0 in relation to K, can be remarkably different. See Section
3.1.

Because Cw equals Ca at equilibrium, it follows from Eq.(2-4)
that the thermodynamic bioconcentration factor (Kf = C/CW at
equilibrium) for a chemical in fish would be
   Kf =
           P
                         o^d
                     for organics

                     for metalics
                               (2-7)
2.2. Modeling Exchange from Water

Because chemical exchange across the gills of fish occurs by
simple diffusion, such exchanges can be modeled by Pick'  s first
law of diffusion as follows
               J
= S  k
   g  g
- C,
                                  (2-8)
where Sg is the fish'  s total gill area (en), kg is the chemical'  s
conductance (cm/s) across the gills from the interlamellar water,
and  Cw  is  the  chemical'  s  concentrations /4g/mL) in  the
environmental water.  See Yalkowsky et al. (1973), Mackay
(1982), Mackay and Hughes (1984), Gobas et al. (1986), Gobas
and Mackay (1987), and Erickson and McKim (1990). When
Eqs.(2-4) and (2-7) are substituted into this equation, one then
obtains
                Cf
J  = Ski C--i
                                                 (2-9)
                                             Although according to Pick' s first law the conductanc&g of a
                                             chemical across a fish's gill could be specified as a ratio of the
                                             chemical's diffusivity to the thickness of an associated boundary
                                             layer, implementation of this definition can be  problematic
                                             because the thickness of the boundary layer varies along the
                                             length of the gill's secondary lamellae and is a function of the
                                             gill'  s ventilation velocity. To circumvent this problem, a fish's
                                             net chemical exchange rate, Sg kg, can be objectively estimated
                                             by reformulating the gill' s net chemical exchange as
                                                             J  = Q(C  - CR)
                                                              Z   ^ ^  W     B'
                                                                                          (2-10)
                                             where Q is the fish' s ventilation volume (cnis) and CB is the
                                             bulk concentration of the chemical in the water expired from the
                                             gills. When Eqs. (2-8) and (2-10) are equated, it follows that
                                                           S k  = O
                                                                                      c,., - c.
                                                                                          (2-11)
                                             Despite its appearance, the right hand side of this equation can
                                             be readily quantified. In particular, the ventilation volume offish
                                             can be estimated by
                                                               Q =
                                                                                          (2-12)
           where O2 is the fish's rate of oxygen consumption (,ug/s), am is
           the fish' s oxygen assimilation efficiency an^Cw02 is the water's
           dissolved oxygen concentration (/^g/mL). And if one now makes
           certain assumptions concerning the geometry of the interlamellar
           spaces and the nature of mass transport between the secondary
           lamellae, the normalized bulk concentration of the exhalant gill
           water (Cw-CB)/(Cw-Ca)can also be formulated.

           Because the gill's secondary lamellae form flat channels having
           very high aspect ratios (i.e., mean lamellar height / interlamellar
           distance), the lamellae can be considered as parallel plates and
           the flow of water between them can be treated as Poiseuille slit
           flow (Hills and Hughes 1970; Stevens and Lightfoot 1986).
           Under this   assumption,  an  expression  for a  chemical'  s
           concentration in the bulk exhalant gill water can be obtained
           using the solutions of the partial differential equation (PDE) that
           describes steady-state convective mass transportbetweenparallel
           plates, i.e.,
                                                                      ^-D—,          (2-13)
                                                                    dy
                                                                                dx
                                             where V (cm/s) is the gill's mean interlamellar flow velocity, D
                                             (cnf/s) is the chemical's aqueous diffusivity, and x andy are the
                                             lateral and longitudinal coordinates of the channel along which
                                             diffusion and convection occurs, respectively. In this equation
                                             C = C(x, y) denotes the chemical's interlamellar concentration at

-------
the distances x from the surface of the lamellae andy along its
length. The surfaces of adjacent lamellae are located at x = ±h
where h is the hydraulic radius of the lamellar channel which
equals one half of the interlamellar distance d (cm). The midline
between adjacent lamellae is therefore denoted by x=0. The
mean interlamellar flow velocity, V (cm/s), can be formulated as
the ratio of the fish's ventilation volume to the cross sectional
pore area, Xg (cm2), of its gills. Because this pore area is related
to the gill's lamellar surface area by
                   x  -s'd
                   x'~~r
                                      (2-14)
where d (cm) is the mean interlamellar distance and / (cm) is the
mean lamellar length (Hills and Hughes 1970), a fish's mean
interlamellar flow velocity is given by
                                               (2-15)
                         S  d
To  solve the above PDE two boundary conditions must be
specified. Because adjacent lamellae presumably exchange the
chemical equally well, the solutions should be symmetrical about
the channel'  s midline. To insure this characteristic, the boundary
condition
                   3C
                   dx
                                      (2-16)
is  assumed. The second necessary boundary condition must
describe how chemical exchange across the secondary lamellae
actually occurs.  Assuming steady state diffusion  from the
interlamellar water to the fish's aqueous blood, this boundary
condition can be formulated as

            f      = -*- (CM - Ca)          (2.17)
D-
where  km is the permeability of the gill membrane  (cm/s).
Although this boundary condition could be used as is (Barber et
al. 1991), it can also be modified to address potential perfusion
limitation of gill uptake. To accomplish this task a formulation
patterned after Erickson and McKim (1990) can be used. In
particular, consider the following reformulation
    DdC
       dx
    = -km(C(h,y)-Ca(y))
                                               (2-18)
where Ca(y) denotes the aqueous phase concentration of the
chemical at point y along the length of a secondary lamella, Ca(l)
= Ca denotes the chemical'  s concentration in the afferent lamellar
                                                  blood, U(y, I) is the chemical's accumulated rate of uptake C^g/s)
                                                  along the lamellar segment [y, /], and qp is the lamellar perfusion
                                                  rate(cnrVs). If both sides of the lamella uptakes chemical, then
                                                  U(y, 1) can be formulated as
                                                                                    dzdy
                                                                                      dx
                                                                                                  (2-19)
                                                                                            dy
                                                  where z denotes the height (cm) of the secondary lamella. Using
                                                  this expression, the boundary condition (2-18) can now be
                                                  written as
                                                   DdC
                                                      dx
                              2zD
= -tlc(M-cfl-^f'^
                                                                                                  dx
                                                                                                        dy
                                             fy  (2-20)
                                                  Once the solution of Eq.(2-13)forthese boundary conditions has
                                                  been obtained, the chemical's bulk concentration in the exhalant
                                                  gill water can be evaluated using the weighted average
                                                                    fh C(x,l)(l -x2)dx
                                                             "              —V—           (2-21)
                                                                       f*
                                                                      Jo
that scales each concentration profile C(x,  /) by its relative
velocity.

A canonical  solution to  Eq.(2-13)  can  be obtained by
nondimensioning C(x, y), x, and>- as follows
                        C - C.
                  @  =
                                                                               Y =
                       cw-ca

                        ' H
                         y D
                                                                                    Vh
                                       (2-22)

                                       (2-23)

                                       (2-24)
                                                  where h is the hydraulic radius of the lamellar channel (i.e., one-
                                                  half the interlamellar distance). When this is done, the chemical's
                                                  dimensionless bulk concentration is given by
                                                                        f1 @(X,NGz)(l -X2)dx
                                                                                                   (2-25)
                                                                     C,., - C
                                                                             f1  (l -X2)dX
                                                                            Jo
where N& = (ID) / (Vh2) is the lamellae's dimensionless length
or Graetz  number. Two  important points concerning this
expression can now be made. Firstly, one can easily verify that
                                                                           1
                                                                                     c,., - c_
                                                  and therefore Eq. (2-11) can be rewritten as
                                                                                                           (2-26)
                                                                                                           (2-27)

-------
Secondly, analytical expressions for ®B are readily available
(Brown 1960; Grimsrud and Babb 1966; Colton et al.  1971;
Walker  and  Davies  1974).   In  particular,  a  chemical's
dimensionless bulk concentration can be evaluated by
                                                (2-28)
where the coefficients Bm and exponents Xm are known functions
of the lamellae's dimensionless  conductance or  Sherwood
number

                   jV   =  m                      (2-29^
                     sh    D                     (2 ^]
and the fish's ventilation/perfusion volume ratio. See Appendix
B. Although this infinite  series  solution does  not have  a
convenient convergence formula, for Sherwood numbers and
ventilation/perfusion ratios that are typical offish gills, only the
first two terms of the series are needed to evaluate ®B with less
than 1% error (also see Barber et al. 1991).

2.3. Modeling Exchange from Food

Chemical uptake from  food has usually been  modeled by
assuming that a fish can assimilate a constant fraction of the
chemical it ingests, i.e.,
                  Jt  = *c CP Ff                  (2-30)
where 
-------
however,  is  not without  problems  since the  fish's  food
assimilation efficiency can vary significantly with feeding rate,
food quality,  temperature and other factors. Nevertheless, the
results of studies by Lieb et al. (1974), Gruger et al. (1975), and
Opperhuizen  and  Schrap  (1988) which are analyzed  and
discussed in Barber et al. (1991) corroborate these predicted
tends. Recent studies by Dori et al. (2000) who used in situ
preparations  of  channel  catfish  intestines,  have  clearly
established that preexposures  to 3,4,3',4'-tetrachlorobiphenyl
does indeed decrease intestinal uptake rates.

Muiretal. (1992), Dabrowska et al. (1996), and Fisketal.( 1998)
have investigated chemical assimilation efficiencies of rainbow
trout and channel catfish using a model proposed by Bruggeman
etal. (1981), i.e.,
               dCf
               ~dT
               = a f Cp - k2 Cf
               = afC
                    1 -exp(-&2 f)
                         E
(2-34)
(2-35)
where  a is a constant assimilation efficiency, / is the fish's
specific rate of feeding (g/g/d), and k2 is the chemical's apparent
elimination rate which necessarily must include actual excretion,
biotransformation, and growth dilution. Eq.(2-35), however, is
only the solution to Eq.(2-34) when  C,(0) =0.  The general
solution to  Eq.(2-34) is actually
                 -exp(-&2
                           C,(0) exp(-£2  /)
          k7
                                                 (2-36)
                                     exp(-&2 f)
Acknowledging this fact is of paramount importance to interpret
the results reported by Muir et al.  (1992), Dabrowska et al.
(1996), or Fisk  et al. (1998) correctly in light of the fecal
partitioning model proposed herein.  When this solution  is
redifferentiated, one observes that
dC,                afC
—T =  '  C(0) ~
 dt
                 /
                                            0    (2-37)
Now let T denote the length of a bioaccumulation experiment in
which Cj(0)=0 and /and  Cp are constant, i.e., such as those
studies cited above. Also let a and k2 denote the assimilation
efficiency and apparent depuration rate that were estimated for
this experiment. When the experiment is half over, the rate of
change  in  the  fish's whole body concentration would be
calculated by Eq.(2-37) to be
         dC
          dt
                   =  afCp exp(-£2 772)
                                            (2-38)
                                                        If one now elects to arbitrary restart time, the bioaccumulation
                                                        dynamics for the  second half of the  experiment would be
                                                        described by
                                                                  afC
                                                             c  -     p
                                                              f       ~
                                         afCp

                                          1
                                    exp(-£2T)    (2-39)
                                                        where a  and  k2 denote  updated estimates for the fish's
                                                        assimilation  efficiency  and apparent  depuration rate for
                                                        0 < T < 772. This equation can also be differentiated to yield
                                                              dC,
                                                              di
                                     afC }
                            Cf(T/2) - ——p-  k2 exp(-£2 T)
                                       £
                                                        which can be evaluated at T = 0 to yield
          dC,
          di
= &fCp  -k2Cf(TI2)
                                                 (2-40)
(2-41)
For logical as well as mathematically consistency this derivative
should equal the derivative given by Eq.(2-38), i.e.,

    &fCp-k2 C/772)  = a f Cp exp(-£2 T/2)    (2-42)

Solving for cc then yields

                           k2 Cf(T/2)
                                                              afCp exp(-£2 772)
                                                                                         Cf(TI2)

                                                                                                        ,(2-43)
                                                           = a   exp(-&2772)  +  — (l  - exp(-A:2 772))
            This equation shows that unless k2=k2, chemical assimilation
            efficiencies estimated for different times and initial whole body
            concentration will be different.  Phrased  another  way, this
            equation implies that the fish's ability to excrete, biodilute, and
            biotransform chemicals, as measured by k2 and k2 , contributes
            to the determination of the fish's realized chemical assimilation
            efficiencies. Specific growth rates and chemical excretion rates
            for fish, however, are generally related to the fish's body size as
            allometric power functions, i.e.,
                                                        where in general p2<0(Barber et al.  1988; Sijm et al. 1993,
                                                        1995;  Sijm and van  der Linde  1995).  Therefore,  if  any

-------
significant growth occurs during the experiment, which is often
the case, one would not expect that k2 = k2 and consequently one
would not expect a = a. In point of fact one would generally
expect a > a. Importantly, this simple analysis is corroborated
by findings of  Ram and  Gillet (1993) who  showed that
assimilation efficiencies for a variety of organochlorines by
oligochaetes decreased as chemical exposures progressed.

In terms of application the above fecal partitioning model is best
suited to  circumstances where its equilibrium assumptions are
best met such as the case herein where the object is to predict the
dietary exchange of average individual of an explicit or implicit
population. A more kinetically based approach may be needed,
however, when trying to describe the toxicokinetic of individual
fish.  See  for example Nichols et al. (1998).

2.4.  Modeling Chemical Biotransformation

BASS  assumes  that the metabolism of xenobiotic chemicals in
fish is a simple first order reaction of the chemical's aqueous
phase concentration, i.e.,
                M = -pca(par>
                                                (2-45)
where Mis the total amount of chemical metabolized (ug / ml),
p is the fish's biotransformation rate (I/day), and (Pa W) is the
volume of the volume of the fish's aqueous phase. If Eqs. (2-9)
and (2-45) are used to  described  the bioconcentration of a
chemical in fish during a water only exposure without growth,
then a fish's whole body concentration would be modeled as
         dCf _  i dBf
         dt     W dt
                S k
                 g g
                 W
                                                (2-46)
                                     Kf
             — /V W    ^A-  ^ /V J \^f-

where ku, ke, and km are the fish's uptake rate, elimination rate,
and  biotransformation rate,  respectively,  which are  often
reported in the literature. In terms of quantitative structure
activity relationships (QSARs), one should note that this model
predicts that the whole body biotransformation rate km should be
inversely  proportional   to  the   fish's   thermodynamic
bioconcentration factor Kf which in turn is proportional to  the
chemical's Kow.  This relationship, however,  will  also  be
influenced by any Q S AR dependencies which the fish' s aqueous
phase biotransformation rate p might have. See de Wolf et al.
(1992) and de Bruijn et al. (1993).

2.5.    Modeling   Temperature   Effects    on
Physiological Rates

Because  temperature  effects  a fish's feeding,  assimilation,
respiration,  and  egestion, a general  discussion  of how
temperature  modulates these  processes is in order before
describing how BASS actually models fish growth. Although the
temperature dependence of physiological processes are often
described using an exponential response equation, e.g.,
                 *,  =k0ef^-T°>                 (2-47)
where k0  and k1 are the process's reaction rates at temperatures
T0 and T,, respectively, such descriptions are generally valid only
within a  range of the  organism's thermal tolerances. In most
cases, the process's reaction rate increases exponentially with
increasing temperature up to  a temperature T1 after which it
decreases. Moreover, in most cases the temperature at which a
process's rate is maximal is very close to the organism's upper
thermal limit. To address this  problem, Thornton and Lessem
(1978) developed  a  logistic  multiplier   to  describe the
temperature  dependence of a wide variety of physiological
processes. Although this algorithm has been used  successfully
in a  variety of  fish bioenergetic models,  BASS  uses  an
exponential-type formulation  that is  assumed  to response
hyperbolically to increasing  temperature.  Importantly, such
algorithms can be easily parameterized.

Let P denote the rate of a physiological process and T1 denote
the temperature at which this  rate is maximal. If this process
generally exhibits an exponential response  to  temperature
changes well below Th then
                 P  = P0e*(T~T^                 (2-48)

                   —  = Jp                    (2-49}
                     dT                          ^ ^)
where P0 is the process's rate at an appropriate lower-end
reference temperature  T0. To incorporate the adverse effects of
high temperatures on this process, the right hand side of Eq.(2-
49) can be multiplied by a hyperbolic temperature term that
approaches unity as temperature decreases below Th equals zero
at Th and becomes  increasingly  negative as temperatures
approach the fish's upper thermal  tolerance  limit TL  =  T2.
Modifying Eq.(2-49) in this fashion subsequently yields
                                                            whose solution is
                                                                                                              (2-50)
                                                                                                              (2-51)
                                                            Figure 1 displays the predicted temperature response of the
                                                            maximum feeding of a 50 g brown trout (Salmo truttd) based on
                                                            data reported by Elliott (1976b, Tables 2 and 9). For this figure

-------
it is assumed that T0 = (3.8 + 6.6)12, 1\ = 17.8, and T2=25. The
parameters P0 = 340 and y = 0.50 were then calibrated using the
results of a non-linear least squares analysis as a starting point.
For other applications of this model see Lassiter and Kearns
(1974) and Swartzman and Bentley (1979). Note that when T, =
T2, the Eq.(2-51) reduces to Eq.(2-48).

2.6. Modeling Growth of Fish

Although the  preceding  formulations  of the  processes that
determine the bioaccumulation of chemicals in fish depend on a
fish's live weight, BASS does not directly simulate the live weight
of fish. Instead, it simulates the  dry weight of fish as the mass
balance of feeding, egestion, respiration, and excretion and then
calculates the fish's associated wet weight using the following
relationships
                w =  w  +  w
                       a      L
                  =  w  +  w,
d
                   PI =
                P=l-P-P,
                    (2-52)
                    (2-53)

                    (2-54)

                    (2-55)
where Wa, Wd, W,, and W0 denotes the fish's aqueous, dry, lipid,
and non-lipid organic weights, respectively. Whereas Eqs.(2-52)
and (2-55) are simply assertions of mass conservation, Eqs. (2-
53) and (2-54) are purely statistical in nature. Although Eq. (2-
53) is assumed because simple power functions of this form
generally describe a wide variety of morphometric relationships
for most organisms, the appropriateness of Eq. (2-54) is based
on  the  results  of numerous field  and  laboratory studies
(Eschmeyer and Phillips 1965; Brett etal. 1969;  Groves 1970;
Elliott 1976a; Staples and Nomura 1976; Craig 1977;  Shubina
and Rychagova 1981; Beamish and Legrow 1983; Weatherley
and Gill 1983 ;Flath and Diana 1985; Lowe etal. 1985;Kunisaki
et al. 1985; Morishita et al. 1987). These equations  yield an
expression for  a fish's live weigh  that is a monotonically
increasing but non-linear function of the fish's dry weight.

BASS calculates a fish's realized feeding by first estimating its
maximum ad libitum consumption  and  then  adjusting this
potential by the availability of appropriate prey as described in
the next section. Because a wide variety of models and methods
have been used to describe maximum feeding of fish, BASS is
coded to allow a user the option of using any one of four
different models to  simulate  the feeding of any particular
age/size class of fish. The first formulation that can be used is a
temperature-dependent power function
       max    Cl
                                                                                  (2-56)
                                where the temperatures T0, Tlt and T2 are specific to the fish's
                                feeding. A  commonly used alternative to  this model  is the
                                process-based Rashevsky-Holling model that is defined by the
                                equations
                                                 max   T \ max     /
                dl
               — = C
                dt
where  (j) is  the fish's ad libitum feeding  rate (day"1) that is
generally  a  temperature-dependent  power function of body
weight, Imai is the maximum amount of food (g(DW)) that the
fish's stomach/intestine can hold, /is the actual amount of food
(g(DW)) present in the intestine, and A and E again are the fish's
assimilation (g(ow)/day) and egestion (g(ow)/day) , respectively
(Rashevsky  1959;  Holling 1966). The feeding rate (f) can be
estimated using the following equations
            M(t) = J'<|>(/max-M(T))rfT            (2-58)
                                                                             dt
                                                  (2-59)

                                                  (2-60)
                                where M(t) denotes the total amount of food consumed during
                                the interval (0,/J (also see Dunbrack 1988). Although given a
                                fish's gut capacity Imax, satiation meal size Msat, and time tsat
                                required to ingest Msat one can readily calculate (f), one can also
                                simply assume thatM^, = 0.95  x Imai in which case
                                                         ln(0.05)
                                                                                  (2-61)
                                For planktivores BASS can also estimate a fish's maximum
                                ingestion using the clearance volume model
                                                   C
                                      Qd = 9i Wq* e-
                                                                                  (2-62)
                                where T is the plankton standing stock (g(DW)/L), Qcl is the
                                planktivore's clearance volume (L/day), and the temperatures T0,
                                T{, and T2 are specific to the fish's filtering rate. The fourth and
                                final option is based on knowing the fish's proj ected growth and
                                routine respiratory demands. In particular, because assimilation,
                                egestion,  specific  dynamic  action, and excretion can  be
                                calculated as linear functions of feeding and routine respiration
                                as discussed below,  it is then a straightforward  matter to
                                calculate a fish's expected ingestion given its projected growth
                                and respiration. When a user elects this feeding option, BASS
                                assumes that the fish's specific growth rate y (day"1) is given by
                                                          10

-------
                                I  T — T \  3  2   l
 Y = r-i IE = gi w* e«
-------
ASSUMPTION 1. The competitive abilities and efficiencies of
benthivores and piscivores are positively correlated with their
body sizes (Garman and Nielsen 1982; East and Magnan 1991).
Two general empirical trends support this assumption. The first
of these is the trend for the reactive distances, swimming speeds,
and territory sizes of fish to be positively correlated with their
body size (Minor and Grossman 1978; Breck and Gitter 1983;
Wanzenbock and Schiemer 1989;  Grant and  Kramer  1990;
Miller et al. 1992; Keeley and Grant 1995; Minns 1995). Given
two differently sized predators of the same potential prey, these
trends would suggest that the larger predator is more likely to
encounter that prey than is the smaller. Having encountered the
prey, the trend for prey handling times to be inversely correlated
with body  size (Werner 1974; Miller et al. 1992) would also
suggest that the larger predator could dispatch the prey and
resume its foraging more quickly than the smaller predator.

ASSUMPTION  2. Unlike benthivores  and  piscivores,  the
competitive abilities and  efficiencies  of  planktivores  are
inversely related to  their body size due  to their  relative
morphologies  (Lammens et. al. 1985; Johnson and Vinyard
1987; Wu and  Culver 1992; Persson and  Hansson 1999).
Consequently, "large" planktivores only  have access to  the
leftovers of "small" planktivores.

BASS calculates  the  relative frequencies  {...,dt,...}  of  the
different prey  consumed by a cohort using dietary electivities,
i.e.,
                                                 (2-71)
where/ is the relative availability of the i-th prey with respect to
all other prey consumed by the cohort. These electivities are
calculated dynamically by BASS using dietary data specified by
the user and the relative availabilities of the cohort's  prey
currently predicted by BASS. As described in the discussion of
BASS' sdiet command  (see page  38), BASS allows a user to
specify a fish' s diet as either a set of fixed dietary frequencies
{..., dj,...}, a set of electivities {...,e.,...}, or a combination of
fixed frequencies and electivities {..., d.,..., e},...}. In order to
calculate the  cohort's realized dietary composition, BASS first
converts all fixed dietary frequencies specified by the user into
their equivalent electivities  using Eq.  (2-71) and the current
relative availabilities  {...,fj,...} of all  potential prey. These
electivities are then combined with any user specified electivities
to form a set of unadjusted electivities {...,et,...} which in
general must then be converted into a consistent set of realized
electivities {..., et,...}. Using these realized electivities, BASS
finally calculates the cohort's realized dietary frequencies using
                        1
             The  important  step in this computational  process is the
             conversion of the unadjusted electivities {...,e.,...} intoasetof
             realized electivities {...,e.,...}. Although this  conversion  is
             sometimes unnecessary, it is generally needed to  insure that the
             sum of the dietary frequencies {..., df,...} calculated by Eq.(2-
             72)  equals  1.   One  can verify that  the  condition  that
             guarantees S d.  = 1 is
                              E
                                   1 -
                              = 1
                                                 (2-73)
             See Appendix C. When this condition is not satisfied for a set of
             electivities {...,et,...} and relative prey availabilities {...,fj,...},
             BASS  transforms  the  given  electivities  using  a  linear
             transformation that maps e. = -1 into et = -l and max(..., e.,...)
             into an e. < 1. The general form of this transformation is
                            ei  = a (et + 1) -  1
                                                 (2-74)
             where  0
-------
are more efficient piscivores (see assumption 1 above). If more
than one age class of species /' can be consumed by the cohort,
the relative frequencies of these age classes su in the cohort's
diet are calculated using the cohort's prey size distribution. For
example, let Ltl and La denote the body lengths of two age
classes of species /' that are prey for the cohort. If Pv denotes the
probabilistic density
                 1
                      exr
       - Lpreyf
               2 TZ O
                        (2-77)
the relative frequencies of these two age classes in the cohort's
diet   are   calculated  to  be  Sj^d^Pjj/iPjj+P^))   and
si2 = di(Pi2/(Pil+Pi2)). If only one age  class of a species is
vulnerable to the cohort, then sfj = di.

If during the calculation  of  the dietary  frequencies of  a
piscivorous cohort BASS predicts that the cohort's available prey
is insufficient to satisfy its desired level  of feeding, BASS
reassigns the cohort's unadjusted electivities  {...,ej*,...} in a
manner to  simulate prey switching.  These reassignments as
based on the following assumption:

AS SUMPTION 3. Whenforage fish become limiting, piscivores
switch to benthic macroinvertebrates or incidental terrestrial
insects as alternative prey. However, piscivores that must switch
to benthos or that routinely consume benthos in addition to fish,
are less efficient benthivores  than are  obligate benthivores
(Hanson and Leggett 1986; Lacasse andMagnan 1992; Bergman
and Greenberg 1994).  Consequently, only the leftovers of non-
piscivorous  benthivores  are  available  to  benthic  feeding
piscivores. If such resources are still insufficient to satisfy the
piscivores' metabolic demands, piscivores are assumed to then
switch to planktivory (Werner and Gilliam 1984; Magnan 1988;
Bergmann and Greenberg 1994). In this  case, piscivores have
access only to the leftovers of non-piscivorous planktivores.

Using this assumption, BASS first assigns  the cohort's electivity
for benthos to 0 regardless of its previous value. BASS also
reassigns any other electivity which does not equal -1, to 0.

After BASS has calculated a cohort's dietary composition, it then
assigns the realized feeding rate of cohort as
         F = max
E
ABj,F^
                                                (2-78)
where  Fmca  is the cohort's  maximum or desired  individual
ingestion, TV is the cohort's population size, and ABj  is the
biomass  of prey j that is available to  that cohort. Using its
predicted dietary compositions and realized feeding rates, BASS
then calculates the predatory mortalities for each cohort and non-
fish biotic resource.
2.8.  Modeling Non  Predatory  Mortalities and
Recruitment

Numerous studies (Damuth 1981; Peters and Raelson 1984;
Juanes 1986;RobinsonandRedford 1986;BoudreauandDickie
1989;GordoaandDuarte 1992; Randall etal. 1995 Dunham and
Vinyard 1997; Steingrimsson and Grant 1999) have shown that
the population densities of vertebrates are generally correlated
with their mean body size. In particular,
                   N  =  a W~b                    (2-79)
where N is the population density (inds/area) of the species or
cohort and Wis the mean body weight of that species or cohort.
Although an interspecific analysis of data for a variety of fish by
Randall et al. (1995) suggests a mean exponent close to unity,
data reported by Boudreau and Dickie (1989) and Gordoa and
Duarte (1992) for individual fish species suggest an average
exponent of approximately 0.75. An expression for a species'
total mortality rate can be obtained by differentiating Eq. (2-79)
as follows

      — =  -b a W   \W   —J  =  -b N y      (2-80)

where y is the species specific growth rate. Based on this
equation, one could therefore conclude that a species' total
mortality rate is simply \a = b y . Readers interested in detailed
discussions   concerning  the  underlying  process-based
interpretation and general applicability  of this  result should
consult Peterson and Wroblewski (1984) and McGurk (1993,
1999). Because BASS assumes that the specific growth rates of
a species are  allometric functions of its body sizes, it follows
that

                   V = bylWy>                 (2-81)

Also  see  Lorenzen  (1996). Because this equation  actually
includes both a species' predatory and non-predatory mortality,
BASS assumes that a species' non-predatory mortality rate is
simply some  fraction 5  of u. In general, this fraction will be
small for forage fish and large for predatory species. During the
course of the simulation BASS calculates the daily non-predatory
mortality each cohort using Eq.(2-81) parameterized with the
cohort's current body weight.

BASS estimates a  species' recruitment by assuming that each
species turns  over a fixed percentage of its potential spawning
biomass into  new young-of-year  (YOY).  This percentage is
referred to as the species' reproductive biomass investment (rbi).
The species' spawningbiomass is defined to be the total biomass
of all cohorts whose body  length is are greater than or equal to
a specified minimum value (tl_rO) marking the species' sexual
maturation. When reproduction is simulated, the body weight of
each sexually mature cohort is decremented by its rbi and the
                                                          13

-------
total number of YOY which are recruited into the population as
a new cohort is  estimated by  simply dividing the species'
spawned biomass by the  species' characteristic YOY body
weight. Although this formulation does not address the myriad
of factors known to influence  population recruitment,  it is
logically consistent with the spawners abundance model for fish
recruitment  (see   Myers   and   Barrowman(1996)  and
Myers(1997)).

2.9. Modeling Toxicological Effects

Narcosis  is  defined  to  be  any  reversible  decrease  in
physiological function that  is  induced by chemical agents.
Because the potency of narcotic  agents was originally found to
be correlated their olive oil / water partition coefficients (Meyer
1899; Overton 1901), it was long believed that the principal
mechanism of narcosis was  the  disruption of the transport
functions of the lipid bilayers of biomembranes (Mullins 1954;
Miller etal. 1973;Haydonetal. 1977; Janoffetal. 1981;Pringle
et al. 1981). More recently, however, it has been acknowledged
that narcotic chemicals also partition into other macromolecular
components besides the lipid bilayers of membranes. It is now
widely  accepted  that  partitioning  of narcotic agents  into
hydrophobic  regions of proteins and enzymes inhibit  their
physiological function either by changing their  conformal
structure or by changing the configuration or availability of their
active sites (Eyring et al 1973; Adey et al. 1976; Middleton and
Smith 1976; Franks and Lieb 1978, 1982, 1984; Richards et al.
1978; Law et al. 1985; Lassiter 1990). In either case, however,
the idea that the presence  of narcotic chemicals increases the
physical dimensions  of various  physiological targets to some
"critical volume" which renders them  inactive is fundamental
(Abernethy et al. 1988). Consequently, narcotic chemicals can
be treated as  generalized physiological toxicants and narcosis
itself can be considered to  represent baseline chemical toxicity
for organisms. Although any particular chemical may act by a
more specific mode of action under acute  or chronic exposure
conditions, all organic chemicals  can be  assumed  to act
minimally as narcotics (Ferguson 1939; McCarty and Mackay
1993).

Studies have shown that for narcotic chemicals  there  is  a
relatively constant chemical activity within exposed organisms
associated with any given level of biological activity (Fergusion
1939;  Brink  and Posternak  1948;  Veith et al.  1983).  This
relationship  holds true not only for  exposures to a single
chemical but also for exposures to chemical mixtures. In the case
of a mixture of chemicals, the sum of the chemical activities for
each component chemical is constant for a given level  of
biological activity. Because narcotic chemicals can be treated as
generalized physiological toxicants as noted above, it should not
be too surprising that the effects of  mixtures  of chemicals
possessing diverse specific modes of action not only often
resemble narcosis but also appear to be additive in terms of their
toxic effects (Barber et al. 1987; McCarty and Mackay 1993).
For example, even though most pesticides possess a specific
mode of action is during acute  exposures, the joint action of
pesticides is often additive and resembles narcosis (Hermanutz
etal. 1985; Matthiessen etal. 1988; Bailey etal. 1997).

BASS simulates acute and chronic mortality assuming that the
chemicals of concern  are an additive  mixture  of narcotics.
Because this assumption is the  least conservative  assumption
that one would make concerning the onset of effects, mortalities
predicted by BASS should signal immediate concern. When the
total chemical activity of a fish's aqueous phase exceeds it's
calculated lethal threshold, BASS assumes that the fish dies and
then eliminates that fish's age class from further consideration.
The total chemical activity of a fish's aqueous phase is simply
the sum of the fish's aqueous phase chemical activity for each
chemical. BASS calculates the aqueous phase chemical activity of
each chemical using the following formulae
                  A   = y M
                   a    * a  a
                           C
                        103 MW
(2-82)
                  ca  =  2.
                        Kf
where Aa is the chemical'  s aqueous activity^ is the chemical' s
aqueous activity coefficient (L/mol) which is the reciprocal of its
sub-cooled liquid solubility,Ma is the chemical's molarity within
the aqueous  phase of the fish,  and MW is the chemical's
molecular weight (g/mol).

BASS estimates the lethal chemical activity threshold for each
species as the geometric mean of the species' LA50,  i.e., the
ambient aqueous chemical activity causes 50% mortality in an
exposed population. These lethal thresholds are calculated using
the above formulae with user-specified LC50'  substituted for Ca.
These calculations are based on two important assumptions. The
first assumption is that the exposure time associated with the
specified LCsg is sufficient to  allow almost complete chemical
equilibration  between  the  fish and  the water.  The second
assumption is that the specified LC50 is the minimum LC50 that
kills  the fish  during the  associated exposure  interval.
Fortunately, most reliable LCsg satisfy these two assumptions.
See Lassiter  and Hallam (1990) for a comprehensive model
based analysis of these issues.

Three points should be mentioned regarding the above approach
to modeling ecotoxicological effects. Firstly, it should be noted
that for narcotic chemicals this approach is analogous to the
                                                          14

-------
toxic unit approach for evaluating the  toxicity of mixtures
(Calamari and  Alabaster  1980;  Konemann  1981a,  1981b;
Hermens and Leeuwangh 1982; Hermens et al. 1984a, 1984b,
1985a, 1985b, 1985c; Broderius andKahl 1985; Dawson 1994;
Peterson 1994). Secondly, the approach is also analogous to the
critical body residue (CBR) and total molar body residue (TBR)
approaches proposed by McCarty and Mackay (1993), Verhaar
et al.  (1995), and  van Loon et al. (1997). Lastly, although
sublethal effects are not presently modeled by BASS, BASS'S
simulation results can be used to indicate when sublethal effects
that are induced by narcotic agents would be expected to occur.
Results reported by Hermens et al (1984a) indicate that for
Daphnia the ratio of the EC50 for reproductive impairment to the
LC50 is generally on the order of 0.15 - 0.30 for chemicals whose
log Kow range from 4  to 8. For individual growth inhibition,
however, the mean EC50 to LC50 ratio for Daphnia in 16 day
chronic exposures was approximately 0.77 (Hermens et at.
1984a, 1985a). Also see Roex et al. (2000).
                                                        15

-------

-8


















?
1
rt
o
IS}
j3
W


















bolism of chemical Owg /s)
+3
8


















llation density (inds/ha)
^
a
^













°\
^
i^
S"
^^
;tz number (dimensionless) =
re
r^











,~.

~^-
•«
^
^
II
wood number (dimensionless
^H
-.
•3
predatory mortality (inds-ha"1
i
S







c/}

i-^
13
o
a
y
s
2

U*l
^
o
 43 T3

                                       § >^
                                   -
§
                        "
H
   3
     bo t
     3.
 r-j -M
 'Tj Cy


 °^
 s ^

 •S a
 a s
 2 =3
  k>


 1^
            ^i
            ~Sf^i
            ,-s ^
       C -B



       II

                   3.
        •i£
fraction of
    1> CH
          C C C

     sccccccs
     ooooooooo
   .3222222222
   1
 c c c c c c
 ^ Q) Q) Q) Q) Q)

 8 8 8 8 8 8
 888888
     re re re re re c^
     o o o o o o


     1> 1> 1> 1> 1> 1>

     000000
^H   H -s
° ^ ° i

llll
g bJ) O 

il^l
g^ugl
O ^ g S

-------
Figure 1. Application of Eq.(2-51) to describe the temperature dependence of the maximum daily consumption of brown trout (Salmo
trutta) based on Elliott (1976b, Tables 2 and 9).
                        5275.00
                        4220.00 -
                    •§  3165.00
                    O,
                    S
                    3
                    C/3
                    C
                    g  2110.00


                    £
                    3


                    *  1055.00
                    S3
                           0.00
                              2.00
                                            6.60
                                                         11.20
                                                                      15.80
                                                                                   20.40
                                                                                                 25.00
                                                             Celsius
                                                          17

-------
                                         3. Model Parameterization
Because reliable application of a model depends not only on the
validity of its formulation but also on its parameterization,
important aspects of parameterizing the above equations are now
discussed.

3.1. Parameterizing Kf

Superficially,   estimation  of   a  fish's  thermodynamic
bioconcentration factor Kfvia Eq. (2-7) appears to require a great
deal of information. This task, however,  is much simpler than
it first appears. For example, given a fish's lipid fraction (see
Eq.(2-53)), it is a straightforward matter to calculate the  fish's
aqueous fraction using Eq. (2-54). Having done so, one can then
immediately calculate the fish's non-lipid organic fraction since
the sum of Pa, P,, and P0 must be unity (i.e., Eq. (2-55)).

For an organic chemical the partition coefficients Kfand K0 can
be  estimated  using  the  chemical's  octanol/water  partition
coefficient Km. Although triglycerides are the principal storage
lipid of fish and it would seem reasonable to estimate K, using
a triglyceride/water partition coefficient, BASS assumes that K,
identically equals K^. To estimate K0 BASS assumes that a fish's
non-lipid organic matter is equivalent to organic carbon and uses
Karickhoffs (1981) regression between organic carbon/water
partition coefficients (Koc), and Km to estimate this parameter.
Specifically,
               Ko  =Koc  = OAUKow                (3_l)

For   metals   or   metallo-organic   compounds   such   as
methylmercury the chemical's lipid partition coefficient K, can
again be assumed to equal its octanol/water partition coefficient
K^. A metal's distribution coefficient into non-lipid organic
matter, however, cannot be estimated using the Koc relationship
given above. For example, whereas the Kow of methylmercury at
physiological pH's is on the order of 0.4  (Major et al. 1991), its
distribution coefficient into environmental organic matter is on
the order of 104 -106 (Benoit et al. 1999a, 1999b). O'Loughlin
et  al.  (2000)  report  similar  discrepancies for  organotin
compounds. In general distribution coefficients for metals into
fecal matter should be assigned values comparable to those used
to model the environmental fate and transport of metals whereas
metal distribution  coefficients for metals into  the non-lipid
organic matter of fish should be assigned values up to an order
of magnitude  higher to  reflect  the increased number and
availability of sulfhydryl binding  sites.

3.2. Parameters for Gill Exchange

To parameterize the gill exchange  model the fish'  s total gill area,
mean interlamellar distance, and mean lamellar length must be
specified. In general, each of these morphological variables is
dependent on the fish'  s body size according to the allometric
functions,
                    Sg = SlW°*                    (3-2)

                    d  =  dlWd2                    (3-3)

                     1  =  1^                     (3-4)
Although many authors have reported allometric coefficients and
exponents fortotal gill surface areas, parameters forthe latter are
seldom  available.  Parameters for fish' s mean interlamellar
distance, however, canbe estimated if the allometric functionfor
the density of lamellae on the gill filaments, p (number of
lamellae per mm of gill filament), i.e.,
                           TT7 P2                    /O C\
                    P  =  Pi w                      (-'•->)
is known. Fortunately, lamellar densities, like total gill areas, are
generally available in the literature. See Tables 2-4. BASS
estimates d1 and d2 from p, and p2 using the inter-specific re-
gression (n=28, r=-0.92)
                  d =  O.llSp-119                   (3-6)
To  overcome   the  scarcity  of  published  morphometric
relationships for lamellar lengths (see Table 5), BASS uses the
default inter-specific regression (n=90, r=0.92)
                 / = 0.0188 W0294                  (3-7)
Both of the preceding regressions are functional regressions
rather than simple linear  regressions (Rayner 1985;  Jensen
1986);  the  data  used for their calculation were drawn from
Saunders (1962), Hughes (1966), Steen and Berg (1966), Muir
and Brown (1971), Umezawa and Watanabe (1973), Galis and
Barel (1980), and Hughes et al. (1986).

To calculate lamellar Graetz and Sherwood numbers, BASS esti-
mates a chemical's  aqueous  diffusivity (cnf/s), using the
empirical relationship,
            D = 2.101xlO-7Ti"14v^0589
                                                   (3-8)

where v (cmVmol) is the chemical's molar volume (Hayduk and
Laudie  1974). The diffusivity of chemicals through the gill
membrane  which  is  needed  to  estimate  the membrane's
permeability km  is then assumed to equal  one  half of the
chemical's aqueous diffusivity (Piiper et al. 1986; Barber et al.
1988; Erickson and McKim 1990). The other quantity needed to
estimate km is  the thickness of the gill's water-blood barrier.
Based on the studies summarized in Table 6, BASS assumes a
default water-blood barrier thickness of approximately 0.0029
cm for all fish species and  then calculates km as the ratio of the
chemical's membrane diffusivity to the thickness of the gill's
water-blood barrier. These  assumptions imply that
                                                         18

-------
= 0.0116"^
                                                (3-9)
To  calculate ventilation/perfusion ratios  BASS estimates the
ventilation  volumes  (ml/hr)  of  fish from  their  oxygen
consumption rates assuming an extraction efficiency of 60% and
a saturated dissolved oxygen concentration (see Eq.(2-12)).
Perfusion rates (ml/hr) are estimated using
         Qp = (0.23 T - 0.78)  1.862  Wc
                          (3-10)
as the default for all species. Although this expression, in units
of L/kg/kr, was developed by Erickson and McKim (1990) for
rainbow trout (Oncorhynchus mykiss), it has been successfully
applied to other fish species (Erickson and McKim 1990; Lien
and McKim 1993; Lien et al. 1994).

The eigenvalues and bulk mixing cup coefficients needed to
parameterize Eq.(2-28) are interpolated internally by BASS from
matrices of tabulated eigenvalues and mixing cup coefficients
which encompass the range of  Sherwood  numbers  (i.e.,
 KNsh
-------
Table 2.  Summary of allometric coefficients and exponents for gill area and lamellar density for freshwater bony fishes and agnatha.
                   species
       Acipenser transmontanus
       Botia dario
       Botia lohachata
       Catostomus commersoni
       Cirrhinus mrigala
       Comephorus dyoowski
       Cottocomephorus grewingki
       Cottocomephoms inermis
       Cottus gobio
       Cottus gobio
       Ctenopharyngodon idella
       Cyprinus carpio
       Esox lucius
       Fundulus chrysotus
       Gambusia affinis
       Glossogobius giuris
       Hoplias lacerdae
       Hoplias malabaricus
       Hoplias malabaricus
       Ictalurus nebulosus
       Ictalums punctatus
       L ampetra fluviatilis
       Lampetra planeri
       Leiopotherapon unicolor
       Lepomis macrochims
       Macrognathus aculeatum
       Microptems dolomieui
       Mystus cavasius
       Oncorhynchus mykiss
       Oncorhynchus mykiss
       Oncorhynchus tshawytscha
Si
3.50
10.5
9.13
11.2
11.8
2.15
6.56
7.42
7.20
1.35
9.44
8.46
0.274
-
2.47
12.6
4.92
1.26
0.731
4.98
-
24.1
23.9
4.68
-
2.17
7.36
6.17
1.84
3.15
7.13
S2
0.849
0.716
0.700
0.587
0.816
0.675
0.91
0.918
0.849
1.29
0.774
0.794
1.24
1.18
0.842
0.516
0.81
1.14
1.25
0.728
-
1.03
0.689
1.04
-
0.733
0.819
0.915
1.13
0.932
0.922
f,
15.3
41.0
39.0
25.2
63.2
-
24.6
22.6
-
21.8
33.0
32.2
78.6
-
-
-
29.0
35.0
29.5
15.9
10.2
31.0
28.3
20.6
20.1
41.9
30.0
40.2
-
27.5
	
f2
-0.0475
-0.0460
-0.0055
-0.109
-0.129
~
-0.150
-0.110
~
-0.126
-0.0513
-0.0787
-0.222
~
~
~
-0.06
-0.090
-0.0600
-0.0917
-0.056
-0.123
-0.117
-0.0870
-0.098
-0.0690
-0.0615
-0.0970
~
-0.0639
	
             source
Burggrenetal. (1979)
Singh etal. (1988)
Sharmaetal. (1982)
Saunders (1962)
Roy and Munshi (1986)
Jakubowski (1993)
Jakubowskietal. (1995)
Jakubowski et al. (1995)
Jakubowski etal. (1995)
Liszka (1969) and Starmach (1971)
Jakubowski (1982)
Oikawa and Itazawa (1985)
de Jager et al. (1977) and
Burnside (1976)
Murphy and Murphy (1971)
Singh and Munshi (1985)
Fernandes et al. (1994)
Fernandes et al. (1994)
Fernandes and Rantin (1985)
Saunders (1962)
Barber (2000)
Lewis and Potter (1976)
Lewis and Potter (1976)
Gehrke (1987)
Barber (2000)
Ojha and Munshi (1974)
Price (1931)
Ojha etal. (1985)
Niimi and Morgan (1980)
Hughes (1984)
Romough and Moroz (1990)
                                                      20

-------
Orechromis alcalicus
Orechromis niloticus
Oryzias latipes
Piaractus mesopotamicus
Plagioscion squamosissimus
Pomoxis nigromaculatus
Prochilodus scrofa
Stizostedion vitreum
Tinea tinea
Tinea tinea
11.1    0.789   38.4    -0.143     Hughes (1995)
6.35    0.777   32.9    -0.0545    Kisia and Hughes (1992)
4.65    0.446   43.5    0.0        Umezawa and Watanabe (1973)
5.65    0.769   40.2    -0.033     Seven etal. (1997)
12.0    0.70    37.0    -0.07      Mazonet al. (1998)
                18.4    -.074      Barber (2000)
16.2    0.72    43.0    -0.12      Mazonet al. (1998)
0.796   1.13    -      -         Niimi and Morgan (1980)
28.5    0.522   20.3    0.0160     Hughes (1972)
        0.698   25.5    -0.0300    Hughes (1972)
                                                21

-------
Table 3. Summary of allometric coefficients and exponents for gill area and lamellar density for cartilaginous and marine boney
        fishes.
                    species
        Acanthopagrus australis
        Alopias vulpinus
        Blennius pholis
        Carcharodon carcharias
        Carcharhinus obscurus
        Carcharhinus plumbeus
        Coryphaena hippurus
        Fundulus similis
        Isurus oxyrinchus
        Katsuwonus pelamis
        Morone saxatilis
        Opsanus tau
        Platichthys flesus
        Prionace glauca
        Scomber scombrus
        Scyliorhinus canicula
        Scyliorhinus stellaris
        Seriola quinqueradiata
        Thunnus thynnus
        Torpedo marmorata
Si
2.40
2512.
7.63
42.7
6.17
24.5
52.1
-
57.5
52.2
-
5.61
6.36
5.50
4.24
2.62
6.21
22.9
24.4
1.17
S2
0.788
0.410
0.849
0.770
0.880
0.740
0.713
0.850
0.740
0.850
-
0.790
0.824
0.880
0.997
0.961
0.779
0.686
0.901
0.937
ti
-
229.
28.3
27.5
33.8
23.4
33.8
-
50.0
59.0
17.0
16.0
-
12.9
27.1
17.1
30.3
38.5
63.2
34.2
12
-
-0.340
-0.139
-0.150
-0.160
-0.130
-0.0360
~
-0.200
-0.0759
-0.069
-0.0750
~
-0.0900
0.0230
-0.0710
-0.167
-0.0419
-0.0938
-0.167
             source
Roubal (1987)
Emery and Szczepanski (1986)
Milton (1971)
Emery and Szczepanski (1986)
Emery and Szczepanski (1986)
Emery and Szczepanski (1986)
Hughes (1972)
Burnside (1976)
Emery and Szczepanski (1986)
Muir and Hughes (1969)
Barber (2000)
Hughes and Gray (1972)
Hughes and Al-Kadhomiy (1986)
Emery and Szczepanski (1986)
Hughes (1972)
Hughes (1972)
Hughes etal. (1986)
Kobayashietal. (1988)
Muir and Hughes (1969)
Hughes (1978)
                                                       22

-------
Table 4. Summary of allometric coefficients and exponents for gill area and lamellar density for air-breathing fishes.
                   species
        Anabas testudineus
        Boleophthalmus boddaerti
        Boleophthalmus boddaerti
        Boleophthalmus boddaerti
        Channa punctata
        Clarias batrachus
        Clarias mossambicus
        Cobitis taenia
        Hoplerythrinus unitaeniatus
        Hypostomus plecostomus
        Lepidocephalichthys guntea
        Lepisosteus oculatus
        Lepisosteus osseus
        Lepisosteus platostomus
        Noemacheilus barbatulus
        Periophthalmodon schlosseri
        Periophthalmodon schlosseri
        Periophthalmus chrysospilos
        Rhinelepis strigosa
        Saccobranchus fossilis
Si
5.56
2.81
0.927
6.79
4.70
2.28
0.958
4.67
5.99
4.36
4.94
3.35
4.77
3.01
3.60
3.00
1.00
0.976
6.25
1.86
S2
0.615
0.709
1.05
0.481
0.592
0.781
0.971
0.864
0.66
0.666
0.745
0.753
0.699
0.793
0.577
0.934
0.931
0.958
0.757
0.746
f,
36.5
24.6
26.6
23.1
36.0
25.4
30.7
45.5
48.0
17.3
45.0
18.1
20.9
15.3
36.4
27.0
47.9
30.2
12.3
31.6
f2
-0.152
-0.0830
-0.229
-0.0307
-0.138
-0.0830
0.0909
0.0
-0.16
0.081
-0.221
-0.0476
-0.0691
-0.0236
0.0
-0.0484
-0.0518
-0.237
0.020
-0.0950
              source
Hughes etal. (1973)
Nivaetal. (1981)
Hughes and Al-Kadhomiy (1986)
Low etal. (1990)
Hakim etal. (1978)
Munshietal. (1980)
Maina and Maloiy (1986)
Robotham(1978)
Fernandes et al. (1994)
Perna and Fernandes (1996)
Singh etal. (1981)
Landolt and Hill (1975)
Landolt and Hill (1975)
Landolt and Hill (1975)
Robotham(1978)
Yadavetal. (1990)
Low etal. (1990)
Low etal. (1990)
Santos etal. (1994)
Hughes (1972)
                                                       23

-------
Table 5. Summary of coefficients and exponents for lamellar lengths.






               species                          lj           12



               Hoplias lacerdae                 0.012       0.23




               Hoplias malabaricus             0.006       0.36




               Hoplerythrinus unitaeniatus       0.014       0.22




               Ictalurus punctatus               0.00465     0.265




               Lepomis macrochirus             0.00364     0.234




               Morone saxatilis                 0.00474     0.202




               Piaractus mesopotamicus         0.0069      0.223




               Pomoxis nigromaculatus          0.00255     0.257




               Rhinelepis strigosa               0.0422      0.231
source



Fernandes et al (1994)



Fernandes et al (1994)



Fernandes et al. (1994)



Barber (2000)



Barber (2000)



Barber (2000)



Severietal. (1997)



Barber (2000)



Santos etal. (1994)
                                                        24

-------
Table 6. Summary of studies reporting water-blood barrier thickness for freshwater and marine fishes.
                               source
                   Dube and Munshi (1974)
                   Hughes (1972)
                   Hughes and Morgan (1973)
                   Hughes and Umezawa (1983)
                   Hughes etal. (1986)
                   Kobayashietal. (1988)
                   Munshi et al. (1980)
                   Ojha and Munshi (1974, 1976)
                   Ojhaetal. (1982)
                   Ojha etal. (1985)
                   Piiperetal. (1986)
                   Roy and Munshi (1987)
                   Sharmaetal. (1982)
                   Singh and Munshi (1985)
                   Singh etal. (1981)
                   Singh etal. (1988)
                   Steen and Berg (1966)
                   Stevens (1992)
                   Tuuralaetal. (1998)
                   species
Anabas testudineus
Tinea tinea
various species
Phrynelox tridens, Seriola quinqueradiata
Scyliorhinus stellaris
Seriola quinqueradiata
Glorias batrachus
Macrognathus aculeatum
Garra lamta
Mystus cavasius
Scyliorhinus stellaris
Cirrhinus mrigala
Botia lohachata
Glossogobius giuris
Lepidocephalichthys guntea
Botia dario
various species
Sciaenops ocellatus
Anguilla  anguilla
                                                        25

-------
Table 7. Sources of bioenergetic and growth for selected fish species.
species
Alosa pseudoharengus
Ambloplites rupestris
Ameiurus sp.
Ctenopharyngodon idella
Cyprinodon sp.
Cyprinus carpio
Dorosoma cepedianum
Esox lucius
Gambusia affinis
Lepomis sp.
Micropterus salmoides
Micropterus dolomieu
Morone saxatilis
Oncorhynchus mykiss
Oncorhynchus nerka
Oncorhynchus tshawytscha
Osmerus mordax
Perca flavescens
Phoxinus phoxinus
Pimephales promelas
Ptychocheilus oregonensis
Pungitius pungitius
Pylodictis olivaris
Salmo trutta
Salvelinus namaycush
Stizostedion canadense
Stizostedion vitreum vitreum
source
Stewart and Binkowski (1986)
Roell and Orth (1993)
Glass (1969), Campbell and Branson (1978)
Wiley and Wike (1986)
Nordlie et al. (1991), Jordan et al. (1993)
Glass (1969), Oikawa and Itazawa (1984), Garcia and Adelman (1985)
Pierce et al. (1981), Drenner et al. (1982)
Diana (1982a, 1982b), Salam and Davies (1994)
Murphy and Murphy (1971), Shakuntala and Reddy (1977), Mitz and Newman (1989)
Wohlschlag and Juliano (1959), O'Hara (1968), Pierce and Wissing (1974), El-Shamy (1976),
Evans (1984)
Beamish (1970, 1974), Niimi and Beamish (1974), Tandler and Beamish (1981)
Roell and Orth (1993)
Hartman and Brandt (1995a)
Kutty (1968), Rao (1968), Staples and Nomura (1976), Muller-Feuga et al. (1978), Grove et al.
(1978), Rand etal. (1993)
Brett (1971), Beauchamp et al. (1989), Stewart and Ibarra (1991)
Stewart and Ibarra (1991)
Lantry and Stewart (1993)
Norstrom et al. (1976), Kitchell et al. (1977), Post (1990), Rose et al. (1999), Schaeffer et al.
(1999)
Wootton et al. (1980), Cui and Wootton (1988)
Wares and Igram (1979), Duffy (1998)
Petersen and Ward (1999)
Cameron etal. (1973)
Roell and Orth (1993)
Glass (1969), Elliott (1972, 1975a, 1975b, 1976b)
Stewart et al. (1983), Thomann and Connolly (1984)
Minton and McLean (1982)
Kitchell et al. (1977), Tarby (1980), Madon and Culver (1993), Rose et al. (1999)
                                                           26

-------
Figure 2. First eigenvalue for Eq.(2-28) as a function of gill Sherwood number and ventilation/perfusion ratio.
                                                          27

-------
Figure 3. Second eigenvalue for Eq.(2-28) as a function of gill Sherwood number and ventilation/perfusion ratio.
                                                         28

-------
Figure 4. First bulk mixing cup coefficient for Eq.(2-28) as a function of gill Sherwood number and ventilation/perfusion ratio.
                                                          29

-------
Figure 5. Second bulk mixing cup coefficient for Eq.(2-28) as a function of gill Sherwood number and ventilation/perfusion ratio.
                                                         30

-------
                                             4. BASS User Guide
Although BASS versions 1.0 and 1.1 were written in Fortran 77,
BASS version 2.0 and higher is coded in Fortran 95. The model
enables users to  simulate the population and bioaccumulation
dynamics of age-structured fish communities using a temporal
and  spatial  scale  of resolution of a day  and a hectare,
respectively. BASS currently ignores the migration of fish into
and out of this simulated hectare. The duration of any species'
age class can be specified as either a month or a year. This
flexibility enables users to simulate small, short-lived species
such as daces, live bearers, and minnows with larger, long-lived
species such  as bass,  perch,  sunfishes,  and  trout.   The
community's food web is  specified by defining one or  more
foraging classes for each  fish species based on  either  body
weight, body length, or age. The user then specifies the dietary
composition of each of these foraging classes as a combination
of  benthos,  incidental  terrestrial  insects,   periphyton,
phytoplankton, zooplankton, and/or other fish species including
its own. Presently the standing stocks of all nonfish prey are
handled only  as external forcing  functions rather than as
simulated state variables.

Although BASS was developed to simulate the bioaccumulation
of chemical pollutants within a community or ecosystemcontext,
it can  also be used to  simulate population  and community
dynamics of fish assemblages that are not exposed to chemical
pollutants. For example, in its present form BASS could be used
to  simulate the population and  community dynamics of fish
assemblages that are subjected to altered thermal regimes that
might be associated with a variety of hydrological alterations or
industrial activities.  BASS could also be used to investigate the
impacts of exotic species or sport fishery management programs
on  population  or  community  dynamics   of   native   fish
assemblages.

The model's output includes:

•       Summaries  of  all   model  input  parameters  and
        simulation controls.

•       Tabulated annual  summaries for the bioenergetics of
        individual fish by species and age class.

•       Tabulated  annual  summaries  for  the  chemical
        bioaccumulation within individual fish by species and
        age class.

•       Tabulated annual summaries for the community level
        consumption, production, and mortality of each fish
        species by age class.
•       Plotted annual dynamics of selected model variables as
        requested by the user.

BASS version 2.1 is still a beta test version. Please report any
comments, criticisms,  problems, or suggestions regarding the
model software or user manual to

        Craig Barber
        Ecosystems Research Division
        U.S. Environmental Protection Agency
        960 College Station Road
        Athens, GA 30605-2700
        office:  706-355-8110
        FAX:   706-355-8104
        e-mail:  barber.craig@epa.gov

4.1. Summary of New Features Available in BASS
version 2.1

The following features that were unavailable in BASS versions
1.x are now active:

•       There  are  now no restrictions  to  the number of
        chemicals that can be simulated.

•       There are now  no restrictions to  the number of fish
        species that can be simulated.

•       There are now no restrictions to the number of cohorts
        that fish species may have.

•       There are now no restrictions to the number of feeding
        classes that fish species may have (see the command /
        FEEDING_OPTIONS).

•       There are now no restrictions to the number of foraging
        classes that fish species may have (see the command /
        ECOLOGICAL_PARAMETERS).

•       Improved 3-dimensional and 2-dimensional plots of
        selected state variables are available using the software
        package DISLIN.

BASS'S output tabulations have also been reformatted, and
several input commands have been given new  syntax.

New features  of BASS version 2.1 that were unavailable in
version 2.0 include:
                                                         31

-------
 •      The ability to integrate BASS'S differential equations
        using either a simple Euler  method or a fifth-order
        Runge-Kutta method with adaptive step sizing. In BASS
        version 2.1 the default method of integration is the
        Runge-Kutta method.

•       The ability to simulate biotransformation of chemicals
        with or without daughter products.

Regarding BASS'S Euler and Runge-Kutta integrators, the user
should realize that these methods offer the user two distinctly
different options with respect to  software performance and
execution. Although Euler methods often allow for fast model
execution, these methods cannot assess the accuracy  of their
integration. Runge-Kutta methods, on the  other hand, can
monitor the accuracy of their integration but at the  cost of
increased execution time. Fortunately, however, this additional
computational  burden can often be significantly reduced by
employing adaptive step sizing. BASS'S Runge-Kutta integrator
is patterned on the fifth-order Cash-Karp Runge-Kutta algorithm
outlined by Press et. al. (1992).

4.2. Input File Structure

The general structure of a BASS' s input file is as follows

        / command!      argument(s)
        / command2      argument(s)

        / command,,      argument(s)
        /end

The leading slash (/) identifies the line as a command. Blanks or
tabs before or after the slash are not significant. The keyword or
phrase (e.g., commandn ) that follows each slash identifies the
type  of data being specified by that record. Keywords must be
spelled in full without embedded blanks and must be separated
from the record's remaining information by at least one blank or
tab. Argument may be an integer (e.g., 7), a real number (e.g., 0,
3.7e-2, 1.3, etc.), or a character string. If a command allows
multiple arguments, each  argument must be separated by a
semicolon.  Commands may be continued by  appending an
ampersand  (&) to the line, e.g., the following two commands
lines are equivalent

        / command      arg^ arg2; arg3; &
                        arg4; arg5; arg6
        / command
                           ^ arg2; arg3; arg4; arg5; arg6
Because each record is transliterated to lower case before being
decoded, the case of the input file is not significant. Likewise,
spacing within a command is not significant because consecutive
blanks or tabs are collapse into a single blank. The maximum
length of a command line, including continuation lines, is 1024
characters.

An exclamation mark (!) in the first column of a line identifies
the line as a comment. An exclamation mark can also be used
anywhere in the record field to start an end-of-line comment, i.e.,
the remainder of the line, including the exclamation mark, will
be ignored.

Commands  are  broadly  classified  into   three  categories:
simulation control parameters, chemical parameters, and fish
parameters. Simulation control parameters provide information
that is applicable to the simulation as a whole, e.g., length of the
simulation, the  ambient water temperature, nonfish standing
stocks, and output options. Chemical parameters specify not only
the chemical's physico-chemical properties (e.g., the chemical's
molecular weight, molecular volume, n-octanol/water partition
coefficient,  etc.)  but also exposure  concentrations  in the
environment (i.e., in water, sediment, benthos, insects, etc.). Fish
parameters identify the fish's taxonomy (i.e., genus and species),
feeding and metabolic demands, dietary composition, predator-
prey relationships, gill morphometrics, body composition, initial
weight, initial whole body concentrations for each chemical, and
initial  population  sizes.  In  the  following sections,  these
commands are described alphabetically by class.

The last command in any BASS input file must be /END. This
command terminates program input and any text/commands
following it  will be  ignored. BASS checks the  syntactical
accuracy of each input command as it is read. If no syntax errors
are encountered, B AS s then checks the specified input parameters
for completeness and internal inconsistency.

To facilitate easier data management when analyzing multiple
simulations of similar scenarios, a user can also specify blocks
of BASS input commands using include statements of the form

        # include 'filename'

For example, a  BASS input file that has all of its chemical and
fish data stored in separate files might appear as follows
        ! file: example file with include statements
        I
        /simulation_control
        / command argument, simulation control command 1
        / command argument, simulation control command 2
        / command argument, simulation control command 3
        # include 'data^for_chemical_r
                                                         32

-------
        # include 'data^for_chemical_2'
        # include 'datajbrjish_r
        # include 'datajbrjish_2'
        # include 'data^for^fish_3'
        # include 'data^for^fish_4'
        /end

Users are strongly recommended to make use of BASS'S include
file capabilities. A recommended file and subdirectory structure
for using and managing BASS include files is discussed in detail
in Section 4.4.

4.2.1. Simulation Control Commands

These  commands establish the  length of the  simulation and
BASS'S integration step, the ambient water temperature,  the
availability  of benthos,  incidental  terrestrial insects  and
plankton,  the  community's  water  level, and  various  output
options. These data are specified by the following block of
twelve commands
        / SIMULATION_CONTROL
        /HEADER
        / LENGTH_OF_SIMULATION
        / MONTHJTO
        / NSTEPS
        /TEMPERATURE
        / WATER_LEVEL
        / BIOTA
        / ANNUAL_OUTPUTS
        / ANNUAL_PLOTS
        / SUMMARY_PLOTS
        /FGETS
string
string
string
integer
string
string
stringy ... \stringn
integer
stringy ...; stringn
stringy ...;stringn
The  command  /SIMULATION_CONTROL must be  the  first
command in the block since it identifies the start of these data.
The  order of the  remaining commands,  however,  is not
significant. The use of these commands will now be described
in alphabetical order. See Appendix D for an example of the use
of these commands.

• /ANNUAL_OUTPUTS integer

This command specifies the time interval, in years, between
BASS'S annual tabulated and plotted outputs. This number must
be an non-negative integer. BASS assumes a default value of zero
which signifies that no annual outputs will be generated. This
command is optional.

• /ANNUAL_PLOTS string,;... ; stringn

This command specifies the variables whose annual dynamics
will  be  plotted  for the  years  specified  by  command
/ANNUAL_OUTPUTS. The options may be specified one per card,
or all in one card, separated by semicolons. Valid options are:

afish(sfri«g) to generate plots of each species' total aqueous
phase chemical activity as a function of time (day of year) and
the species' age,  length, or weight class;

\)af(string) to generate plots of each species' bioaccumulation
factor (i.e., the ratio Cf/ CJ for each chemical as a function of
time (day of year) and the species' age, length, or weight class;

bmf'(string) to generate plots of each species' biomagnification
factor (i.e., the ratio Cf/Cprey) for each chemical as a function of
time (day of year) and the species' age, length, or weight class;

cfish(string) to  generate plots of each species'  whole body
concentration (ppm) for each chemical as a function of time (day
of year) and the species' age, length, or weight class;

pop (string) to generate plots of each species' population density
(ind./ha) as a function of time (day of year) and the species' age,
length, or weight class;

wt(string) to generate plots of each species' whole body weight
(g(Fw)/fish) as a  function of time (day of year) and the species'
age, length, or weight class;

where string equals "age", "length" or "weight". Each age class
or cohort of the species is assigned to  one of five size classes
that are defined by BASS based on the species' largest/oldest and
smallest/youngest individuals.

• /BIOTA string,;... ; stringn

This command specifies nonfish standing stocks that are prey for
the simulated fish assemblage. Valid options are:

benthos|jw«&s]  = string to generate benthic standing stocks
according to the function string whose units yunits must be
dimensionally equivalent to g(DW)/m2.

insects \yunits] = string to generate incidental terrestrial insect
standing stocks according to the function string  whose units
yunits must be dimensionally equivalent to g(DW)/nf.

periphyton|jwmYs] = string to generate periphyton standing
stocks according to the function string whose units yunits must
be dimensionally equivalent to g(DW)/m2.

phytoplankton|jMwiYs] = string to generate phytoplankton
standing stocks according to the function string  whose units
                                                         33

-------
yunits must be dimensionally equivalent to g(DW)/L.

zooplankton|jwwiYs] = string to generate zooplankton standing
stocks according to the function string whose units yunits must
be dimensionally equivalent to g(DW)/L.

Valid specifications for these biotic resource functions are

function_name\yunits] = a to generate the a constant  prey
standing stock of a (yunits) for the simulation.

function_name\yunits] =  a  +  P*sin(oo  + 
-------
pop(string) to generate plots of each species' population density
(ind./ha)  as  a function of time (day  of simulation)  and the
species' age, length, or weight class;

where string equals "age", "length" or "weight". Each cohort of
the species is assigned to one of five size classes that are defined
by   BASS  based  on  the   species'   largest/oldest  and
smallest/youngest individuals.

• /TEMPERATURE String

The command specifies the ambient' s water temperature. Valid
options for this command are:

temp [celsius] = a  to generate a constant ambient water tem-
perature for the simulation.

temp [celsius] = a, + p*sin(oo  + 
-------
 sediments or via the ingestionof benthic invertebrates, incidental
 terrestrial  insects,  or plankton.  Exposure  concentrations
 specified by these  options  are  assumed  to  be completely
 bioavailable to  the fish. For example, water concentrations are
 assumed to be  actual dissolved concentrations and not total
 water concentrations which include particle-bound chemical. If
 multiple options are selected, each option must be separated by
 a semicolon. Valid options are:

 cbnths|jM«&s]  = string to generate potential dietary exposures
 to fish via benthic organisms according to the function string.

 cinsct|jM«&s] = stringto generate potential dietary exposures to
 fish via incidental terrestrial insects according to the function
 string.

 cphytn|jww&s] = stringto generate potential dietary exposures
 to fish via periphyton according to the function string.

 cpplnk|jwmYs] = string to generate potential dietary exposures
 to fish via phytoplankton according to the function string.

 csdmnt|jwmYs] = string to generate sediment exposure concen-
 trations according to the function string.

 cwater|jwmYs] = string to generate aqueous exposure concen-
 trations according to the function string.

 czplnk\yunits]  = string to generate potential dietary exposures
 to fish via zooplankton according to the function string.

 The concentration units for each exposure function are specified
 within the  indicated brackets. As  previously  noted for  the
 simulation control functions, unless specified otherwise BASS
 assumes that the first day of simulation is April 1 and that the
 365-th simulation day is  March 31 for all the time dependent
 exposure functions discussed below.  This assignment can be
 changed using the command /MONTH_TO.

 Valid expressions for dietary exposures viabenthos, periphyton,
 phytoplankton,  or zooplankton and for benthic sediments are:

function_name\yunits] = a to generate a constant concentration
 of toxicant in benthos, periphyton, phytoplankton, sediment, or
 zooplankton.

function_name\yunits\  =   a*cwater[xunits]  to   generate
 chemical concentrations in benthos, periphyton, phytoplankton,
 sediment, or zooplankton as  a chemical equilibrium  with the
 ambient environmental water. If this equilibrium is assumed to
 be thermodynamic, then the coefficient a generally is equal the
 product  of the  component's dry organic  fraction  and  the
chemical's Kow.

function_name\yunits\ = file(filename) to read and interpolate
the  concentration  of  toxicant  in  benthos,  periphyton,
phytoplankton, sediment, or zooplankton from the file filename.

Valid expressions for insect dietary exposures are:

cinsct\yunits ]= a to generate a constant concentrations of the
toxicant in incidental terrestrial insects.

cinsct|jM«&s  ] = file(ftlename)  to  read  and interpolate  the
concentration of the toxicant in incidental terrestrial insects from
the file filename.

Valid expressions for direct aqueous exposures are:

cwater \yunits] = a to generate a constant aqueous concentration
for the chemical of concern.

cwater\yunits]  =  a*csdmnt[xunits]  to  generate  aqueous
exposure concentrations as  a chemical equilibrium with  the
benthic sediments. If this equilibrium is assumed to be thermo-
dynamic, then the coefficient a generally is assumed to equal the
product of the sediment's organic fraction and the chemical's Koc.

cw&ter\yunits]   =  cc+p*exp(y*t[.v;wmYs])  to   generate  an
exponential dissolved chemical water concentration where a and
P have units ofyunits and y has units of l/xunits. This option
can be used to simulate a chemical spill or one time application
of a pesticide.

cw&ter\yunits]  =  a.+fi*sin((d+fy*t[xunits]) to  generate a
sinusoidal dissolved chemical water concentrations where a is
the mean dissolved chemical water concentration (yunits) (over
one period), P is the amplitude (yunits),  GO is its phase angle
(radians), and 
-------
This optional command specifies species specific LC50's for the
chemicals of concern. Valid string options are:

LC50 [units] (fish_name) = a

LC50 [units] (fish_name) = a*Kow[-]Ay

where  Kow[-]  is  the  chemical's  n-octanol/water partition
coefficient  and fishjiame is the common name  of the fish
species to be simulated. BASS converts these user supplied LC50's
into their corresponding  aqueous chemical activities and then
uses the  geometric mean of these lethal activities to  trigger
mortality during the simulation.

If the user desires, simulation of mortality associated with the
accumulation a lethal aqueous chemical activity can be turned
off by  using the command line option "-1" as discussed in
Section 4.5. When this is done, however, BASS still calculates
the fish's total aqueous phase chemical activity and reports it as
a fraction of the fish's  estimated  lethal chemical activity to
provide the user with simple but useful monitor  of the total
chemical status of the fish.

• /LOG_AC real number

This command specifies the  Iog10  of the chemical's aqueous
activity coefficient. For organic chemicals, if this parameter is
not specified,   BASS will estimate  the chemical's  activity
coefficient using its melting point and n-octanol/water partition
coefficient.

• /LOG_KBl real number

This command specifies the Iog10 of metal's binding constant for
non-lipid organic matter (see Eq.(2-6)). This parameter is input
only for metals and organometals.

• /LOG_KB2 real number

This command specifies the Iog10 of a metal's binding constant
for refractory organic matter. This parameter is used to calculate
metal binding to the fish's dry fecal matter and input only for
metals and organometals.

• /LOG_P real number

This command specifies  the chemical's Iog10 Kow, where Km is
the n-octanol/water  partition  coefficient.  /LOG_P  must be
specified for all organic chemicals.

• /MELTING POINT real number
The command specifies the chemical's melting point (Celsius).
This datum,  together with the  chemical's logP, is  used to
calculate the aqueous activity coefficient for organic chemicals
when that parameter is not specified by the user. See Yalkowsky
etal. (1983)

• /METABOLISM string, ; ... ; stringn

This optional command  specifies  species specific rates  of
biotransformation for the chemical  of concern. Valid strings
options are:

BT [units] (fish_name, chemical_name) = a

BT [units] (fish_name, chemical_name) = a*Kow[-]Ay

BT [units] (fish_name, none) = a

BT [units] (fish_name, none) = a*Kow[-]Ay

where BT is  the whole body referenced biotransformation rate
km in Eq.(2-46);  Kow[-] is the chemical's  n-octanol/water
partition coefficient; w&fishjiame is the common name of the
fish species that can metabolize  the chemical of concern, and
chemical jiame is the name of the daughter product generatedby
the metabolism of chemical. If the user does not wish to simulate
daughter products because they are insignificant or assumed to
be harmless, chemical _name can be assigned the value none.
When daughter products are specified, the user must specify all
physical chemical properties of the identified by-product in the
same way  that the physical chemicals properties of the parent
compound are specified.

• /MOLAR_VOLUME real number

The  command  specifies the chemical's  molecular  volume
(cmVmol)  which is used to calculate the chemical's aqueous
diffusivity, i.e.,

                       2-101xl(r7
                 D -
                         1.4 V0.589
where D is the toxicant's aqueous diffusivity (cmVsec), t| is the
viscosity of water (poise), and v is the molecular volume of the
chemical (cnf/mol) (HaydukandLaudie 1974). The viscosity of
water over its entire liquid range is represented with less than
1% error by
        f %,]    1.37(7--20) +  8.36xl(T4(r-20)2  ,   .
    Sw  (~^)                 109^              (^'2)
where % is the viscosity (centipoise) at temperature T (Celsius),
and r|20 is the viscosity of water at 20 °C (1.002 centipoise)
(Atkins 1978).
                                                        37

-------
string
string
string,;
string,;
s
TERS
TERS
:ERS
...;stringn
...; string,,
string,; ..
string,; ..
string,; ..
string,; ..
.;stringn
.;stringn
.;stringn
:,stringn
• /MOLAR_WEIGHT real number

The command specifies the chemical's molecular weight (g/mol).

4.2.3. Fish Input Commands

Model parameters for each fish species of interest are specified
by a block of ten commands, i.e.,

        /COMMON_NAME         String
        /SPECIES        string
        /AGE_CLAS S_DUR ATION
        /SPAWNING_PERIOD
        /FEEDING_OPTIONS
        /INITIAL_CONDITIONS
        /ECOLOGICAL_PARAMETERS
        /COMPOSITIONAL_PARAMETERS
        /MORPHOMETRIC_PARAMETERS
        /PHYSIOLOGICAL_PARAMETERS

The command /COMMON_NAME must be the first command in
the block since it is the identifier for the start of a new set of fish
parameters.  The order of  the remaining  commands is not
significant. See Appendix D for examples of the commands
described below.

• /AGE_CLASS_DURATION String

This command is used to specify the duration of each age class.
Two character strings, i.e., "month" and "year", are recognized
as valid options.

• /COMMON_NAME string

This command specifies the start of input data for a fish species.
The command's specified common name  string is used for
model output and as a  label  for  specifying the  dietary
composition of other fish species. Each common name must be
a single character string without embedded blanks. If a two-part
name  is desired, the user should use  an underscore  "_" as a
separatingblank. See the diet optionforthe command/ECOLOGI-
CAL_PARAMETERS.

• /COMPOSITIONAL_PARAMETERS string,;... ; stringn

This command specifies aqueous and lipid fractions of the fish.
Valid options which must be separated by semicolons are:

pa[-] = a + P*pl[-] which specifies the fish's aqueous fraction
as a linear function of the fish's lipid fraction.

pl[-] = a*W[xunits] Ap which specifies the fish's lipid fraction
as an allometric function of its body weight. If a fish's average
lipid content is independent of its body weight (i.e.,  p equals
zero), however, this parameter can be specified simply as
\A\yunits] = a..

where a and p are integer or real numbers.

• /ECOLOGICAL_PARAMETERS string,;... ; string,,

This command specifies the ecological parameters that describe
the  fish's trophic interactions, non-predatory mortality,  and
recruitment. Valid options that must be separated by semicolons
are:

diet(a< string 
-------
mls\yunits] = a which specifies the species' maximum longevity
or life span.

nm\yunits] = a*W[jcw«&s]Ap which specifies a non-predatory
mortality rate for fish whose body weight is W[xunits]', yunits
must be dimensionally equivalent to I/year. If the mortality rate
offish is independent of their body weight (i.e., P equals zero),
however, this parameter can be specified simply as nm\yunits]
= a.

tl_ro\yunits] = a which specifies the species' minimum total
length when it reaches sexual maturity or its first reproduction.

rbi[-] = a which specifies the species' reproductive biomass
investment, i.e., grams gametes per gram spawning fish.

wl\yunits] = a*L[jcwmYs]Ap which specifies the fish'  s  live
weight as an allometric function of its total length.

yoy\yunits] = a which specifies the live weight offish recruited
into the population as age class 0.

• /FEEDING_OPTIONS string,;... ; string,,

This command instructs BASS how to calculate ingestion for a
particular age or size  range of fish.  Valid options  for this
command are

allometric(a< string 
-------
  I /PHYSIOLOGICAL_PARAMETERS string,;... ; stringn
Required only if the feeding option holling(-) is selected.
This command specifies the species' physiological parameters
for simulating its growth. Each string specifies a physiological
parameter of the fish as a constant or temperature-dependent
power function of its body weight. In particular,

ae_plant[-] = a which specifies the fish's assimilation efficiency
for periphyton and phytoplankton.

ae_invert[-]  =  a  which specifies  the  fish's  assimilation
efficiency for benthos, insects, and zooplankton.

ae_fish[-] = a which specifies the fish's assimilation efficiency
for fish.
             =   a*G[xunits] AP   *exp(y*(T[celsius]-
T0))*h(T0,T1,T2) which specifies the fish's gastric evacuation
where G is the mass of food resident in the intestine, yunits must
be dimensionally equivalent to g(ow)/day. In general, y = !/2, %,
or 1 (Jobling 1981). This parameter is required only if the
feeding option holling(-) is selected.

mf[yunits]   =   a*W[jc«/nYs] Ap*exp(y*(T[celsius]-
T0))*h(T0,T1,T2) which specifies the fish's maximum filtering
rate, yunits must be dimensionally equivalent to L/day. Required
only if the feeding option clearance(-) is selected.

mi[yunits] = a*W[xunits] Ap*exp(y*(T[celsius]-
T0))*h(T0,T1,T2) which specifies the fish's maximum ingestion.
yunits must be dimensionally equivalent to g(DW)/day. Required
only if the feeding option allometric(-) is selected.

rq[-] = a which specifies the fish's respiratory quotient; rq =
L(CO2) respired / L(O2) consumed.

rt:std[-] = a which specifies the ratio of afish's routine respira-
tion to its standard respiration; rt:std = (routine O2 consumption)
/ (standard O2 consumption). BASS assumes a default value equal
2.

sda:in[-] = a which specifies the ratio of a fish's SDA to its
ingestion. BASS assumes a default value equal 0. 17.

sg[yunits]   =   a*W[jc«/nYs] AP  *exp(y*(T[celsius]-
T0))*h(T0,Tj,T2) which specifies the fish's specific growth rate.
yunits must be dimensionally equivalent to day"1. Required only
if the feeding option linear(-) is selected.
so[yunits]   =   a*W[.x;wwi£s]Ap   *exp(y*(T[celsius]-
T0))*h(T0,T!,T2) which specifies the fish's standard oxygen con-
sumption, yunits mustbe dimensionally equivalent to mg(O2)/ hr
ormg(O2)-g(FW)-1-hr'1.

st\yunits]   =   a*MV[xunits] Ap   *exp(y*(T[celsius]-
T0))*h(T0,T!,T2) which specifies the time to satiation when
feeding with an initially empty stomach. See option sm [•] above.
Required only if the feeding option holling(-) is selected.
where
                           T2-T

                          T -T
                          -*- o  -*- n
                                                                                                            (4-3)
sm[yunits]  =  a*V/[xunits] AP   *exp(y*(T[celsius]-
T0))*h(T0,Tj,T2) which specifies the size of the satiation meal
consumed during the interval (0, st]. See option "st[-]" below.
where T, is the temperature at which each particular process's
rate is maximal,  T2 is the upper temperature at which the process
is  no longer operative,  and T0 is the low  end reference
temperature that is used to specify the process's Q10 response.
Specification of the hyperbolic function hfT^TpT^ is optional
in which case the specification of the reference temperature T0
is also optional. Consequently, all  of the above temperature
dependent power functions can also be specified simply as

            oc*W[xM«/fc]Ap *exp(y*T[celsius])

As noted for the fish's morphometric parameters, if the exponent
P equals  zero  for any  of   parameters identified as being
allometric power functions, the resulting termW[.v;wmYs] A0 does
not have to be specified. If a required parameter is not specified,
the program will terminate with an appropriate message.

• /SPAWNING_PERIOD string

This command  specifies the months during which spawning
occurs. Valid character strings for this command are either the
name of a month or the names of two months separated by a
hyphen. For example,

        /SPAWNING_PERIOD  may  OR

        /SPAWNING_PERIOD  april-june

The names of the months must be spelled out in full.

• /SPECIES string

This command specifies the scientific name (genus and species)
                                                        40

-------
of the fish to be modeled. When this command is encountered,
BASS  uses the specified  scientific name to assign default
ecological, morphological, and physiological parameters for the
species of interest. These default parameters are then updated
with   the   data   that   the   user   inputs   via  the
/ECOLOGICAL_PARAMETERS, /MORPHOMETRIC_PARAMETERS, and
/PHYSIOLOGICAL_PARAMETERS   commands.  This  option,
however, is not implemented in BASS version 2.1.
4.2.4. Units Recognized by BASS

The many BASS commands require the specification of units (or
combination of units) as part of an option. This section describes
the syntax for units  that are  recognized by BASS'S  input
algorithms. The conversion of user supplied units to  those
actually used by B AS s is accomplished by referencing all units to
the MKS system (i.e., meter, kilogram, second). Tables 8 and 9
summarize prefixes and fundamental units, respectively, that are
recognized by BASS'S unit conversion subroutines. Table 9 also
summarizes the dimensionality and the conversion factor to the
MKS system of each unit. Table 10 summarizes units that are
recognized by B AS s ' s unit conversion subroutines for specifying
ecological, morphometric,  and physiological units.

Units and their prefixes may be specified in either upper or
lower case. If prefixes are used, there must be no embedded
blanks between the prefix and the unit name, e.g., "milligrams"
is correct, "milli grams" is  incorrect. Only those units and their
plural form presented in Tables  9 and  10 are  valid. The
circumflex (A) is used to denote exponentiation (e.g., cm"2 is
presented as cmA-2). The slash (/) is used to denote division. If
multiple slashes are used to specify a unit, they are interpreted
according to strict algebraic logic. For example, both "nig/liter",
and "mg literA-l" are equivalent specifications. Similarly, the
weight specific units  "mg/g/day" are "mg gA-l  dayA-l"  are
equivalent. The unit  conversion  factor (Tables  9  and  10)
converts from the given unit to the MKS system, e.g., 1 calorie
x 2.388x10"'  =1 meter2 kilogram second"2.

4.2.5. Syntax for User Specified Functions

The following syntax rules apply to specifying these options

 •      Brackets   are   used   only   to  delineate units.
        Dimensionless parameters like assimilation efficiency,
        lipid fraction, and Kow must be specified with null units
        The order of  addition  and  multiplication  is  not
        significant. Thus, the following specifications are valid
        and equivalent.
temp(celsius) = 
        temp[celsius] = P sin((f)*t[xMw/te]+(jo) + w7/fc]) = a + P*T[celsius] + y*

      yw«/te]) = a + P*T[celsius] + y*log(W[xunits])
User specified functions do not have to be in reduced
form. For example,  temperature-dependent  power
functions can be specified with a reference temperature
other than 0°Celsius. Thus, BASS will correctly decode
the following functions

so\yunits] = a*exp(p*(T[celsius]-20))*W[xw«/fe]Ay

ln(so\yunits]) = w7/fe](p)) = a + Y*

log(so[yw«/te](P)) =  lp[cm] = 4.5 + 0.0*L[cm]
                                                         41

-------
        pl[-] = 0.05  <=>  pl[-] = 0.05*W[g(FW)]A0.0

•       Operators (A*/+-) may not be  concatenated. For
        example, the following options have invalid syntax

        so[mg(o2)/g/hr]=0.1*exp(0.0693*T[celsius])
                          *W[g(FW)]A-0.2

        ln(so[mg(o2)/g/hr])=-2.30+0.0693*T[celsius]
                                +-0.2*ln(W[g(FW)])

        The correct syntax for these options would be

        so[mg(o2)/g/hr]=0.1*exp(0.0693*T[celsius])
                          *W[g(FW)]A(-0.2)

        ln(so[mg(o2)/g/hr])=-2.30+0.0693*T[celsius]
                                - 0.2*ln(W[g(FW)])

4.2.6. User Supplied Exposure Files

If   the  user  specifies  the  file  option  for  the  /BIOTA,
/TEMPERATURE, /WATER_LEVEL,  or /EXPOSURE commands, the
designated files must exist and be supplied by the user. The
general format of a BASS exposure file allows a user to specify
multiple exposure conditions within  a single file. Each file
record specifies exposure conditions for a specific time The
general format of a BASS exposure file is as follows
        ! file: exposure.dat
        I
        7001
        /Cl
tim&[units]
string
! see ensuing discussion
        /CM    string
        /START_DATA
        VU      V1>2
        V2 1      V2 2
                v1)MV    ! comment
                v2 MV    ! comment
        VNR,1
VNR,2
VNR,NV
                                        ! comment
The records beginning with a slash (/) followed by an integer CJ
identify the  type  of data  (time, exposure  concentration,
temperature, etc.) contained in CJ-th column of each data record.
In this example,  NR is the total number of data records in the
file, NV is the number of variables per record, and C1...CM are
the column positions of  M exposure variables that are to be
read. Note, however,  that MV can be greater than CM and that
C1...CM need not be consecutively numbered. To simplify the
reading of multiple exposure files, BASS requires that "time" be
specified as the first column of any user-supplied exposure file.
Valid character  strings for specifying  the  remaining data
columns include:

cbnths[units](chemical name) to input the concentration of
chemical name in benthic invertebrates;

cinsct[units](chemical name) to input the concentration of
chemical name in incidental terrestrial insects;

cphytn[units](chemical name) to input the concentration of
chemical name in periphyton;

cp])lnk[units](ctiemical name) to input the concentration of
chemical name in phytoplankton;

csdmnt[units](chemical  name)  to  input  the   sediment
concentration of chemical name',

cw&ter[units](chemical name) to input the unbound, aqueous
concentration of chemical name',

czplnk[units](chemical name)  to  input  the whole  body
concentration of chemical name in zooplankton;

benthos[wmYs]  to  input  the standing  stock of benthic
invertebrates;

insects [units] to input the standing stock of incidental terrestrial
insects;

periphyton [units] to input the standing stock of periphyton or
grazable algae;

phytoplankton [units]  to  input  the  standing  stock  of
phytoplankton;

zooplankton [units] to input the standing stock of zooplankton;

temperature[wmYs] to input ambient water temperature.

depth [units] to input water depth.

If column names other than those listed above are specified BASS
simply ignores them.  Data records may  be continued by
appending an ampersand (&) to the line, e.g., the following data
records are equivalent.
                                                    vu
                                                               VI.MV
                                                    'U+i
                                                         Vi,2
                                                         V
                                                           y+2
                                                  Vy&

                                                  Vj,MV
                                                        42

-------
File records must be sequenced such that time is nondecreasing
(i.e., tj < ti+1,  I = 1, 2, ..., N-l). The time increment between
consecutive records can be either constant or variable. BASS
calculates the exposure conditions between specified time points
by simple linear interpolation.
strongly recommended since the graphical interface (GUI) that
is  currently being developed  for BASS uses this  directory
structure. Using the installation procedures outlined in Section
5.1, the BASS installation software INSTBASS.EXE creates the
directory structure below
4.3. Output Files Generated by BASS

Given a user's input BASS generates the following three output
files

•       an  output  file that summarizes  the user's  input
        parameters,  input  errors  detected  by  BASS,  and
        warnings/errors  encountered   during   the   actual
        simulation. This file will have the name of the user' s
        input command file, with  extension "MSG"; e.g.,
        INPUT.DAT will generate the file INPUT.MSG. If the
        file already exists, it will be silently overwritten. See
        Appendix E (page 95) for an example.

•       an output file that tabulates selected results of the
        simulation. Tabulated summaries include 1) annual
        bioenergetic fluxes and growth statistics (i.e., mean
        body weight, mean growth rate) of individual fish by
        species and age class, 2) annualbioaccumulationfluxes
        and statistics (i.e., mean whole body concentrations,
        B AF, and BMP) of individual fish by species and age
        class, and 3) annual community fluxes and statistics
        (i.e., mean population densities andbiomasses) of each
        fish species by age class. This file will have the name
        of the user' s  input command file, with  extension
        "BSS";  e.g., INPUT.DAT will generate  the  file
        INPUT.BSS. If the file already exists, it will be silently
        overwritten. See  Appendix F  (page 112) for an
        example.

•       a Post-script file that contains the plots that were
        requested by the user. The file will have the  name of
        the user'  s input command file, with extension "PLX";
        e.g., INPUT.DAT will generate the file INPUT.PLX.
        If the file already exists, it will be silently overwritten.
        See Appendix G (page 122) for an example.

4.4. Include Files and General File  Management

As mentioned previously BASS enables the user to construct BASS
simulation files using include files. Although the use of include
files was introduced in Section 4.1 as simply a matter of user
convenience, the  installation  software for BASS version 2.1
actually  creates  a  specific  subdirectory structure  to  help
construct and maintain user input files. Although users do not
have to use this subdirectory structure to run BASS, its  use is
C:\BASS  --+-- INSTBASS.EXE
           I
           +-- BASS_V2.EXE
           I
           +-- \DISLIN
           I
           +-- \FISH --  *.FHS
           I
           +-- \COMUNITY --  *.CMM
           I
           +-- \PROPERTY --  *.PRP
           I
           +-- \PROJECTS --+ \projectl  -•
                            I
                            I
                            I
                            I
                            I
                           + \project2
+ *.PRJ
+ *.CHM
+ * . DAT
+ *.BSS
+ *.MSG
+ *.PLX
Files  within the subdirectory  \FISH are all assigned   the
extension FSH.  These  files  specify  the  compositional,
ecological,  morphological, and physiological parameters of a
fish species and are intended to be used as include files for
constructing fish community files which are discussed next. The
general structure of a *.FSH file is

!  file:  name.fsh
!  date:  June  20,  2000
i
!  notes: structure of BASS  fish file
i
/COMMON_NAME   
/SPECIES  
/AGE_CLASS_DURATION 
/SPAWNING_PERIOD 
/FEEDING_OPTIONS allometric(a
-------
                          11[cm]=a*w [g]^b
/PHYSIOLOGICAL_PARAMETERS &
          ge[g/d]=a*w[g]^b*exp(c*t[celsius]);  &
          mf[1/d]=a*w[g]^b*exp(c*t[celsius]);  &
          mi[g/d]=a*w[g]^b*exp(c*t[celsius]);  &
          sg[1/d]=a*w[g]^b*exp(c*t [celsius]);  &
          sm[g]=a*w[g]^b*exp(c*t[celsius]);  &
          so[mg(O2)/h]=a*w[g]^b*exp(c*t[celsius]);  &
          st[min]=a*w[g]^b*exp(c*t[celsius]);  &
          ae_f ish [-] =a;  &
          ae_invert[-]=a; &
          ae_plant[-]=a;  &
          sda: in [-] =a;  &
          rq[-] =a;  &
          rt:std[-] =a
!  end c:\bass\fish\name.fsh

Files within the \COMUNITY subdirectory are all assigned the
extension CMM. These files specify the composition, trophic
structure, and initial conditions of a particular fish community.
These files will  generally  use  FSH  files  from the \FISH
subdirectory as include files and are themselves used as include
files by PROJECTS files. The general form of a *.CMM file is

!  file:c:\bass\comunity\name.cmm
!  date:  June 20,2000

!  notes: structure  of BASS community file

ttinclude 'namel.fsh'
/ECOLOGICAL_PARAMETERS &
       diet (a
/LOG_AC   
/LOG_P    
/LOG_KB1  
/LOG KB2  
/MOLAR_WEIGHT  
/MOLAR_VOLUME  
/MELTING_POINT 
!  end c:\bass\chemical\name.prp

The  PROJECTS directory contains  subdirectories that are
created by the user for a particular model application. In general,
each application should be assigned to its own subdirectory. For
example, the BASS distribution example EVERGLD1.PRJ that
simulates mercury bioaccumulation in  a deep-water Florida
Everglades   community  is  assigned  to  the  subdirectory
C:\B ASS\PROJECTS\EXAMPLE1. Six types of files will reside
in each PROJECTS subdirectory. These file types are: 1) *. PRJ
files that specify the simulation control parameters and chemical
and fish/community include files to be used for this particular
application, 2) *.CHM files that specify chemical exposures and
properties,  3)  *.DAT files which specify actual  chemical
exposures, nonfish standing stocks, water temperature, or water
depth when these functions supplied by the 'file' option,  4)
*.BSS which are the tabular output files  generated by BASS, 5)
*.MSG which are the message output files generated by BASS,
and 6) *.PLX which are the Post Scrip plot files generated by
BASS. The recommended structure of a PRJ file is

!  file:  name.prj
!  date:  June 20, 2000

!  notes: structure of  BASS project  file

/SIMULATION_CONTROL
/HEADER  
/MONTHJTO  
/LENGTH_OF_SIMULATION  [year]
/TEMPERATURE temp[celsius]=
/WATER_LEVEL depth[meter]=
/BIOTA   benthos[g/m*2]=; &
         insects[g/m^2]=; &
         periphyton[g/m^2]=;  &
         phytoplankton[mg/1]=; &
         zooplankton[mg/1]=
/ANNUAL_OUTPUTS  
/SUMMARY_PLOTS pop(length);  cfish(length)

!  specify  chemical properties  and exposures

ttinclude 'namel.chm'

!  specify  fish community

ttinclude 'name2.cmm'
/END

The  chemical exposures and properties  file NAME1.CHM
specified in the preceding project file has the following general
form
                                                       44

-------
!  file: namel.chm
!  date: June 20, 2000

!  notes: structure  of  chemical  exposures
!         and properties  file

!  specify physico-chemical  parameters

ttinclude 1chem_l.prp'
/EXPOSURE cwater[ppm]=;  &
          cbnths[ppm]=;  &
          cinsct[ppm]=;  &
          cphytn[ppm]=;  &
          cpplnk[ppm]=;  &
          czplnk[ppm]=
/LETHALITY    Ic50[units](fish_l)  = a;  ....
/METABOLISM   bt[units](fish_l,chem_n)  = a;

!  repeat above data block as  needed
!  for other chemicals  of concern

!  end namel.chm
The *.FSH, *.CMM, and *.PRP files within the subdirectories
\FISH, \COMUNITY, and \PROPERTY should be considered
by the user to be canonical "databases" for the construction of
new project files. If the user wishes to make changes to any of
these files, the user should either 1) edit the files as desired and
save  the changes as a new *.FSH, *.CMM,  and *.PRP file
within  the   subdirectories  \FISH,   \COMUNITY,   and
\PROPERTY or 2) copy the desired files to a working project
subdirectory. Unless identified with an absolute path, any file
designated by an include command is assumed by default to
specify a path and file name relative to the project file specified
by the command line option "-i" when BASS   is invoked. If a
specified *.FSH, *.CMM, or *.PRP file can not be found in the
subdirectory containing the user's project file, BASS then uses
the extension of the specified file to search the subdirectories
\FISH, \COMUNITY, or \PROPERTY.

4.5.  Command Line Options

To run a BASS simulation which is specified by  an input/project
file INPUT.PRJ, the BASS software is invoked using the UNIX
like command line shown below

        C:\BASS2 I>bass_v21 -iinput.prj
Although the" -i filename" option is the only required command
line option, the following additional options are available

-a=>   print abbreviated tabular output with minimal flux
        summaries
-c =>   print distribution of cpu time in major subroutines
-e =>   integrate by Euler method
-h =>   print this help list and stop (also see -?)
-i filename =>    specify BASS input file (REQUIRED)
-1 =>    turn off lethal effects
-o filename =>   specify BASS_V21 output file
-p =>   print   messages   associated  with  prey
        switching/limitation
-r=>    integrate by Runge-Kutta method (DEFAULT)
-t =>    run test of BASS Runge-Kutta integrator and stop
-? =>   print this help list and stop (also see -h)

For example, the command line

        C:\BASS2I>bass_v21 -iinput.prj -a-c

will  execute the  project  file  INPUT.PRJ and generate
abbreviated summary tables and a distribution of cpu time spent
within various key BASS subroutines.

4.6. Restrictions and Limitations

Commands may be presented in any order with the exceptions
noted below.

•       The /CHEMICAL command must precede the commands
        for any particular chemical since this command defines
        a  new chemical and increments the total number of
        chemicals to be simulated.

•       The /COMMON_NAME command  must  precede  the
        commands for the particular fish, since this command
        essentially  defines a (new) fish.

•       Chemical commands must precede any fish commands.

•       The /END command  must be the last command. Any
        other text or commands following it will be ignored.
                                                      45

-------
              Table 8. Valid Unit Prefixes

Prefix Name              Conversion Factor
    atto                           lO'18
    centi                          10'02
    deca                          10+01
    deci                           lO'01
    exa                           10+18
    femto                         10'15
    giga                           10+09
    hecto                          10+02
    kilo                           10+03
    mega                          10+06
    micro                         lO'06
    milli                          ID'03
    myria                         10+04
    nano                          10'09
    peta                           10+15
    pico                           10'12
    tera                           10+12
                          46

-------
Table 9. Valid Unit Names for Length, Area, Volume, Mass, Time, and Energy. This list is not exhaustive and summaries only
commonly used unit names that BASS'S units conversion program recognizes.

Unit Name
acre
are
btu
calorie
cc
cm
day
decade
erg
fathom
feet
foot
ft
g
gallon
gm
gram
gramme
hectare
hour
hr
imperialgallon
inch
joule
kg
km
1
Ib
liter
litre
m
meter
metre
mg
micron
mile
min
minute
ml
mm
Conversion
Factor
2.471 xlO'04
i.oooxio-02
9.479X10'04
2.388X10'01
1.000xlO+06
1.000xlO+02
1.157X10'05
3.169X10'09
1.000xlO+07
5.468xlO-01
3.281xlO+0°
3.281xlO+0°
3.281xlO+0°
1.000xlO+03
2.642 xlO+02
1.000xlO+03
1.000xlO+03
1.000xlO+03
i.oooxio-04
2.778X10'04
2.778X10'04
2.200 xlO+02
3.937xlO+01
1.000xlO+0°
1.000xlO+0°
i.oooxio-03
1.000xlO+03
2.205 xlO+0°
1.000xlO+03
1.000xlO+03
1.000xlO+0°
1.000xlO+0°
1.000xlO+0°
1.000xlO+06
1.000xlO+06
6.214X10'04
1.667xlO-°2
1.667xlO-°2
1.000xlO+06
1.000xlO+03
Dimensions
Metre
2
2
2
2
3
1
0
0
2
1
1
1
1
0
o
J
0
0
0
2
0
0
3
1
2
0
1
o
J
0
3
3



0


0
0
o
J
1
Kg
0
0
1
1
0
0
0
0
1
0
0
0
0
1
0
1
1
1
0
0
0
0
0
1
1
0
0
1
0
0
0
0
0
1
0
0
0
0
0
0
Second
0
0
-2
-2
0
0
1
1
-2
0
0
0
0
0
0
0
0
0
0
1
1
0
0
-2
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
Description
4840 yards2
100 meter2


cm3


10 years

6 feet


feet, foot
grams
3.785 liter
grams


100 are

hour
4.54 liter


kilograms
kilometer
liter
pound


meter


milligrams
10'6 meter
5280 feet
minute



                                                       47

-------
Table 9. Valid Unit Names (Continuation)
Unit Name
month
nauticalmile
ng
ounce
oz
pint
pound
ppb
ppm
ppq
ppt
quart
s
sec
second
ton
tonne
week
yard
year
Conversion
Factor
3.858X10'07
5.400xlO-°4
1.000xlO+12
3.527xlO+01
3.527xlO+01
2.113xlO+03
2.205 xlO+0°
1.000xlO+06
1.000xlO+03
1.000xlO+12
1.000xlO+09
1.057xlO+03
1.000xlO+0°
1.000xlO+0°
1.000xlO+0°
1.102X10'03
l.OOOxlO'03
1.653 xlO'06
1.094xlO+0°
3.169X10'08
Dimensions
Metre Kg Second
0 0 1
1 0 0
0
0
0
3 (
0
-3
-3
-3
-3
0
0
0
) 0
0
0
0
0
0
300
0 0 1
0 0 1
0 0 1
0 1 0
0 1 0
0 0 1
1 0 0
0 0 1
Description

1852 meter
nanograms

ounce
8 pint = 1 gallon

nanograms/mL
ugrams/mL
femtograms/mL
parts per trillion, picogram/mL
4 quarts = 1 gallon
second
second

2000 pounds
1000 kilograms



                                              48

-------
Table 10. Valid Ecological, Morphometric, and Physiological Unit Names
       Unit Name
       fish
       gram(O2)
       g(02)
       ha
       individuals
       inds
       kcal
       1(02)
       lamellae
       mg(02)
       ml(O2)
       mmole(O2)
       mole(O2)
Conversion
Factor
n.a.
7.370X10'05
7.370X10'05
l.OOOxlO'04
n.a.
n.a.
2.388xlO-°4
5.159X10'05
n.a.
7.370X10'02
5.159xlO-°2
2.303 xlO'03
2.303 xlO'06
Dimensions
Metre Kg Second
000
2 1 -2
2 1 -2
200
000
000
2
2
0 (
2
2
2
2
-2
-2
) 0
-2
-2
-2
-2
Description
treated as  information  as is byte
gram of oxygen
gram of oxygen
hectare
treated as information as is byte
treated as information as is byte
kilocalorie
22.4 liters STP = mole
treated as  information  as is byte
milligram of oxygen = 3.24 calorie
milliliter of oxygen
millimole of oxygen
mole of oxygen
Note:  For purposes  of units conversion,  units used to report oxygen  consumption  are treated dimensionally as joules.
                                                     49

-------
                             5. Software Installation and Management
5.1. MS-DOS Installation

The microcomputer ms-dos BASS 2.1 software is distributed with
1) a readme file, 2) the BASS 2.1 software, and 3) three example
project simulations. The  BASS  2.1 executable and example
simulation files are compressed into a self extracting executable,
INSTBASS.EXE, using PKZIP and must be decompressed
before use. See instructions below.

BASS 2.1 is coded inFortran 95 and its executable, BASSJV21,
has been created using the  Lahey/Fujitsu Fortran 95 5.60
compiler. Although BASS's source  code is not included on its
software distribution diskette, it is  available to any interested
party on request. Please note that there is a bug in the DISLIN
graphics software that BASS uses to generate 3 -dimensional plots
of model results as a function of age or  size class and time. In
particular, there is a bug in DISLIN's hidden line removal
algorithm. This bug has been reported and is being investigated.

INSTBASS.EXE not only installs the BASS 2.1 executable but
also creates a subdirectory structure to  organize and manage
project files  and their associated data  files.  Following  the
instructions givenbelow, INSTBASS.EXE creates the following
subdirectory structure

C:\BASS --+-- INSTBASS.EXE
            I
            +-- BASS_V21.EXE
            I
            +-- \DISLIN
            I
            +-- \FISH  --  *.FHS
            I
            +-- \COMUNITY  --  *.CMM
            I
            +-- \PROPERTY  --  *.PRP
            I
            +-- \PROJECTS  --+ \EXAMPLE1
                              I
                             + \EXAMPLE2
                              I
                             + \EXAMPLE3

The  structure  and use of  the  \FISH,   \COMUNITY,
\PROPERTY, and \PROJECTS subdirectories are described in
Section 4.4 (page 43). The \DISLIN subdirectory contains the
*.DLL file needed to execute the DISLIN graphing software.

Three example BASS projects  are provided in the \PROJECTS
subdirectory. Each example is  allocated its own subdirectory. In
\PROJECTS\EXAMPLE1 the project file EVERGLD1.PRJ
simulates the bioaccumulation of methylmercury in a deep-water
fish community in the Florida Everglades, USA. The major fish
species in these communities are largemouth bass, Florida gar,
yellow bullhead, bluegill and red ear sunfish, and Gambusia.
EVERGLD1.PRJ   uses    the   include   file
\COMUNITY\EVERGLD 1. CMM to specify the ecological and
physiological dataforthese species. The chemical exposures and
properties of methylmercury are provide to EVERGLD1.PRJ
using the include file MERCURY. CHM which in turn uses the
include file \PROPERTY\METYL_HG.PRP. The community's
water depth and the standing stocks of benthos, periphyton, and
zooplankton are specified by NONFISH.DAT. This example is
presented in Section 6 of this user's manual.

In the subdirectory \PROJECTS\EXAMPLE2 the project file
EVERGLD2.PRJ  also simulates  the bioaccumulation  of
methylmercury in a deep-water fish community in the Florida
Everglades, USA dominated by the same fish  species. This
example, however, uses BASS'S "fgets" option to  simulate only
the  growth and  bioaccumulation of  individual fish.  The
community's  population dynamics are not  simulated.  The
ecological and physiological data for this example are provided
by the include file  \COMUNITY\EVERGLD2.CMM.  The
chemical exposures and properties of methylmercury are provide
to EVERGLD2.PRJ using the include file MERCURY.CHM
which   in   turn   uses    the   include   file
\PROPERTY\METYL_HG.PRP. The community's water depth
and the standing stocks of benthos, periphyton, and zooplankton
are  specified by NONFISH.DAT.  These  files,  however, are
simply copies of those found in \PROJECTS\EXAMPLE1.
Because the food web structure and dynamics  specified and
implied by \COMUNITY\EVERGLD2.CMM can not be made
to coincide with that of \COMUNITY\EVERGLD1.CMM, the
output  of  EVERGLD2.PRJ will  not match   that  of
EVERGLD1.PRJ.

In the subdirectory \PROJECTS\EXAMPLE3  the project file
HARTWELL.PRJ simulates the  bioaccumulation  of tetra-,
penta-, hexa-, and hepta-PCB  in a largemouth/sunfish/catfish
community of the Twelve Mile Creek region of Lake Hartwell,
SC, USA which was a USEPA Superfund site. Because the
structure of the Twelve Mile Creek fish community, like many
other largemouth/sunfish/catfish communities throughout the
southeastern US A, closely resembles an Everglades deep-water
community,  the  project  file  HARTWELL.PRJ  uses the
community file \COMUNITY\EVERGLD 1. CMM to model the
community of concern.   This example is intended only to
demonstrate BASS's ability to simulate the bioaccumulation of
arbitrary mixtures and not  what is actually  occurring Lake
Hartwell fish communities. Despite this fact this simulation does
                                                      50

-------
predict some interesting results regarding largemouth bass. In
particular, largemouth bass are predicted to attain internal total
chemical activities on the order of 10% of their expected lethal
chemical activity threshold.  As discussed earlier,  one might
suspect that such accumulations  would begin to  produce
sublethal effects on these fish. Interestingly, biomarker studies
on Twelve Mile Creek largemouth bass indeed suggest this to be
the case.

To install the BASS software the user should first obtain a DOS
prompt and follow the instructions below.

    •   Select a default drive into which the BASS software is
        to be installed (e.g., hard disk "C")

        C:\WINDOWS> CD C:\

    b.   Create a directory for BASS software and then move to
        that directory

        C:\>MKDIRBASS21
        C:\>CDBASS21\

    c.   Request verification of copy results

        C:\BASS21> VERIFY ON

    d.   Transfer the files from the distribution diskette (e.g.,
        drive "A") to the hard disk

        C:\BASS21>COPYA:*.*

    e.   Execute the  installation  file INSTBASS.EXE  to
        recover files from the ZIP archives using the option -d

        C:\BASS21> INSTBASS -d

    f..   Edit your AUTOEXEC.BAT file as follows
        SETBASS=C:\BASS21
        SET PATH=%PATH%;%BASS%
        SET PATH=%P ATH%;%B AS S%\DISLIN

        to execute BASS from any directory and to enable the
        BASS executable to find DISDLL.DLL which is needed
        for DISLIN graphics.

    g.   To run one of the distribution examples move to the
        desired PROJECTS subdirectory and invoke BASS
        using the UNIX like command as shown in the example
        below

        C:\BASS21> CD PROJECTS\EXAMPLE 1
        C:\BASS21\PROJECTS\EXAMPLE1> bass_v21 -i evergldl.prj

5.2. Auxiliary Software

To view and print BASS plot files the user will have to have some
type of PostScript previewing software installed on their system.
If the user does not have any such software, it is recommended
that the user obtain a copy of the Ghostscript/Ghostview/GSview
software.  This freeware  can  be   downloaded  from  the
Ghostscript,   Ghostview  and   Gsview  homepage:
http://www.cs.wisc.cdii/~ghost/.

BASS ' s input files and non-PostScript output files can be viewed
using a wide variety of editors. They can also be viewed using
word processing software such as WordPerfect or Microsoft
Word. When using a word processor, however, the user should
select a non-true type font (e.g., Courier) for viewing so that the
file's intended alignment is display properly. Using a word
processor to view non-PostScript BASS, has the added advantage
being able to compare similar files easily. For example, using
WordPerfect's Document/Compare feature one a easily view any
differences between two BASS output files resulting from a
parameter change.
                                                       51

-------
                                          6. Example Application
Appendix D presents an example BASS project file that simulates
methyl mercury contamination in canals or open water habitats
in the south Florida Everglades. This proj ect file was constructed
as outlined in Section 4.4 (page 43) and is supplied with the
BASS distribution software as \EXAMPLE1. For this application
largemouth  bass  (Micropterus  salmoides),  Florida  gar
(Lepisosteusplatyrhincus), yellow bullheads (Ameiums natalis),
bluegills (Lepomis  macrochirus),  redear  sunfish  (Lepomis
microlophus),  and mosquito  fish(Gambusia holbrooki) are
assumed to be the dominate fish in the habitats of interest and a
generalized food web of such assemblages is depicted in Figure
6.  The  sources  of the  ecological,  morphological, and
physiological parameters used for this example are documented
by comment lines in the files presented in Appendix D. Total
fish biomass in canal and open water Everglades habitats vary
between 150 and 460 kg(FW)/ha (Frank Jordan unpublished
data). Using Jordan's relative abundance data as guidelines, the
initial standing stocks of the bass, gar, bullheads, bluegill, red
ear sunfish, and mosquito fish were assigned to be 20, 10, 20,
200,100, and 10 kg(FW)/ha, respectively, for a total community
biomass of 360 kg(FW)/ha. Based  on Loftus et al. (1998) the
water concentration of methylmercury for the simulation was
assigned to be a constant 0.444 ng/L and the BAF's for benthos
and  zooplankton were  assigned  to  be  10617  and  10599,
respectively.

Appendices  D, E, and  F present  the resulting output files
generated by BASS. At the end of the 10 year simulation the
mean annual standing stocks of the bass, gar, bullheads, bluegill,
red ear sunfish, and mosquito fish are 17.2,12.7,4.51,191,146,
and 0 kg(FW)/ha, respectively, for a total community biomass of
371  kg(Fw)/ha (see  pages  120 and 121). Although the total
elimination of mosquito fish during the simulation may not be
particularly desirable, it is not unrealistic since bass and other
piscivores often exert intense predatory pressures on mosquito
fish and other small fishes in Everglades and other wetland or
swallow water communities.

The simulated whole body concentrations of methyl mercury in
these species agree also well with unpublished data collected by
Ted Lange et al. and Loftus et al. (1998). The annual averaged
concentrations of methylmercury in largemouth, gar, bullhead,
bluegill and red ear weighted by cohort biomasses were 0.817,
0.694,0.539,0.495, and 0.416 mgHg/kg(FW), respectively (see
pages 113, 115, 116, 117, and 118). When weighted by cohort
densities, the annual averaged concentrations of methylmercury
in largemouth, gar, bullhead, bluegill and red ear were 0.671,
0.615, 0.467,0.482, and 0.370 mgHg/kg(FW), respectively (see
pages 113, 115, 116, 117, and 118). Loftus et al. report whole
body  concentrations of methylmercury in largemouth, gar,
bullhead, bluegill and red ear to be 0.967,  1.16, 0.443-0.755,
0.478, and 0.247 mg Hg/kg(FW), respectively.

As is typically observed under field conditions (Forrester et al.
1972; Scott and Armstrong 1972; Cross et al. 1973; Akielaszek
and Haines 1981; Watling et al.  1981; Boush and Thieleke
1983a,1983b;MacCrimmonetal.l983;Ueda and Takeda 1983;
Wren and MacCrimmon 1986; Braune 1987; Luten et al. 1987;
Moharram et  al.  1987; Sprenger et al.1988; Grieb et al. 1990;
Parks et al. 1991; Gutenmann et al.  1992; Lange et al. 1993;
Tracey 1993; Joiris et al. 1995; Munn and Short 1997;  Stafford
and Haines 1997 ),  BASS predicts a strong interdependence
between the body sizes of fish and their mercury whole  body
mercury concentrations. For example, the mean annual mercury
concentration of newly recruited  largemouth whose average
annual body weights is 86.9 g(FW)  is 0.499 mg Hg/kg(FW).
However, the mean annual mercury concentration of oldest
largemouth whose average annual body weights is 1.09 kg(Fw)
is 1.03mgHg/kg(FW).
                                                         52

-------
&
C3

"s
W
-8
 O
,O

.8
 O
O

-------
                                       7. Model Quality Assurance
Quality Assurance (QA) and Quality Control (QC) for the BASS
simulation model has been addressed with respect to:

1)  The model's theoretical foundations, i.e., does the model's
    conceptual  and mathematical framework  standup  to
    scientific/engineering peer view?
2)  The model's implementation, i.e., does the code actually do
    what it is intended to do?
3)  The model's documentation and application, i.e., can the
    model  be used by the outside research  and regulatory
    community  in a meaningful way?

7.1.  Questions  Regarding  QA  of  a  Model's
Scientific Foundations

7.1.1.Is the model's theoretical foundation published in the peer
reviewed literature?

With  the  exception of its  population  and  trophodynamic
algorithms, BASS is based on the FGETS bioaccumulation and
bioenergetics model which has been published in the  peer
reviewed literature (Barber etal. 1988, 1991). The bioenergetic
modeling paradigm employed by BASS  to simulate fish growth
has been used  by  many researchers in the  peer reviewed
literature (Norstrom etal. 1976 ;Kitchell etal. 1977;Mintonand
McLean  1982;  Stewart et al. 1983; Thomann and Connolly
1984;  Cuenco  et al.  1985; Stewart  and Binkowski 1986;
Beauchamp et al. 1989; Barber et al. 1991; Stewart and Ibarra
1991; Lantry and Stewart 1993; Rand et al. 1993; Roell and Orth
1993; Hartman  and Brandt 1995a; Petersen and Ward 1999;
Rose et al.  1999;  Schaeffer et al.  1999). Moreover, since its
construction FGETS has been included in numerous reviews
bioaccumulation models that are applicable for ecological risk
assessments and environmental management decisions (Barren
et al. 1990; Jones et al. 1991; Barnthouse 1992; Chapra and
Boyer 1992; Landrum et al. 1992; Olem et al. 1992; Dixon and
Florian 1993; Cowan et al. 1995; Campfens and Mackay 1997;
Feijtel et al. 1997; Howgate 1998; Wania and Mackay 1999;
Mackay and Fraser 2000; Bartell et al. 2000).

Two criticisms  have  been  lodged against FGETS in  the
literature. The fist of these is that it assumes or attempts to prove
the gill exchange of chemicals is more  important than other
routes of exchange (Madenjian et al. 1993). Madenjian et al.
(1993) took exception to FGETS predictions that "excretion of
PCB through the gills is an important flux in the PCB budget of
lake trout". Madenjian et al. claimed that this  result as  not
supported by any laboratory study on trout and cited Weininger
(1978) as  proof that  gill excretion was  in fact negligible.
Nevertheless  Madenjian  et al.  used a  single,  unidentified
excretion  constant in their model which  simply  lumps all
excretion pathways (i.e.,  gill,  intestinal, urinary, and dermal)
into one. What Madejian et al. are essentially questioning is not
FGETS per se but rather the need to use thermodynamically
based diffusion models for bioaccumulation in general.

The  second criticism is that FGETS is overly complex and
requires too much additional data to parameterize (McKim et al.
1994; Stow and Carpenter 1994; Jackson 1996). Since FGETS's
bioenergetic model for fish growth is not significantly different
from those used by several other authors (Norstrom et al. 1976;
Weininger 1978; Thomann and Connolly 1984; Madenjian et al.
1993; Luk and Brockway 1997) , this criticism is generally
aimed at BASS ' s gill exchange model. As indicated by Tables 2 -
6, however, there is in fact an abundance of gill morphometric
data available to estimate the parameters needed for this model.

7.7.2.  How  has  the  model  or  model  algorithms been
corroborated / validated?

BASS'S bioconcentration and bioaccumulation algorithms have
been validated by comparing its predicted uptake and elimination
rates to published in the peer reviewed literature (Barber et al.
1988; Barber 2000). For  organic chemicals these algorithms
have also been validated by simulations of mixtures of PCBs in
Lake Ontario salmonids and various laboratory studies (Barber
et  al.  1991).   For  sulfhydryl  binding  metals,   BASS'S
bioconcentration algorithms have been validated by simulations
of methylmercury bioaccumulation in Florida Everglades fish
communities one of which is presented herein as a typical BASS
application. For validation of  BASS'S  bioenergetic growth
algorithms the reader should refer to Barber et al. (1991) and the
example herein.

7.1.3. What is the mathematical sensitivity of the model with
respect to parameters, state variables (initial value problems),
and'forcingfunctions/boundary'conditions? What is the model's
sensitivity to structural  changes?

There are four major class of mathematical sensitivity regarding
a model's behavior. These are the model's sensitivity to
parameter changes, forcing functions, initial state variables, and
structural configuration. The first three of these classes generally
are formally defined in term the following partial derivatives
              ££,
               dp,
dX,
3Z.
dX.(Q)
where Jf, is a state variable of interest;/) is some state parameter
                                                        54

-------
of concern; Z, is some external forcing function; andJ^(O) is the
initial value of some state variable of interest which may be Xl
itself.  Structural  sensitivity,  which  generally  cannot  be
formulated as a simple partial derivative, typically concerns the
number and connectivity between the system's state variables.
An excellent question regarding structural sensitivity for a model
like BASS might be how does a predator's population numbers or
growth rate change with the introduction or removal of new or
existing prey items?

Because  model  sensitivity as  defined above  is simply  a
mathematical characteristic of a model, model sensitivity in and
of itself is neither good nor bad. Sensitivity is desirable if the
system being modeled is itself sensitive to the same parameters,
forcing functions, initial state  perturbations, and structural
changes to which the  model  is sensitive. Even though model
sensitivity can contribute to undesirable model uncertainty or
prediction  error, it is important to  acknowledge that  model
sensitivity and uncertainty are not one and the same (Summers
etal. 1993; Wallachand Genard 1998). Model uncertainty, orat
least one of its most common manifestations, is the product of
both the model's sensitivity to particular components and the
statistically variability associated with those components.

A generalized sensitivity analysis of BASS without explicit
specification  of a fish community  of  concern  is undoable.
Furthermore,  the results of a  sensitivity  analysis  for  one
community  generally  cannot  be  extrapolated to  other
communities.  Issues related to BASS'S sensitivity  must  be
evaluated on a case by case basis by the users of the software.
Although procedures for enabling users to conduct a variety of
structured  sensitivity  analyses  are  currently  be developed,
presently the  onus of performing such analyses rests with the
user. Users interested in issues and techniques related  to model
sensitivity and uncertainty should consult the following papers:
Giersch(1991),Elston(1992), Summers etal. (1993),Hakanson
(1995), Norton (1996), Loehle (1997), and Wallachand Genard
(1998).

7.2.  Questions  Regarding  QA   of a  Model's
Implementation

7.2.1. Did the input algorithms properly process all user input?

As part of its routine output BASS generates a *.MSG file which
summarizes all the input data that was used for a particular
simulation. This summary includes not only a line by  line
summary of the user's input commands but also a complete
summary of all control, chemical and fish parameters that BASS
assigned based on the user's specified input file(s). The onus is
then on the user to verify that their input data has been properly
processed.  If not, the user's should report their problem to the
technical contact identified in the BASS user's guide.

BASS has a series of subroutines that check for the completeness
and consistency of the user's input data. When  missing or
inconsistent data is  detected, an appropriate error  message is
written to the above * .MSG file and a error code is set to true. If
this error code  is true after  all the user's input has been
processed, BASS terminates without attempting further program
execution.

7.2.2.  Is the developer reasonably confident that program
subroutines, functions, and procedures are transmitting and
receiving the correct variables? Similarly, is the developer
reasonably confident that program subroutines, functions, and
procedures are not inadvertently changing variable assignments
the shouldn 't be changed?

All BASS subroutines and functions are accessed using implicit
interface  generated by the pertinent Fortran 95 compiler.
Subroutines and functions are packaged together according to
the function and degree of interaction. The BASS version 2.1
software is coded with one main program PROGRAM BASS_v21
(see BASS_v21.F90) and 25 procedure modules. These are

•   MODULE BASS_ALLOC  - subroutines for  allocating and
    reallocating derive type pointers (see BASS_ALLOC.F90).
•   MODULE BASS_CHECK  -  subroutines for checking the
    completeness  and  consistency  of  user  input  (see
    BASS_CHECK.F90).
•   MODULE BAS S_DEFINED - functions for determining whether
    program parameters and variables have been initialized or
    assigned (see BASS_DEFiNED.F90).
•   MODULE BASS_EXP - subroutines for calculating exposure
    conditions (see BASS_EXP.F90).
•   MODULE BASS_INI - subroutines for initialization of program
    variables (see BASS_iNi.F90).
•   MODULE B AS S_INPUT - subroutines for processing user input
    (see BASSJNPUT.F90).
•   MODULE BASS_ODE - subroutines for the computational
    kernel of the BASS software (see BASS_ODE.F90).
•   MODULE BASS_PLOTS - subroutines  for generating BASS
    Output plots (see BASS_PLOTS.F90).
•   MODULE BASS_TABLES - subroutines for generating output
    tables (see BASS_TABLES.F90).
•   MODULE DECODE_FUNCTIONS -  subroutines for decoding
    constant, linear, and power functions from character strings
    (see UTL_DCOD_FNC.F90).
•   MODULE DISLIN_PLOTS - general subroutines for generating
    2 and 3-dimensional DISLIN plots (see UTL_PLOTS.F90).
•   MODULE ERROR_MODULE - subroutines for printing error
    codes  encountered with general utility  modules   (see
    UTL_ERRORS.F90).
                                                         55

-------
•   MODULE FILESTUFF - subroutines for parsing file names and
    obtaining  version   numbers  or  time  stamps   (see
    UTL_FILESTUFF.F90).
•   MODULE FLOATING_POINT_COMPARISONS  - operators  for
    testing equality or  inequality of variables with explicit
    consideration of their computer representation and spacing
    characteristics  (see UTL_FLOATCMP.F90).
•   MODULE GETNUMBERS - subroutines for extracting numbers
    from character strings  (see UTL_GETNUMS.F90).
•   MODULE IOSUBS - subroutines for assigning, opening, and
    closing logical units (see UTL_iosuBS.F90).
•   MODULE MODULO_XFREAD - subroutines for reading files
    which contain  comments, continuation  lines,  and include
    files (see UTL_XFREAD.F90).
•   MODULE MSORT - subroutines for sorting and generating
    permutation   vectors  for  lists  and  vectors    (see
    UTL_MSORT.F90).
•   MODULE MXGETARGS - subroutines for extracting arguments
    from a command line (see UTL_MXGETARGS.F90).
•   MODULE REALLOCATER - subroutines  for allocating and
    reallocating  integer,  logical,  and real pointers (see
    UTL_ALLOC.F90).
•   MODULE SEARCH - subroutines for finding the location of a
    key phase within a sorted list  (see UTL_SEARCH2.F90).
•   MODULE  SEARCH_LISTS  - subroutines for  finding  the
    location  of  a  value  within  a  sorted   list   (see
    UTL_SEARCHl.F90).
•   MODULE  STRFNGS  -  subroutines  for character string
    manipulations  and printing multiline character text (see
    UTL_STRINGS.F90).
•   MODULE TABLEJJTILS  -  subroutines for generating self-
    formating tables (see UTL_PTABLE.F90).
•   MODULE UNITSLIBRARY  - subroutines  for defining and
    performing units conversions  (see UTL_UNITSLIB.F90).

In general these procedure modules are coded with minimal or
no  scoping  units.  Also whenever possible subroutine and
function arguments  are  declared with INTENT(IN)  and
INTENT(OUT)  declarations  to   preclude  unintentional
reassignments.

Although global constants and Fortran parameters are supplied
to program procedures via modules (see question 7.2.3 below),
data exchanges between program procedures are performed via
formal subroutine/function parameters whenever possible. The
only notably exception to this coding policy are modules which
must be used to supply  auxiliary parameters to an "external"
subroutine which is used as an argument to certain mathematical
software packages. Working areas used by BASS are not used for
data transfers between internal or external procedures.

To  simplify the construction and maintenance of the formal
parameter lists of many BASS subroutines and functions and to
help prevent the inadvertent transposition subroutine or function
formal parameters, BASS makes extensive use of derive type data
structures. Each derived type definition is specified within its
own module  and  all derive type  definition  modules  are
maintained in the file BASS_TYPES.F90. A good example of
BASS'S use of derive type data  structures is the derive  type
variable used to store and transfer the ecological, physiological,
and morphometric data for a particular fish species. This derived
type is defined by following module

MODULE dt_fish_par
TYPE:: fish_par
   CHARACTER (LEN=80)  :: ageclass,  class_var,  &
      genus_species, spawning_interval
   INTEGER :: classes=0, spawnings=0
   INTEGER,  DIMENSION(:),  POINTER :: &
      class_model=>NULL(), spawn_dates=>NULL()
   REAL  ::  ae_fish,  ae_invert,  ae_plant,   &
      dry21ive_ab,  dry21ive_aa,  dry21ive_bb,  &
      dry21ive_cc,  gco2_d, la,  longevity, &
      mgo2_s, rbi,  rq, rt2std,  sda2in,  tl_rO, yoy
   REAL, DIMENSIONS)  :: &
      ga,  id, Id,  11,  Ip,  nm,  pa,  pi,  wl
   REAL, DIMENSIONS)  :: ge, mf,  mi, sg,   sm,  so,  st
   REAL, DIMENSION(:), POINTER ::  class_bnds=>NULL()
END TYPE  fish_par
END MODULE dt_fish_par

Many components of this derived type are user input parameters
that have already been discussed. For example, the array ga(2)
stores the coefficient  and exponent of a species'  gill  area
function (see /MORPHOMETRIC_PARAMETERS  page 39). Other
components are secondary parameters that are calculated from
the user's input data. For example, dry21ive_ab, dry21ive_aa,
dry21ive_bb, and dry21ive_cc  are  constants that are used to
calculate  a  fish's live  weight from its dry weight  (see
introduction to Section 2.6. Modeling Growth of Fish). Using a
declaration of the form

    TYPE(fish_par), DIMENSION(nspecies) :: par

all data defined by the above derived type can be passed to a
BASS subroutine by the simple  calling statement

    CALL subl(...., par,....)

without fear of data misalignment.

7.2.3. Is the developer reasonably  confident that all program
subroutines, functions, and procedures are using the same
global constants or parameters?

All global constants are defined within their own individual
                                                        56

-------
modules. These modules include

•  MODULE BASS_CONSTANTS - constants  used by BASS'S
    computational subroutines (see BASS_CONSTANTS.F90).
•  MODULE CONSTANTS - constants used by utility subroutines
    (see UTL_CONSTANTS.F90).
•  MODULE NOVALUE - specifies values for integer, real, and
    character variables that have been been initialized (see
    BASS_CONSTANTS.F90).
•  MODULE SNGL_DBL_QUAD -  specifies the precision  of
    floating point variables as either single, double, or quad
    precision  variables.  This  module  also  assigns certain
    associate   floating   point   constants   (see
    BASS_CONSTANTS.F90).
•  MODULE WORKING_DIMENSIONS - specifies 'standard' sizes
    for  character  variable, input   records,  etc.   (see
    BASS_CONSTANTS.F90).
•  MODULE UNITS_PARAMETERS - specifies parameters used by
    the units conversion subroutines (see UTLJJPARAMS.F90)

7.2.4. Do all strictly mathematical algorithms do what they are
suppose to?  For example   are  root finding  algorithms
functioning properly?

During execution BASS  must employ root finding algorithms for
two important types of calculations. The first of these is the
calculation of a fish's live weight from its dry weight given an
allometric relationship between its live body weight and its
fraction lipid and linear relationships between its percent water,
lipid,   and  non-lipid  organic  matter.  The  second type  of
calculation involves the linear transformation of unconditioned
dietary electivities into self consistent sets of dietary electivities.
These  calculations  are  performed  using  the  combined
bisection/Newton-Raphson algorithm outlined by Press et al.
(1992).

As mentioned earlier,  the BASS software  allows the user to
integrate BASS'S differential equations  using either a simple
Euler method or a fifth-order Runge-Kutta method with adaptive
step sizing. These methods offer the user two distinctly different
options with respect to software performance and execution.
Although Euler methods cannot assess the accuracy of their
integration, such methods often allow for fast model execution.
Runge-Kutta methods, on the other hand,  can monitor the
accuracy of their integration but at the  cost of increased
execution time. This additional computational burden, however,
can often be significantly reduced by employing adaptive step
sizing. BASS'S Runge-Kutta integrator is patterned on the fifth-
order Cash-Karp Runge-Kutta algorithm outlined by Press et. al.
(1992) and was tested using the following system of equations.
           dyjdx = 1.0
           dyjdx = x
           dy3/dx =
           dyjdx = cosh(X)
           dys/dx =
           dy&ldx = 1.07(1.0
    dyjdx = l.U/Vl.U +x^
    dyg/dx= -100(y9-sin(x))
     duldx = 99%u + 1998v
     dvldx= -999 u-1999 v
                                     yg(0) = 1
                                      u(Q) = 1
                                      v(0) = 0
The analytical solution to this system of equations is
   V, =
   y2=
x-x0
0.5(x2-x02)
   y6 =
   y1 =
        - sinh(x0)
 exp(x) - exp(x0)

: arctan(x) - arctan(x0)
: asinh(x) - asinh(x0)
 10101     ,  1AA  ,     100
:	exp(-lOOx)	
 10001               10001
^2exp(-x) -exp(-lOOOx)
= -exp(-x) +exp(-1000x)
                              / N
                           cos(x)
10000
10001
                                                 .  , ,
                                                sm(x)
On the interval [0>5=0.220255E+05. Besides their large
numerical range, the last three equations  in this  system are
numerically stiff (Press et al. 1992; Ascher and Petzold 1998).
When integrated on the  interval [0
-------
therefore step functions of time. All of these features create
points of discontinuity or nondifferentiability. Although there is
nothing intrinsically wrong  with using such formulations in
differential equation models, numerical integrations of such
models  must proceed for  one  point  of  discontinuity /
nondifferentiability to another.

With these considerations in mind, BASS'S computational kernels
(subroutines  BASS_ODESOLVR  and FGETS_ODESOLVR)  are
designed to integrate BASS'S  differential equations for a single
day of the desired simulation period. Immediately following the
call of these computational kernels, BASS calculates the dietary
composition of each fish that will be held constant for that day.
The progress of the subsequent numerical integration within the
day  is then controlled by any conditions that results in a point
of nondifferentiability. The two most important conditions in
this  regard occur when BASS must read an exposure file to
update the parameters for the  linear interpolation of one or more
exposure variables or when one or more cohorts are eliminated
from the community. In the later case, BASS also recalculates the
dietary compositions of the  remaining fish which again will
remain constant for the  remainder of the  day.  Note that
recruitment of new cohorts into the simulated community does
not create a point of nondifferentiability for BASS since such
amendments to the community's structure are performed before
calling  the   computational  kernels  BASS_ODESOLVR  or
FGETS_ODESOLVR   and   therefore  constitutes  a  simple
reinitialization problem.

7.2.6. Are simulated results consistentwith known mathematical
constraint of the model? For example, if state  variable are
suppose to be non-negative, are they? Similarly, if the model is
suppose to mass balance, does it?

BASS'S state variables, like those of most physical or biological
models, must be by definition non-negative. However, insuring
that the numerical integration of a differential equation model
remains constrained to its appropriate state space is not a trivial
issue. Consider, for example, the case when one wants to take a
simple Eulerian step for a non-negative state variable which has
a negative derivative. If the state variable is to  remain non-
negative, then the largest allowable size for the integration step
can be calculated as follows
                 y(t+h) = y(t) + hy'(f)

                      0 < y(f) + hy'(t)
             -y(t)
             y'(t}
> h     where  y!(t) < 0
                                           then an integration  step is possible. If the converse is  true,
                                           however, the function y(f)  is approximating a step function in
                                           which case the desired integration can simply be restarted with
                                           y(t) = 0. There are at least two types of situations that can occur
                                           during a BASS simulations that might necessitate this type of
                                           corrective action. The  first of  these occurs when a cohort
                                           experiences intense predation or other mortality that drives its
                                           population to extinction whereas the second situation might
                                           occur  when there is the  rapid excretion of  a hydrophilic
                                           contaminant  following  the disappearance  of  an aqueous
                                           exposure. Regardless of the integration method used (i.e., Euler
                                           or Runge-Kutta), when the derivative for a fish's body weight,
                                           population density, or body burden is negative, BASS verifies
                                           whether the current integration  step will  in fact yield  non-
                                           negative state values. If not, BASS either executes a simple Euler
                                           step of the appropriate size or restarts the integration with the
                                           appropriate state variables initialized to zero.

                                           When used it its full community mode (i.e., the non-FGETS
                                           option), BASS calculates and reports the mass balance between
                                           the community's total predicted predatory mortality and its total
                                           predicted piscivorous consumption as a mass balance check on
                                           its internal consistency and operation. Forthe example presented
                                           herein this mass balance is -1.953E-02 [g(DW)/ha/yr]. Since this
                                           community's  total piscivory is  calculated to be 2.778E+04
                                           [g(DW)/ha/yr], this mass balance check would have a relative
                                           error of less than 10"6. See page 121.

                                           7.2.7.  Are simulation results consistent across machines or
                                           compilers?

                                           BASS was originally developed on a DEC  3000 work station
                                           using the DEC Fortran 90 compiler.  It has also  been ported to
                                           the Windows operating system on the DELL OptiPlex using the
                                           Lahey/Fujitsu Fortran 95 5.60 compiler. Although the results of
                                           these two implementations to agree with one another up to single
                                           precision accuracy, due to differences in compiler optimization,
                                           model computations must be performed in double precision to
                                           obtain this level of consistency.

                                           7.2.8.  Have  test and reference/benchmark data  sets  been
                                           documented and archived?

                                           At least three different test project files are  maintained to  tract
                                           changes in the  operation  of   BASS associated with  code
                                           maintenance and updates. These files are used as benchmarks to
                                           verify that code modifications that should not change BASS 's
                                           computational results in point of fact do not change BASS'S
                                           simulation output.
If h is greater than the numerical spacing of t (i.e., t + h * t),
                                                          58

-------
7.3.   Questions   Regarding   QA
Documentation and Applications
of   Model
7.3.7. Is the model intended for absolute or comparative
prediction?

Although BASS can be used to analyze results from actual field
studies or predict the expected future condition specific real
communities, its principal intended use is to predict and compare
the outcomes of  alterative  management  options  that  are
associated with pollution control, fisheries management, and/or
ecosystem restoration activities.

7.3.2. Does the User Guide provide the information needed to
appropriate apply and use the model?

The BASS User's Guide summarizes the model's theoretical
foundations and assumptions,  the model's input command
structure, issues related to userfile and project management, and
software installation. The User's Guide  also presents and
discusses the results of one of the three example applications
that are distributed with the BASS software.

7.3.3. What internal checking can be made to help insure that
the model is being used appropriately?
Currently the only internal checking performed by BASS is to
verify that all parameters needed by the model for a particular
simulation have in fact been specified by the user. Although
BASS will assign a few default parameters, most unassigned
parameters are fatal errors. Future versions of BASS will perform
bounds   checking  on  many  of  its  physiological  and
morphological parameters.

7.3.4. Has the developer anticipated computational problem
areas that will cause the model to "bomb "?

Several key mathematical calculations have been identified as
potential problem areas f or a B AS s' s simulation. In general, these
problem areas involve either the unsuccessfully resolution of a
root of a nonlinear equation or the unsuccessfully integration of
BASS'S basic state variables.  Examples of the former include
situations when BASS'S calculated dietary compositions do not
sum to unity or when a fish's live weight is calculated to be less
or equal to its  dry weights. Examples  of the latter include
situations when the current integration  step is  less than the
numerical spacing of the current time point or when  BASS'S
integration error exceeds 10"5. When any of these situations are
encountered,  BASS  terminates  execution  and  issues   an
appropriate error message to the current *.MSG file.
                                                         59

-------
                                        8. Planned Future Features
Presently, ten major program developments  are planned for
BASS. These include:

•   Development of a graphical user interface (GUI) for easy
    construction of input files.

•   Improved plotting capabilities including the generation of
    output files that users can input to their own graphic
    software.

•   Development canonical fish and community databases (i.e.,
    *.FSH and *.CMM files) to facilitate easier application of
    BASS.

•   Software to perform model sensitivity analyses.

•   Implementation of  an option to read  a simulated or
    measured time series of dissolved oxygen concentrations
    that are needed of calculate the fishes' ventilation volumes.
    See Eq.(2-12).  Currently, BASS  uses saturated  dissolved
    oxygen concentrations that are calculated as a function of
    water temperature.

•   Development of submodels  for simulating the biomass
    dynamics  of benthos,  periphyton,  phytoplankton,  and
    zooplankton.

•   Development of submodels for simulating the physiological
    tolerances of fish to water quality parameters other than
    toxic chemicals.

•   Incorporation of quantitative structure activity relationships
    (QSAR's) to predict metabolism of organic chemicals.

•   Development of  migration algorithms for simulating the
    movement of fish into and out of the simulated community
    based on habitat  parameters such as water depth, current
    velocity, availability of prey, etc.

•   Development of subroutines to simulate sublethal, residue-
    based effects.
                                                         60

-------
                                                  References
Abernethy, S.G., D. Mackay, andL.S. McCarty. 1988. "Volume
  fraction" correlationfornarcosis in aquatic organisms: the key
  role of partitioning. Environ. Toxicol. Chem. 7:469-481.

Adey, G., B. Wardley-Smith, and D. White. 1976. Mechanism
  of inhibition of bacterial luciferase by anaesthetics.  Life
  Sciences 17:1849-1854.

Akielaszek, JJ. and T.A. Haines. 1981. Mercury in the muscle
  tissue of fish from three northern Maine lakes. Bull. Environ.
  Contam. Toxicol. 27:201-208.

Ascher, U.M. and L.R. Petzold. 1998. Computer Methods for
  Ordinary Differential Equations and Differential-Algebraic
  Equations. SI AM. Philadelphia, PA pp 314.

Atkins,  P.W. 1978. Physical Chemistry. W.H.  Freeman and
  Company: San Francisco, CA.

Bailey, H.C., J.L. Miller, MJ. Miller, L.C. Wiborg, L. Deanovic,
  and T.  Shed. 1997.  Joint acute  toxicity of  diazinon and
  chlorpyrifos to Ceriodaphnia dubia. Environ. Toxicol. Chem.
  16:2304-2308.

Barber,  M.C. 2000. A  comparison of models for predicting
  chemical bioconcentration in fish. Manuscript for submission
  to Can. J. Fish. Aquat. Sci.

Barber, M.C., L.A. Suarez, and R.R. Lassiter. 1987. "FGETS"
  (Food and Gill Exchange of Toxic Substances): A simulation
  model for predicting the bioaccumulation of nonpolar organic
  pollutants  by fish. U.S. Environmental Protection Agency,
  Office of Research and Development.  EPA/600/3-87/038
  PB88-133558.

Barber, M.C., L.A. Suarez, and R.R. Lassiter. 1988. Modeling
  bioconcentration of nonpolar organic pollutants by fish.
  Environ. Toxicol. Chem. 7:545-558.

Barber, M.C., L.A. Suarez, and R.R. Lassiter. 1991. Modelling
  bioaccumulation of  organic pollutants  in  fish  with an
  application to PCBs in Lake Ontario  salmonids. Can. J. Fish.
  Aquat. Sci. 48:318-337.

Barnthouse, L.W.  1992. The role of models in ecological risk
  assessment:  a 1990's  perspective. Environ. Toxicol. Chem.
  11:1751-1760.

Barron, M.G. 1990. Bioconcentration. Environ.  Sci. Technol.
  24:1612-1618.
Barron,  M.G.,  G.R.  Stehly,  and  W.L.  Hayton.  1990.
  Pharmacokinetic modeling in aquatic animals I. Models and
  concepts. Aquat. Toxicol.  18:61-86.

Bartell, S.M., K.R. Campbell,  C.M. Lovelock, S.K. Nair, and
  J.L. Shaw. 2000. Characterizing aquatic ecological risks from
  pesticides using a diquat dibromide case study III: ecological
  process models. Environ. Toxicol. Chem. 19:1441-1453.

Beamish, F.W.H. 1970. Oxygen consumption of largemouth
  bass, Micropterus salmoides, in relation to swimming speed
  and temperature. Can. J. Zool. 48:1221-1228.

Beamish, F.W.H. 1974. Apparent specific dynamic action of
  largemouth bass, Micropterus salmoides. J. Fish. Res. Bd.
  Canada 31:1763-1769.

Beamish, F.W.H. and P.O. MacMahon. 1988. Apparent heat
  increment and feeding  strategy  in walleye,  Stizostedion
  vitreum vitreum. Aquaculture 68:73-82.

Beamish, F.W.H. and M. Legrow. 1983. Bioenergetics of the
  southern brook lamprey, Ichthyomyzon gagei. J. Anim. Ecol.
  52:575-590.

Beauchamp, D.A., D.J. Stewart,  and G.L. Thomas. 1989.
  Corroboration of a bioenergetics model for sockeye salmon.
  Trans. Am. Fish. Soc. 118:597-607.

Benjakul, S., T.A. Seymour, M.T. Morrissey, andH. An. 1997.
  Physicochemical changes in  Pacific whiting muscle proteins
  during iced storage. J. Food Sci. 62:729-733.

Benoit, J.M., R.P. Mason, and C.C. Gilmore. 1999a. Estimation
  of mercury-sulfide speciation in sediment pore waters using
  octanol-water partitioning and implications for availability to
  methylating bacteria. Environ. Toxicol. Chem. 18:2138-2141.

Benoit, J.M., C.C. Gilmore, R.P. Mason, and A. Heyes.  1999b.
  Sulfide controls on mercury  speciation and bioavailability to
  methylating bacteria in sediment pore waters. Environ. Sci.
  Technol.  33:951-957.

Bergman, E. and L.A. Greenberg. 1994. Competition between a
  planktivore, a benthivore, and a species with ontogenetic diet
  shifts. Ecology 1233-1245.

Boudreau, P.R. and L.M. Dickie. 1989. Biological model of
  fisheries  production based on physiological and ecological
  scalings of body size.  Can. J. Fish. Aquat. Sci. 46:614-623.
                                                        61

-------
Boush, G.M. and J.R.  Thieleke. 1983a. Mercury content in
sharks. Bull. Environ. Contam. Toxicol. 30:284-290.

Boush, G.M. and J.R. Thieleke. 1983b. Total mercury content in
  yellowfin and bigeye tuna. Bull. Environ. Contam. Toxicol.
  30:291-297.

Bozek, M.A., T.M. Burri,  and R.V. Frie.  1999.  Diets  of
  muskellunge in northern Wisconsin lakes. No. Am. J. Fish.
  Manage.  19:258-270.

Branson, D.R., IT.  Takahashi, W.M. Parker, and G.E. Blau.
  1985. Bioconcentrationkinetics of 2,3,7,8 tetrachlorodibenzo-
  p-dioxin in rainbow trout. Environ. Toxicol. Chem. 4:779-788.

Braune, B.M. 1987. Mercury accumulation in relation to size
  and age of Atlantic herring (Clupea harengus harengus) from
  the southwestern  Bay of Fundy,  Canada.  Arch.  Environ.
  Contam. Toxicol.  16:311-320.

Breck, J.E. and M.J. Gitter.  1983. Effect of  fish size on the
  reactive distance of bluegill (Lepomis macrochirus) sunfish.
  Can. J. Fish. Aquat. Sci. 40:162-167.

Brett, J.R. 1971. Satiation time, appetite, and maximum food
  intake of sockeye salmon(Oncorhynchus nerka). J. Fish. Res.
  Bd. Canada 28:409-415.

Brett, J.R.  and  C.A. Zala. 1975. Daily pattern of nitrogen
  excretion  and oxygen  consumption of sockeye salmon
  (Oncorhynchus nerka) under controlled conditions. J. Fish.
  Res. Bd. Canada 32:2479-2486.

Brett, J.R., J.E. Shelbourn, and C.T. Shoop. 1969. Growth rate
  and  body  composition  of  fingerling  sockeye  salmon,
  Oncorhynchus nerka, in relation to temperature and ration
  size. J. Fish. Res. Bd. Canada 26:2363-2394.
Brodeur, R.D. 1991. Ontogenetic variations in the type and size
  of prey consumed by juvenile coho, Oncorhynchus kisutch,
  and chinook, O. tshawytscha, salmon. Environ. Biol. Fishes
  30:303-315.

Bromley, P.J. 1980. The effect of dietary water content and
  feeding rate on the growth and food conversion efficiency of
  turbot (Scophthalmus maximus L.). Aquaculture 20:91-99.

Brown, G.M. 1960. Heat or mass transfer in a fluid in laminar
  flow in a circular or flat conduit. AIChE Journal 6:179-183.

Brown, D.A. and T.R. Parsons. 1978. Relationship between
  cytoplasmic  distribution of mercury and toxic  effects  to
  zooplankton and chum salmon (Oncorhynchus keta) exposed
  to mercury in a controlled ecosystem. J. Fish. Res. Bd. Canada
  35:880-884.

Bruggeman, W.A., L.B.J.M. Martron, D. Kooiman, and  O.
  Hutzinger. 1981. Accumulation and elimination kinetics of di-
  , tri-, and tetra chlorobiphenyls by goldfish after dietary and
  aqueous exposure. Chemosphere 10:811-832.

Burggren,  W.,  J. Dunn,  and  K.  Barnard.  1979.  Branchial
  circulation and gill morphometrics in the sturgeon A cipenser
  transmontanus, an ancient Chondrosteian fish. Can. J. Zool.
  57:2160-2170.

Burnside,  D.F.  1976. Gill surface  area of two species  of
  Fundulus as a function of body  size. Journal of the Elisha
  Mitchell Scientific Society 92:85-86.

Buttkus, H. 1967. Amino acid composition of myosin from trout
  muscle. J. Fish. Res. Bd.  Canada 24:1607-1612.

Buttkus, H.  1971. The sulfhydryl content of rabbit and  trout
  myosin in relation to protein stability. Can. J. Biochem. 49:97-
  107.
Briggs, G.G. 1981. Theoretical and experimental relationships
  between soil adsorption, octanol-water partition coefficients,
  water solubilities, bioconcentration factors, and the parachor.
  J. Agric. Food Chem. 29:1050-1059.

Brink, F. and J.M. Posternak. 1948. Thermodynamic analysis of
  the relative  effectiveness of narcotics. J. Cellular Comp.
  Physiol. 32:211-233.

Broderius, S. and M.  Kahl. 1985. Acute toxicity of organic
  chemical mixtures to the fathead minnow. Aquat. Toxicol.
  6:307-322
Calamari,  D.  and J.S.  Alabaster.  1980.  An approach  to
  theoretical models in evaluating the effects of mixtures of
  toxicants in the aquatic environment. Chemosphere 9: 533-
  538.

Cameron, J.N., J. Kostoris, andP.A. Penhale. 1973. Preliminary
  energy budget of the  ninespine  stickleback  (Pungitius
  pungitius) in an Arctic Lake. J.  Fish. Res. Bd.  Canada
  30:1179-1189

Campbell,  R.D.  and Branson,  B.A.  1978.  Ecology and
  population dynamics of the black bullhead, Ictalurus melas
  (Rafinesque), in central Kentucky. Tulane Studies in Zoology
                                                        62

-------
and Botany 20:99-136.

Campfens, J. and D. Mackay. 1997. Fugacity-based model of
  PCB bioaccumulation in complex food webs. Environ. Sci.
  Technol. 31:577-583.

Carlander, K. 1969. Handbook of Freshwater Fishery Biology,
  Vol. I. Life history data on freshwater fishes of the United
  States and Canada, exclusive of the Perciformes. Iowa State
  University Press: Ames.

Carlander, K. 1977. Handbook of Freshwater Fishery Biology,
  Vol. II. Life history data on Centrarchid fishes of the United
  States and Canada. Iowa State University Press: Ames.

Carlander, K. 1997. Handbook of Freshwater Fishery Biology,
  Vol. III. Life history data on Ichthyopercid and Percid fishes
  of the United States and Canada. Iowa State University Press:
  Ames.

Carreira, L.A., S. Hilal and S.W. Karickhoff,. 1994. Estimation
  of Chemical Reactivity Parameters and Physical Properties of
  Organic Molecules Using  SPARC.  In: P. Politzer and J.S.
  Murray (editors). Theoretical and Computational Chemistry,
  Quantitative  Treatment  of  Solute/Solvent Interactions.
  Elsevier Publishers.

Chapra, S.C. and J.M. Boyer. 1992. Fate of environmental
  pollutants. Water Environ. Res. 64:581-593.

Chiou, C.T., R.L. Malcolm, T.I. Brinton, and D.E. Kile. 1986.
  Water solubility enhancement of some organic pollutants and
  pesticides by dissolved humic and fulvic  acids. Environ. Sci.
  Technol. 20:502-508.

Chung, Y.-C., M.-L. Ho, F.-L., Chyan, and S.-T. Jiang. 2000.
  Utilization of free-dried mackerel (Scomber australasicus)
  muscle proteins as a binder in restructured meat. Fish. Sci.
  66:130-135.
  of  nonspecific toxicity  to  fish using  bioconcentration
  characteristics. Toxicol. Environ. Saf. 24:247-265.

Connell, J.J. andP.F. Howgate. 1959. Studies on the proteins of
  fish skeletal muscle 6. Amino acid composition of cod fibrillar
  proteins. Biochemical Journal 71:83-86.

Connolly, J.P. and C.J.Pedersen. 1988. A thermodynamic-based
  evaluation of organic  chemical  accumulation in aquatic
  organisms. Environ.  Sci. Technol. 22:99-103.

Cowan, C.E., D.J. Versteeg, R.J. Larson, and P. J. Kloepper-
  Sams.  1995.  Integrated  approach  for  environmental
  assessment of new and existing substances. Regul. Toxicol.
  Pharmacol. 21:3-31.

Craig, J.F.  1977. The body composition of the adult perch,
  Perca fluviatilis in Windermere, with reference to seasonal
  changes and reproduction. J. Anim. Ecol. 46:617-632.

Cross, F.A., L.H. Hardy, N.Y. Jones, and R.T. Barber. 1973.
  Relation between total body weight and concentrations of
  manganese, iron, copper, zinc, and mercury in white muscle of
  bluefish (Pomatomus saltatrix) and a bathyl-demersal fish
  Antimora rostrata. J. Fish. Res. Board Can. 30:1287-1291.

Cuenco,  M.L.,  R.R. Stickney, and W.E.  Grant. 1985.  Fish
  bioenergetics  and growth in aquaculture ponds: I. Individual
  fish model development. Ecol. Modi. 27:169-190.

Cui, Y. and R.J. Wootton. 1988. Bioenergetics of growth of a
  cyprinid, Phoxinusphoxinus: the effect of ration, temperature
  and body size on food consumption, faecal production and
  nitrogenous excretion. J. FishBiol. 33:431-443.

Dabrowska, H.,  S.W. Fisher, K. Dabrowska, and A.E. Staubus.
  1996. Dietary uptake efficiency of HCBP in channel catfish:
  the effects of fish contaminantbody burden. Environ. Toxicol.
  Chem.  15:746-749.
Clark, K.E., F.A.P.C. Gobas, and D. Mackay. 1990. Model of
  organic chemical uptake and clearance by fish from food and
  water. Environ. Sci. Technol. 24:1203-1213.

Colton, C.K., K.A. Smith, P. Stroeve, andE.W. Merrill. 1971.
  Laminar flow mass  transfer in a flat duct with permeable
  walls. AIChE Journal 17:773-780.
Damuth, J. 1981. Population density and body size in mammals.
  Nature (London) 290:699-700.

Davis, J.A. and C.E. Boyd. 1978. Concentrations of selected
  elements and ash  in bluegill (Lepomis macrochirus) and
  certain other freshwater fish. Trans. Am. Fish. Soc. 107:862-
  867.
Connell, D.W. 1989. Biomagnificationby aquatic organisms~a
  proposal. Chemosphere 19:1573-1584.

Connell, D. andR. Markwell. 1992. Mechanism and prediction
Dawson, D.A.  1994.  Joint action of carboxyl acid binary
  mixtures on Xenopus embryo development: comparisons of
  joint actions for malformation types. Arch. Environ. Contam.
  Toxicol. 27:243-249.
                                                        63

-------
de  Bruijn,   J.,  W.   Seinen,   and  J.   Hermans.   1993.
  Biotransformation  of  organophoshorus  compounds  by
  rainbow trout (Oncorhynchus mykiss) liver in relation to
  bioconcentration. Environ. Toxicol. Chem. 12:1041-1050.

de Jager, S., M.E. Smit-Onel, JJ. Videler, B.J.M. Van Gils, and
  E.M. Uffink.  1977. The respiratory area of the gills of some
  teleost fishes in relation to their mode of life. Bijdragen tot de
  dierkunde 46:199-205.
Duffy, W.G. 1998. Population dynamics, production, and prey
  consumption of fathead minnows (Pimephales promelas) in
  prairie wetlands: a bioenergetics approach.  Can.  J. Fish.
  Aquat. Sci. 54:15-27.

Dunham, J.B. and G.L. Vinyard. 1997. Relationships between
  body mass, population density, and  the self-thinning rule in
  stream-living   salmonids.   Can.  J.  Fish.  Aquat.  Sci.
  54:1025-1030.
de Wolf, W., J.H.M. de Bruijn, W. Seinen, and J.L.M. Hermens.
  1992. Influence  of biotransformation on the relationship
  between bioconcentration factors and octanol-water partition
  coefficients. Environ. Sci. Technol. 26:1197-1201.
du Preez, H.H. and A. C. Cockroft. 1988a. Nonfaecal and faecal
  losses ofPomadasys commersonni (Teleostei: Pomadasyidae)
  feeding on the surf clam, Donax serra. Comp. Biochem.
  Physiol. 90A:63-70.
Diana, J.S. 1982a. An energy budget for northern pike (Esox
  Indus). Can. J. Zool. 61:1968-1975.

Diana, J.S. 1982b. An experimental analysis of the metabolic
  rate and food utilization of northern pike. Comp. Biochem.
  Physiol. 71A:395-399.

Dixon, K.R. and J.D. Florian, Jr. 1993. Modeling mobility and
  effects of contaminants in wetlands. Environ. Toxicol. Chem.
  12:2281-2292.

Donkin, P., J.  Widdows,  S.V. Evans, C.M. Worrall, and M.
  Carr. 1989. Quantitative structure-activity relationships for the
  effect of hydrophobic organic chemicals on rate of feeding by
  mussels (Mytilus edulis). Aquat. Toxicol. 14:277-294.

Dori, A.M., Z. Lou, E. Holmes, C.-L. J. Li, C.S. Venugopal,
  M.O. James, andK.M. Kleinow. 2000. Effects of micelle fatty
  acid composition and  3,4,3',4'-tetrachlorobiphenyl  (TCB)
  exposure on intestinal  [14C] - TCB  bioavailability and
  biotransformation in channel catfish in  situ preparations.
  Toxicol. Sci. 55:85-96.

Drenner, R.W., W.J. O'Brien, and J.R. Mummert. 1982. Filter-
  feeding rates of gizzard shad. Trans. Am. Fish. Soc. 111:210-
  215.

Driscoll, S.K.  and P.P. Landrum.  1997. A comparison  of
  equilibrium partitioning and critical body residue approaches
  for predicting toxicity of sediment-associated fluoranthene to
  freshwater amphipods.  Environ. Toxicol.  Chem.  16:2179-
  2186.

Dube, S.C.andJ.S.D.Munshi. 1974. Studies on the blood-water
  diffusion barrier of secondary gill lamellae of an air-breathing
  fish,Anabastestudineus (Bloch). Zool. Anz., Jena 193:35-41.
du Preez, H.H. and A. C. Cockroft. 1988b. Nonfaecal andfaecal
  losses of the marine teleost, Lichia amia (Linnaeus, 1758),
  feeding  on live southern mullet, Liza richardsonii (Smith,
  1846). Comp. Biochem. Physiol. 90A:71-77.

Dunbrack,  R.L.  1988.  Feeding of  juvenile coho salmon
  (Oncorhynchuskisutch): maximum appetite, sustained feeding
  rate, appetite return, and body size. Can. J. Fish. Aquat. Sci.
  45:1191-1196.

Dutton, M.D., M. Stephenson, and J.F. Klaverkamp. 1993. A
  mercury saturation assay for measuring metallothionein in
  fish. Environ. Toxicol. Chem. 12:1193-1202.

East, P. andP. Magnan. 1991. Some factors regulatingpiscivory
  of brook trout, Salvelinusfontinalis, in lakes of the Laurentian
  Shield. Can. J. Fish. Aquat. Sci. 48:1735-1743.

Elliott, J.M. 1972. Rates of gastic evacuation in brown trout,
  Salmo trutta L. Freshwat. Biol. 2:1-18.

Elliott, J.M. 1975a. Weight of food and time required to satiate
  brown trout, Salmo trutta L. Freshwat. Biol. 5:51-64.

Elliott, J.M. 1975b. Number of meals inaday, maximum weight
  of food consumed in a day and maximum rate of feeding for
  brown trout, Salmo trutta L. Freshwat. Biol. 5:287-303.

Elliott, J.M. 1976a. Body composition of the brown trout (Salmo
  trutta L.) in relation to temperature and ration size. J. Anim.
  Ecol. 45:273-289.

Elliott, J.M. 1976b. The energetics of feeding, metabolism and
  growth of brown trout (Salmo trutta L.) in relation to body
  weight,  water  temperature and ration size. J. Anim.  Ecol.
  45:923-948.
                                                        64

-------
Elliott, J.M. andL. Persson. 1978. The estimation of daily rates
  of food consumption for fish. J. Anim. Ecol. 47:977-991.

Elrod, J.H. and R. O'Gorman. 1991. Diet of juvenile lake trout
  in southern Lake Ontario in relation to abundance and size of
  prey fishes, 1979-1987. Trans. Am. Fish. Soc. 120:290-302.

El-Shamy, P.M. 1976. Analyses of gastric emptying inbluegill
  (Lepomis macrochirus). J. Fish. Res. Bd. Canada 33:1630-
  1633.

Elston, D.A. 1992.  Sensitivity  analysis in the presence of
  correlated parameter estimates. Ecol. Model. 64:11-22.

Emery, S.H. and A. Szczepanski.  1986. Gill dimensions in
  pelagic elasmobranch fishes. Biol. Bull. 171:441-449.

Erickson, RJ. and J.M. McKim. 1990. A model for exchange of
  organic chemicals at fish gills: flow and diffusion limitations.
  Aquat. Toxicol. 18:175-198.

Eschmeyer, P.H. and A.M. Phillips. 1965. Fat content  of the
  flesh of siscowets and lake trout from Lake Superior. Trans.
  Am. Fish. Soc. 94:62-74.

Evans, D.O. 1984. Temperature independence  of the annual
  cycle of standard metabolism in the pumpkinseed. Trans. Am.
  Fish. Soc.  113:494-512.
  1998. Dietary accumulation and depuration of hydrophobic
  organochlorines:  bioaccumulation  parameters  and  their
  relationship  with the octanol/water  partition  coefficient.
  Environ. Toxicol. Chem. 17:951-961.

Flath, L.E. and J.S. Diana. 1985. Seasonal energy dynamics of
  the alewife in southeastern Lake Michigan. Trans. Am. Fish.
  Soc. 114:328-337.

Forrester, C.R., K.S. Ketchen, and C.C. Wong. 1972. Mercury
  content of spiny dogfish (Squalus acanthias) in the Strait of
  Georgia, British Columbia. J. Fish. Res. Board Can. 29:1487-
  1490.

Franks, N.P.  and  W.R.  Lieb.  1978.  Where do  general
  anaesthetics act? Nature (London) 274:339-342.

Franks, N.P. and W.R. Lieb. 1982. Molecular mechanisms of
  general anaesthesia. Nature (London) 300:487-493.

Franks, N.P. and W.R. Lieb. 1984. Do general anaesthetics act
  by competitive bindingto specific receptors? Nature (London)
  310:599-601.

Friant, S.L. andL. Henry. 1985. Relationship between toxicity
  of certain organic compounds  and their concentrations in
  tissues of aquatic organisms: a perspective.  Chemosphere
  14:1897-1907.
Eyring,  H., J.W. Woodbury,  and J.S.  D'Arrigo.  1973. A
  molecular mechanism of general anesthesia. J. Anesthesiology
  38:415-424.

Feijtel, T., P. Kloepper-Sams, K. denHaan, R. vanEgmond, M.
  Comber, R. Heusel, P.Wierich, W.TenBerge, A. Card, W. de
  Wolf, andH. Niessen. 1997. Integration of bioaccumulation
  in an environmental risk assessment. Chemosphere 34:2337-
  2350.

Ferguson, J.  1939. Use  of chemical potentials  as indices of
  toxicity. Proc. R. Soc. Lond. Ser. B. 127:387-404.

Fernandes, M.N. and F.T. Rantin. 1985. Gill morphometry of
  the teleost Hoplias malabaricus (Bloch). Bol. Fisiol. Anim.
  (Sao Paulo) 9:57-65.

Fernandes, M.N., F.T. Rantin, A.L. Kalinin, and S.E. Moron.
  1994.  Comparative study of gill dimensions of three erythrinid
  species in relation to their respiratory function. Can. J. Zool.
  72:160-165.

Fisk, A.T., R.J. Norstrom, C.D. Cymbalisty, and D.C.G. Muir.
Fulton, C.T. 1977. Two-point boundary value problems with
  eigenvalue parameter contained in the boundary conditions.
  Proc. Royal Soc. Edinburgh 77A:293-308.

Galis, F. and  C.D.N. Barel. 1980. Comparative  functional
  morphology  of the gills of African lacustrine Cichlidae
  (Pisces, Teleostei). Nether. J. Zool. 30:392-430.

Gallagher, M.L., E. Kane, and J. Courtney. 1984. Differences in
  oxygen consumption and ammonia production  among
  American elvers (Anguilla rostrata). Aquaculture 40:183-187.

Garber, K.J. 1983. Effect of fish size, meal size and dietary
  moisture  on gastric  evacuation of pelleted diets  by yellow
  perch, Percaflavescens. Aquaculture 34:41-49.

Garcia, L.M. and I.R.  Adelman. 1985. An in situ estimate of
  daily food consumption and alimentary canal evacuation rates
  of common carp, Cyprinus carpio L. J. FishBiol. 27:487-493.

Garman,  G.C.  and L.A. Nielsen. 1982. Piscivory by stocked
  brown trout (Salmo trutta) and its impact on the nongame fish
  community of Bottom Creek, Virginia. Can. J. Fish. Aquat.
                                                        65

-------
Sci. 39:862-869.
  salmonids in streams. Can. J. Fish. Aquat. Sci. 47:1724-1737.
Gehrke, P.C. 1987.  Cardio-respiratory morphometrics of the
  spangled perch Leiopotherapon  unicolor (Gtinter, 1859),
  (Percoidei, Teraponidae). J. FishBiol. 31:617-623.

Giersch,  C. 1991.  Sensitivity  analysis of ecosystems:  an
  analytical treatment. Ecol. Model. 53:131-146.

Gillen, A.L., R.A. Stein, andR.F. Carline. 1981. Predationby
  pellet-reared  muskelunge  on minnows  and  bluegills  in
  experimental systems. Trans. Am. Fish. Soc. 110:197-209.

Glass, N.R. 1969. Discussion of calculation of power function
  with special reference to respiratory  metabolism in fish.
  J.Fish. Res. Bd. Canada 26:2643-2650.

Gobas,  F.A.P.C.   1993.   A   model  for predicting  the
  bioaccumulation of hydrophobic organic chemicals in food-
  webs: application to Lake Ontario. Ecological Modelling 69:1-
  17.

Gobas,  F.A.P.C. and  D.  Mackay.   1987.  Dynamics  of
  hydrophobic  organic  chemical  bioconcentration  in  fish.
  Environ. Toxicol. Chem. 6:495-504.

Gobas, F.A.P.C., J.R. McCorquodale, and G.D. Haffner. 1993.
  Intestinal absorptionandbiomagnification of organochlorines.
  Environ. Toxicol. Chem. 12:567-576.
Grieb,  T.M., C.T. Driscoll, S.P. Gloss, C.L. Schofield, G.L.
  Bowie, and D.B. Porcella. 1990. Factors affecting mercury
  accumulation in fish in the upper Michigan  peninsula.
  Environ. Toxicol. Chem. 9:919-930.

Grimsrud, L. and A.L. Babb. 1966. Velocity and concentration
  profiles for laminar flow of a Newtonian fluid in a dialyzer.
  Chemical  Engineering Progress,  Symposium Series (66)
  62:19-31.

Grove, D.J., L.G. Loizides, and J. Nott. 1978. Satiation amount,
  frequency  of feeding and gastric  emptying rate  in Salmo
  gairdneri.  J.  FishBiol. 12:507-516.

Groves, T.D.D. 1970. Body composition changes during growth
  in young sockeye (Oncorhynchus  nerka) in fresh water. J.
  Fish. Res. Board Can. 27:929-942.

Gruger, Jr., E.H.,  N.L. Karrick,   A.I. Davidson, and  T.
  Hruby. 1975.  Accumulation of 3,4,3',4'-tetrachlorbiphenyl and
  2,4,5,2',4',5'-hexachlorobiphenyl in juvenile  coho salmon.
  Environ. Sci. Technol. 9:121-127.

Grzenda, A.R., D.F. Paris, and W.J. Taylor. 1970. The uptake,
  metabolism,  and  elimination of  chlorinated residues by
  goldfish (Carassius auratus) fed a 14C-DDT contaminated
  diet.  Trans. Am. Fish. Soc. 99:385-396.
Gobas, F.A.P.C., D.C.G. Muir, andD. Mackay. 1988. Dynamics
  of  dietary bioaccumulation  and  faecal  elimination  of
  hydrophobic  organic  chemicals  in  fish.  Chemosphere
  17:943-962.

Gobas, F.A.P.C.,  A.  Opperhuizen, and O. Hutzinger.  1986.
  Bioconcentration   of  hydrophobic   chemicals   in   fish:
  relationship with membrane permeation. Environ. Toxicol.
  Chem. 5:637-646.

Gordoa, A. and C.M. Duarte. 1992. Size-dependent density of
  the demersal fish off Namibia: patterns within and among
  species.  Can. J. Fish. Aquat. Sci. 49:1990-1993.

Grabner, M. andR. Hofer. 1985. The digestibility of the proteins
  of broad bean (Viciafaba) and soyabean (Glycine max) under
  in vitro conditions simulating the alimentary tracts of rainbow
  trout  (Salmo  gairdneri)  and  carp  (Cyprinus carpio).
  Aquaculture48:lll-122.

Grant, J.W.A.  and D.L. Kramer. 1990. Territory size as a
  predicator of the upper limit to population density of juvenile
Gutenmann, W.H., J.G. Ebel, Jr., H.T. Kuntz, K.S. Yourstone,
  and D.J. Lisk. 1992. Residues of p,p'-DDE and mercury in
  lake  trout as a function of age. Arch. Environ. Contam.
  Toxicol. 22:452-455.

Hakanson, L. 1995. Optimal size of predictive models. Ecol.
  Model. 78:195-204

Hakim,  A.,  J.S.D.  Munshi,  and  G.M.  Hughes.   1978.
  Morphometrics of the respiratory organs of the Indian green
  snake-headed  fish,  Channa punctata.  J.  Zool.,  Lond.
  184:519-543.

Hale, R.S. 1996. Threadfin shad use as supplemental prey in
  reservoir white crappie fisheries inKentucky. No. Am. J. Fish.
  Manage. 16:619-632.

Hambright, K.D. 1991. Experimental analysis of prey selection
  by largemouth bass: role of predator mouth width and prey
  body depth. Trans. Am. Fish. Soc. 120:500-508.

Hamilton, S.J. and P.M. Mehrle. 1986. Metallothionein in fish:
                                                        66

-------
Review of its  importance in assessing stress from metal
contaminants. Trans. Am. Fish. Soc. 115:596-609.

Hamilton, S.J., P.M. Mehrle, and J.R. Jones. 1987a. Cadmium-
  saturation technique for measuring metallothionein in brook
  trout. Trans. Am. Fish. Soc.  116:541-550.

Hamilton, S.J., P.M. Mehrle, and J.R. Jones. 1987b. Evaluation
  of metallothionein measurement as a biological indicator of
  stress from cadmium in brook trout. Trans. Am. Fish. Soc.
  116:551-560.

Hanson,  D. and  K.   Johansen.  1970.  Relationship  of gill
  ventilation and perfusion in Pacific dogfish, Squalus suckleyi.
  J. Fish. Res. Board Can. 27:551-564.

Hanson, J.M. and W.C. Leggett.  1986. Effect of competition
  between two  freshwater fishes on prey consumption and
  abundance. Can. J. Fish. Aquat. Sci. 43:1363-1372.

Hanson, P.C., T.B. Johnson, D.E. Schindler, and J.F. Kitchell.
  1997. Fish bioenergetics 3.0 for Windows.  University of
  Wisconsin, Sea Grant Institute. Madision WI (distributed by
  U.S.  Department   of  Commerce,  National  Technical
  Information Service).

Hartman, K.J. and S.B. Brandt. 1995a. Comparative energetics
  and  development of bioenergetic models for sympatric
  estuarine piscivores. Can. J. Fish. Aquat. Sci. 52:1647-1666.

Hartman,  K.J. and S.B.  Brandt.  1995b. Estimating  energy
  density offish. Trans. Am. Fish. Soc. 124:347-355.

Haydon, D.A., B.M. Hendry,  and S.R. Levinson. 1977.  The
  molecular mechanisms  of  anaesthesia.  Nature  (London)
  268:356-358.

Hayduk,  W.  and  H.   Laudie.   1974. Prediction of  diffusion
  coefficients for nonelectrolytes in dilute aqueous solutions.
  AIChE Journal 20:611-615.

Hermanutz, R.O., J.G. Eaton, and L.H. Muller. 1985. Toxicity
  of endrin and malathion mixtures to  flagfish  (Jordanella
  floridae). Arch. Environ. Contam. Toxicol. 14:307-314.

Hermens, J. andP. Leeuwangh. 1982. Joint toxicity of mixtures
  of 8 and 24 chemicals to the guppy (Poecilia reticulata).
  Ecotoxicol. Environ. Saf. 6:302-310.

Hermens, J., P. Leeuwangh, and A. Musch. 1985c. Joint toxicity
  of mixtures of groups of organic aquatic pollutants to the
  guppy (Poecilia reticulata). Ecotoxicol. Environ. Saf. 9:321-
  326.
Hermens,  J.,  E. Broekhuyzen, H. Canton, and R. Wegman.
  1985a.  Quantitative  structure activity  relationships  and
  mixture toxicity studies of alcohols and chlorohydrocarbons:
  effects on growthof Daphnia magna. Aquat. Toxicol. 6:209-
  217.

Hermens,  J., H. Canton, P. Janssen, and R. de Jong. 1984a.
  Quantitative  structure-activity relationships  and  toxicity
  studies of mixtures of chemicals with anaesthetic potency:
  acute lethal and sublethal toxicity to Daphnia magna. Aquat.
  Toxicol. 5:143-154.

Hermens,  J., H. Canton, N. Steyger, and R. Wegman. 1984b.
  Joint effects of a mixture of 14 chemicals on mortality and
  inhibition of reproduction of Daphnia magna. Aquat. Toxicol.
  5:315-322.

Hermens,  J.,  H. Konemann, P. Leeuwangh, and A. Musch.
  1985b. Quantitative structure-activity relationships in aquatic
  toxicity studies of chemicals and  complex  mixtures of
  chemicals. Environ. Toxicol. Chem. 4:273-279.

Hills, B.A. and G.M. Hughes.  1970. A dimensional analysis of
  oxygen transfer in fish gills. Respir. Physiol. 9:126-140.

Holling, C.S. 1966. The functional response of invertebrate
  predators to prey density. Memoirs of the Entomological
  Society  of Canada 48:1-86.

Howgate,  P.  1998. Review of the public health safety of
  products from aquaculture. Int. J.  Food Sci. Technol. 33:99-
  125.

Hughes, G.M. 1966. The dimensions offish gills in relation to
  their function. J. Exp. Biol. 45:177-195.

Hughes,  G.M.  1972.  Morphometrics of fish  gills. Respir.
  Physiol. 14:1-25.

Hughes, G.M. 1978. On the respiration of Torpedo marmorata.
  J. Exp. Biol. 73:85-105.

Hughes, G.M. 1984. General anatomy of the gills. In: W.S. Hoar
  and D.J. Randall (eds). Fish Physiology, Vol XA. Academic
  Press, New York.

Hughes, G.M. 1995. Preliminary morphometric study of the gills
  of Orechromis alcalicus grahami from Lake Magadi and a
  comparison with O. niloticus. J. Fish Biol. 47:1102-1105.
                                                         67

-------
Hughes, G.M. andN.K. Al-Kadhomiy. 1986. Gill morphometry
  of the mudskipper, Boleophthalmus boddarti. J. Mar. Biol.
  Ass. U.K. 66:671-682.

Hughes,  G.M.  and  I.E.  Gray.  1972.  Dimensions   and
  ultrastructure of toadfish gills. Biol. Bull. 143:150-161.

Hughes, G.M. andM. Morgan. 1973. The structure of fish gills
  in relation to their respiratory function. Biol. Rev. 48:419-475.

Hughes, G.M. and S.-I. Umezawa. 1983. Gill structure of the
  yellowtail andfrogfish. Japan. J. Ichthyol. 30.176-183.

Hughes, G.M., S.C. Dube, and J.S.D. Munshi. 1973. Surface
  area of the respiratory organs of the climbing perch, Anabas
  testudineus  (Pisces:   Anabantidae).  J.   Zool.,  Lond.
  170:227-243.

Hughes, G.M., S.F. Perry, and J. Piiper. 1986. Morphometry of
  the gills of the elasmob ranch Scyliorhinus stellar is in relation
  to body size. J. Exp. Biol. 121:27-42.

Itano, K. and k. Sasaki. 1983. Binding of mercury compounds to
  protein components of fishmuscle. Bull. Japan. Soc. Sci. Fish.
  49:1849-1853.

Itoh, Y., R. Yoshinaka, and S. Ikeda. 1979. Effects of sulfhydryl
  reagents on the gel formation of carp actomyosin by heating.
  Bull. Japan. Soc. Sci. Fish. 45:1023-1025.

Jackson, L. 1996. A simulation model of PCB dynamics in the
  Lake Ontario pelagic food web. Ecol. Model. 93:43-56.

Jakubowski, M. 1982. Size and vascularization of the gill  and
  skin   respiratory   surfaces   in   the   white   amur,
  Ctenopharyngodon idella (Val.) (Pisces, Cyprinidae). Acta
  Biol. Cracov. Ser.  Zool. 24:93-106.
  of rainbow trout (Oncorhynchus mykiss). Environ. Toxicol.
  Chem. 14:1847-1858.

Janoff, A.S., M.J. Pringle, andK.W. Miller. 1981. Correlation
  of general anesthetic potency with solubility in membranes.
  Biochim. Biophys. Acta 649:125-128.

Jensen,  A.L.  1986.  Functional  regression  and correlation
  analysis. Can. J. Fish. Aquat. Sci. 43:1742-1745.

Jensen, A.L., S.A. Spigarelli, andM.M. Thommes. 1982. PCB
  uptake by five species of fish in Lake Michigan, Green Bay of
  Lake Michigan, and Cayuga Lake, New York. Can. J. Fish.
  Aquat. Sci. 39:700-709.

Jobling, M. 1981. Mathematical models of gastric emptying and
  the estimation of daily rates of food consumption for fish. J.
  Fish Biol. 19:245-257.

Jobling, M.  1986. Mythical  models of gastric emptying and
  implications for food  consumption studies. Environ. Biol.
  Fishes 16:35-50.

Jobling, M. 1987. Influence of particle size and dietary energy
  content on patterns of gastric evacuation in fishes: test of a
  physiological model  of gastric  emptying. J.  Fish Biol.
  30:299-314.

Johnson, B.L., D.L. Smith, and R.F. Carline. 1988. Habitat
  preferences, survival, growth, foods, and harvests of walleye
  and walleye x sauger hybrids. N. Am. J. Fish. Manage. 8:292-
  304.

Jones, K.C., T. Keating, P.  Diage, and A.C. Chang.  1991.
  Transport and food chain modeling and its role in assessing
  human exposure to organic chemicals. J.  Environ.  Qual.
  20:317-329.
Jakubowski, M.  1992.  Reexamination of the gill respiratory
  surface area in the pike, Esox lucius, and remarks on several
  other fish species . Acta Biol. Cracov. Ser. Zool. 34: 25-32.

Jakubowski, M. 1993. Morphometry of the gill respiratory area
  in Comephorus dyoowskii and some other endemic Cottoidei
  of Lake Baikal. Acta Zool., Stockholm 74:283-288.

Jakubowski, M., L.  Halama,  and  K.  Zuwala.  1995. Gill
  respiratory  area  in the  pelagic sculpins of Lake  Baikal,
  Cottocomephorus inermis and C. grewingki (Cottidae). Acta
  Zool., Stockholm 76:167-170.
Jordan,  F., Haney,  D.C.,  and Nordlie,  F.G. 1993. Plasma
  osmotic regulation and  routine metabolism in the Eustis
  pupfish,   Cyprinodon  variegatus  hubbsi   (Teleostei:
  Cyprinodontidae). Copeia 1993:784-789.

Johnson, P.C. and G.L. Vinyard. 1987. Filter-feeding behavior
  and particle retention  efficiency of Sacramento Blackfish.
  Trans. Am. Fish. Soc. 116:634-640.

Joiris, C.R., I.E. Ali, L. Holsbeck, M. Bossicart, and G. Tapia.
  1995. Total and organic mercury in Barents Sea pelagic fish.
  Bull. Environ. Contam. Toxicol. 55:674-681.
Janes, N. andR.C. Playle. 1995. Modeling silver binding to gills    Juanes, F. 1986. Population density and body size in birds. Am.
                                                         68

-------
Nat. 128:921-929.

Juanes,  F.  1994. What determines prey size selectivity in
  piscivorous fishes? In: DJ. Stouder, K.L. Fresh, and RJ.
  Feller  (editors);  M.  Duke  (assistant editor). Theory and
  Application in Fish Feeding Ecology. University of South
  Carolina Press. p:79-100.

Juanes, F., R.E. Marks, K.A. McKown, and D.O. Conover.
  1993. Predation by  age-0 bluefish on age-0 anadraomous
  fishes in the Hudson River estuary. Trans. Am. Fish. Soc.
  122:348-356.

Jude, D.J., F.J. Tesar,  S.F. Deboe, and T.J. Miller. 1987. Diet
  and selection  of major  prey  species by Lake Michigan
  salmonines, 1973-1982. Trans. Am. Fish. Soc. 116:677-691.
Kobayashi, H, O. Murata, and T. Harada. 1988. Some aspects of
  gill measurement in relation to the growth of the yellowtail
  Seriola quinqueradiata. Nippon Suisan Gakkaishi 54:49-54.

Konemann,   H.   1981a.   Quantitative   structure-activity
  relationships in fish toxicity studies. Part 1: Relationship for
  50 industrial pollutants. Toxicology 19:209-221.

Konemann, H. 198 Ib. Fish toxicity tests with mixtures of more
  than two chemicals: a proposal for a quantitative approach and
  experimental results. Toxicology 19:229-238.

Kunisaki, N., K. Takada, and H. Matsuura. 1986. On the study
  of lipid content, muscle hardness, and fatty acid composition
  of wild and cultured horse mackerel. Nippon Suisan Gakkaishi
  52:333-336.
Karickhoff, S.W. 1981. Semi-empirical estimation of sorption of
  hydrophobic  pollutants on natural  sediments and soil.
  Chemosphere 10:833-846.

Keeley,  E.R.  and  J.W.A.   Grant.  1995.  Allometric  and
  environmental correlates of territory size in juvenile Atlantic
  salmon (Salmo saler). Can. J. Fish. Aquat. Sci. 52:186-196.

Kisia,  S.M.  and G.M. Hughes. 1992. Estimation of oxygen
  diffusing capacity in the gills of different sizes  of a tilapia,
  Orecromis niloticus. J. Zool., London 227:405-415.

Kitchell, J.F.,DJ. Stewart, andD. Weininger. 1977. Application
  of a bioenergetics models to yellow perch (Percaflavescens)
  and  walleye (Stizostedion  vitreum  vitreum). J. Fish. Res.
  Board Can. 34:1922-1935.

Klaverkamp, J.F. and D.A.  Duncan.  1987. Acclimation to
  cadmium toxicity by white suckers: cadmiumbinding capacity
  and  metal distribution in  gill  and liver  cytosol. Environ.
  Toxicol. Chem. 6:275-289.

Kleeman, J.M., J.R.  Olson,  S.M. Chen, and R.E. Peterson.
  1986a.  Metabolism  and  deposition  of  2,3,7,8-
  tetrachlorodibenzo-p-dioxin in rainbow trout. Toxicol. Appl.
  Pharmacol. 83:391-401.

Kleeman, J.M., J.R.  Olson,  S.M. Chen, and R.E. Peterson.
  1986b.   Metabolism  and  deposition  of  2,3,7,8-
  tetrachlorodibenzo-p-dioxin in yellow perch. Toxicol. Appl.
  Pharmacol. 83:402-411.

Knight, R.L., F.J. Margraf, andR.F. Carline. 1984. Piscivoryby
  walleyes and yellow perch in western Lake Erie. Trans. Am.
  Fish. Soc. 113:677-693.
Kushlan, J.A., S.A. Voorhees, W.F. Loftus, andP.C. Frohring.
  1986. Length, mass, and calorific relationships of Everglades
  animals. Fla. Sci. 49:65-79.

Kutty,M.N. 1968. Respiratory quotients in goldfish and rainbow
  trout. J. Fish. Res. Bd. Canada 25:1689-1728.

Lacasse, S.  and  P. Magnan.  1992. Biotic  and  abiotic
  determinants of the diet of brook trout, Salvelinusfontinalis,
  in lakes of the Laurentian Shield. Can.  J. Fish. Aquat. Sci.
  49:1001-1009.

Lammens, E.H.R.R., H.W. de Nie,  and J. Vijverberg. 1985.
  Resource partitioning and niche  shifts  of bream (Abramis
  bramd) and eel (Anguilla anguilla) mediated by predation of
  smelt (Osmerus eperlanus) onDaphnia hyalina. Can. J. Fish.
  Aquat. Sci. 42:1342-1351.

Landolt, J.C. and L.G. Hill.  1975. Observations on the gross
  structure and dimensions of the gills of three species of gars
  (Lepisosteidae). Coepia 1975:470-475.

Landrum, P.P., H. Lee, II, andM.J. Lydy. 1992. Toxicokinetics
  in aquatic systems: model comparisons and  use  in hazard
  assessment. Environ. Toxicol. Chem. 11:1709-1725.

Lange, T.R., H.E. Royals, andL.L. Connor. 1993. Influence of
  water chemistry on mercury concentration in largemouthbass
  from Florida lakes. Trans. Am. Fish. Soc. 122:74-84.

Lantry, B.F. and DJ. Stewart. 1993. Ecological energetics of
  rainbow smelt in the Laurentian Great  Lakes: an interlake
  comparison. Trans. Am. Fish. Soc. 122:951-976.

Lassiter, R.R. 1990. A theoretical basis for predicting sublethal
                                                         69

-------
effects of toxic chemicals.  U.S.  Environmental Protection
Agency, Office of Research and Development. Internal Report
September 1990.

Lassiter, R.R. and T.G. Hallam.  1990. Survival of the fattest:
  implications for  acute effects of lipophilic chemicals on
  aquatic populations. Environ. Toxicol. Chem. 9:585-595.

Lassiter, R.R. andD.K. Kearns. 1974. Phytoplankton population
  changes and nutrient flucuations in a simple ecosystem model.
  In  Modeling  the   Eutrophication   Process.  In:   EJ.
  Middlebrooks, D.H. Falkenborg, and T.E. Maloney (editors).
  Ann Arbor Sci. Publ., Ann Arbor, MI. pp. 131-138.

Law, R.H., A. Mellors, and F.R. Hallet. 1985. Physical aspects
  of inhibition of enzymes by hydrocarbons: Inhibition of a-
  chymotrypsinby chlorinated aromatics and alkanes. Environ.
  Res. 36:193-205.

Lewis, S.V.  and I.C. Potter. 1976.  Gill morphometrics of the
  lampreys Lampetra fluviatilis (L.) and Lampetra  planeri
  (Bloch). ActaZool. Stockh. 57:103-112.

Lewis, W.M., R. Heidinger, W. Kirk, W. Chapman, and D.
  Johnson.  1974. Food intake of the largemouth bass. Trans.
  Am. Fish.  Soc. 103:277-280.

Lieb, A.J., D.D. Bills, andR.O. Sinnhuber. 1974. Accumulation
  of dietary  polychlorinated  biphenyls  (Aroclor  1254) by
  rainbow trout (Salmo gairdneri). J.  Agric.  Food Chem.
  22:638-642.
Loehle, C. 1997. A hypothesis testing framework for evaluating
  ecosystem model performance. Ecol. Model. 97:153-165

Lockhart,  W.L., J.F.  Uthe,  A.R. Kenney, and P.M. Mehrle.
  1972.   Methylmercury  in  northern  pike  (Esox  lucus):
  Distribution,  elimination,   and  some  biochemical
  characteristics of contaminated fish. J. Fish. Res. Bd. Canada
  29:1519-1523.

Loftus, W.F., J.C.  Trexler,  and R.D. Jones. 1998. Mercury
  transfer through  an Everglades aquatic food web.  Florida
  Department  of  Environmental  Protection.  Final  Report
  Contract SP-329.

Lorenzen, K. 1996. The relationship between body weight and
  natural mortality  in juvenile and adult fish: a comparison of
  natural ecosystems and aquaculture. J. FishBiol. 49:627-647.

Low, W.P., Y.K. Ip,  and D.J.W. Lane. 1990. A comparative
  study   of  the  gill  morphometry  in  the  mudskippers-
  Periophthalmus chrysospilos, Boleophthalmus boddaeti and
  Periophthalmodon schlosseri. Zool. Sci. 7:29-38.

Lowe, T.P., T.W. May, W.G. Brumbaugh, andD.A. Kane. 1985.
  National Contaminant Bio monitoring Program: concentrations
  of seven elements in freshwater fish, 1979-1981. Arch.
  Environ. Contam. Toxicol. 14:363-388

Luk,  O.K.  and  F.  Brockway.  1997.   Application of a
  polychlorinated biphenyls bioaccumulation model to Lake
  Ontario lake trout. Ecol. Model. 101:97-111..
Lien,  G.J. and J.M. McKim. 1993. Predicting branchial and
  cutaneous uptake of 2,2',5,5'-tetrachlorbiphenyl in fathead
  minnows  (Pimephales  promelas) and Japanese  medaka
  (Oryzias latipes)'. Rate limiting factors. Aquat. Toxicol. 27:15-
  32.
Luten, J.B., W. Bouquet, G. Riekwel-Booy, A.B. Rauchbaar,
  and M.W.M. Scholte. 1987. Mercury in flounder, Platichtys
  flesus, cod, Gadus morhua, and perch, Perca fluviatilis, in
  relation to  their length  and environment.  Bull.  Environ.
  Contam. Toxicol. 38:318-323.
Lien, G.J., J.W. Nichols, J.M. McKim, and C.A. Gallinat. 1994.
  Modeling the accumulation of three waterborne chlorinated
  ethanes  in fathead  minnows (Pimephales promelas)'.  A
  physiologically based  approach. Environ. Toxicol.  Chem.
  13:1195-1205.
MacCrimmon, H.R., C.D. Wren, andB.L. Gots. 1983. Mercury
  uptake by lake trout, Salvelinus namaycush, relative to age,
  growth, and diet in Tadenac Lake with comparative data from
  other PreCambrian Shield  lakes. Can. J. Fish. Aquat. Sci.
  40:114-120.
Lin, T.M. and J.W. Park. 1998. Solubility of salmon myosin as
  affected by conformational changes at various ionic strengths
  andpH. J. Food Sci. 63:215-218.

Liszka, E. 1969. The vascularization and respiratory surface of
  gills in the  river  bullhead (Coitus gobio L.).  Acta Biol.
  Cracov. Ser. Zool. 12:135-149.
Mackay,  D. 1982. Correlation  of bioconcentration  factors.
  Environ. Sci. Technol. 16:274-278.

Mackay, D. and A. Fraser. 2000. Bioaccumulation of persistent
  organic chemicals: mechanisms and models. Environ. Pollut.
  110:375-391.

Mackay, D. and A.I. Hughes. 1984. Three-parameter equation
                                                        70

-------
describing the uptake of organic compounds by fish. Environ.
Sci. Technol. 18:430-444.

MacRae, R.K., D.E. Smith, N. Swoboda-Colberg, J.S. Meyer,
  andH.L. Bergman. 1999. Copper binding affinity of rainbow
  trout (Oncorhynchus mykiss) and brook trout  (Salvelinus
  fontinalis) gills: implications for assessingbioavailable metal.
  Environ. Toxicol. Chem. 18:1180-1189.
Matthiessen, P., G.F. Whale, RJ. Rycroft, and D.A. Sheahan.
  1988. The joint toxicity of tank-mixes to rainbow trout. Aquat.
  Toxicol. 13:61-76.

Mattingly, H.T. andMJ. Butler, IV. 1994. Laboratory predation
  on the Trinidadian guppy:  implications for  size-selective
  predation hypothesis and guppy life history evolution. Oikos
  69:54-64.
Madenjian, C.P., S.R. Carpenter, G.E. Eck, and M.A. Miller.
  1993. Accumulation of PCBs  by lake trout  (Salvelinus
  namaycush): An individual-based model approach. Can. J.
  Fish. Aquat. Sci. 50:97-109.

Madenjian, C.P.,  T.J. DeSorcie, and R.M. Stedman.  1998.
  Ontogenic and spatial patterns in diet and growth of lake trout
  in Lake Michigan. Trans. Am. Fish. Soc. 127:236-252.

Madon, S.P. and D.C. Culver. 1993. Bioenergetics model for
  larval and  juvenile walleyes:  an in  situ approach with
  experimental ponds. Trans. Am. Fish. Soc. 122:797-813.

Magnan, P. 1988. Interactions between brook charr, Salvelinus
  fontinalis,  and  nonsalmonid  species:  ecological  shift,
  morphological  shift,  and their impact  on zooplankton
  communities. Can. J. Fish. Aquat. Sci. 45:999-1009.

Maina, J.N. and G.M.O. Maloiy. 1986. The morphology of the
  respiratory organs of the African air-breathing catfish (Clarias
  mossambicus): A light, electron and scanning microscopic
  study, with morphometric observations.  J. Zool.,  Lond.
  209:421-445.

Major, M.A., D.H. Rosenblatt, and K.A. Bostian.  1991. The
  octanol/water partition coefficient of methylmercury chloride
  and methylmercury hydroxide in pure water and salt solutions.
  Environ. Toxicol. Chem. 10:5-8.

Marais, J.F.K. andT. Erasmus. 1977. Chemical composition of
  the alimentary canal contents of mullet (Teleostei: Mugilidae)
  caught in the Swartkops Estuary near Port Elizabeth, South
  Africa. Aquaculture 10:263-273.

Margenau,  T.L., P.W. Rasmussen, and  J.M. Kampa.  1998.
  Factors affecting growth of northern pike in small Wisconsin
  lakes. No. Am. J. Fish. Manage. 18:625-639.

Mason, A.Z. and K.D. Jenkins. 1995. Metal detoxification in
  aquatic organisms.  In: A. Tessier and D.R. Turner (editors).
  Metal Speciation and  Bioavailability  in  Aquatic Systems.
  IUPAC  Series  on Analytical and Physical Chemistry  of
  Environmental Systems. John Wiley & Sons, pp 479-608.
Mazon, A. de F.,  M.N. Fernandes, M.A.  Nolasco,  and W.
  Severi. 1998. Functional morphology of gills and respiratory
  areas of two active rheophilic fish  species,  Plagioscion
  squamosissimus  and Prochilodus  scrofa.  J.  Fish Biol.
  52:50-61

McCarty, L.S. 1986. The relationship between aquatic toxicity
  QSARs and bioconcentration for some organic chemicals.
  Environ. Toxicol. Chem. 5:1071-1080.

McCarty,   L.S.    and  D.   Mackay.   1993.   Enhancing
  ecotoxicological  modeling and assessment. Environ. Sci.
  Technol. 27:1719-1728.

McCarty, L.S., P.V. Hodson, G.C. Craig, and K.L.E. Kaiser.
  1985. The use of quantitative structure-activity relationships
  to predict the acute and chronic toxicities of organic chemicals
  to fish. Environ. Toxicol. Chem. 4:595-606.

McGurk,M.D. 1993. Allometry of herring mortality. Trans. Am.
  Fish. Soc.  122:1035-1042.

McGurk, M.D. 1999. Size dependence of natural mortality rate
  of sockeye salmon and kokanee in freshwater. No.  Am. J.
  Fish. Manage. 19:376-396.

McKim. J.M., J.W. Nichols, G.J. Lien, and S.L. Bertelsen. 1994.
  Respiratory-cardiovascular physiology and chloroethane gill
  flux in the channel catfish, Ictalurus punctatus.  J. Fish Biol.
  44:527-547.

Meyer,  H.  1899.  Zur  theorie  der  Alkoholnarkose, Erste
  Mittheilung. Welche Eigenschaft der Anasthetica bedingt ihre
  narkotishe Wirkung? Arch. Exp. Pathol. Pharmakol. 42:109-
  118.

Middleton, A.J. andE.B. Smith. 1976. General anaesthetics and
  bacterial luminescence II. The effect of diethyl ether on the in
  vitro light emission of Vibrio fischeri. Proc. R. Soc. Lond. Ser.
  B 193:173-190.

Miller, K.W., W.B.M. Paton, R.A.  Smith, andE.B.  Smith. 1973.
  The pressure reversal of anesthesia and the critical volume
                                                        71

-------
hypothesis. Mol. Pharmacol. 9:131-143.

Miller, T.J., L.B. Crowder, J.A. Rice, andF.P. Binkowski. 1992.
  Body  size and the ontogeny  of the functional response in
  fishes. Can. J. Fish. Aquat. Sci. 49:805-812.

Milton,P. 1971. Oxygen consumption and osmoregulation in the
  shanny, Blenniuspholis. J. Mar. Biol. Ass. U.K. 51:247-265.

Minns, C.K. 1995. Allometry of home range size in lake and
  river fishes. Can. J. Fish. Aquat. Sci. 52:1499-1508.

Minor, J.D. andE.J. Grossman. 1978. Home range and seasonal
  movements of muskellunge as determined by radiotelemetry.
  Am. Fish. Soc. Spec. Publ. 11:146-153.

Minton, J.W. andR.B. McLean.  1982. Measurements of growth
  and  consumption of  sauger  (Stizostedion  canadense):
  Implications for fish energetics studies.  Can. J. Fish. Aquat.
  Sci. 39:1396-1403.

Mittelbach, G.G.  and L.  Persson. 1998. The ontogeny  of
  piscivory and its ecological consequences.
Can. J. Fish. Aquat. Sci. 55:1454-1465.

Mitz, S.V. and M.C. Newman.  1989.  Allometric relationship
  between  oxygen  consumption and   body  weight   of
  mosquitofish, Gambusiaaffmis. Environ. Biol. Fishes 24:267-
  273.

Moharram, Y.G., S.A. El-Sharnouby, E.K. Moustaffa, and A.
  El-Soukkary. 1987. Mercury  and selenium in bouri (Mugil
  cephalus). Water Air Soil Pollut. 32:455-459.

Moore, C.M., RJ. Neves, JJ. Ney, and O.K. Whitehurst. 1985.
  Utilization of alewives and gizzard  shad by striped bass in
  Smith Mountain Lake, Virginia. Proc. Annu. Conf. Southeast.
  Assoc. Fish and Wildl. Agencies 39:108-115.

Morishita, T., U. Kazuaki, N. Imura, and T. Takahashi.  1987.
  Variation with growth in the  proximate compositions  of
  cultured  red  sea  bream.   Nippon  Suisan  Gakkaishi
  53:1601-1607.

Muir, B.S. and C.E. Brown. 1971. Effects of blood pathway on
  the blood-pressure drop in fish gills, with special reference to
  tunas. J. Fish. Res. Bd. Canada 28:947-955.

Muir, B.S. and G.M. Hughes. 1969. Gill dimensions for three
  species of tunny. J. Exp. Biol. 51:271-285.
  Lockhart.  1992. Dietary 2,3,7,8-tetrachlorodibenzofuran in
  rainbow trout: accumulation, disposition, and heptatic mixed-
  function oxidase enzyme induction. Toxicol. Appl. Pharma.
  117:65-74.

Muller-Feuga, A., J. Petit, and JJ. Sabaut. 1978. The influence
  of temperature and wet weight on the oxygen demand of
  rainbow  trout  (Salmo  gairdneri  R.)  In fresh  water.
  Aquaculture 14:355-363.

Mullins, LJ. 1954.  Some physical mechanisms  in narcosis.
  Chem. Rev. 54:289-323.

Munn, M.D. and  T.M.  Short. 1997. Spatial heterogeneity of
  mercury bioaccumulationby walleye inFranklinD. Roosevelt
  Lake and the upper Columbia River, Washington. Trans. Am.
  Fish. Soc.  126:477-487.

Munshi,   J.S.D.,   J.O.   Ojha,   and  A.L.  Sinha.   1980.
  Morphometrics of the respiratory organs of an air-breathing
  catfish, Glorias batrachus (Linn.) in relation to body weight.
  Proc. Indian Natn. Sci. Acad. B 46:621-635.

Murphy, P.O. and J.V. Murphy.  1971. Correlations between
  respiration and  direct uptake of DDT in the mosquito fish
  Gambusiaaffmis. Bull. Environ. Contam. Toxicol. 6:581-588.

Myers, R.A. 1997. Comment and reanalysis: paradigms  for
  recruitment studies. Can. J. Fish. Aquat. Sci. 54:978-981.

Myers, R.A. and N.J. Barrowman.  1996. Is fish recruitment
  related to spawner abundance? Fish. Bull. 94:707-724.

Neely, W.B. 1984. An analysis of aquatic toxicity data: water
  solubility and acute LC50 fish data. Chemosphere 13:813-819.

Nichols, J.W., K.M. Jensen, J.E. Tietge, and R.D. Johnson.
  1998. Physiologically based toxicokinetic model for maternal
  transfer of 2,3,7,8-tetrachlorodibenzo-/>-dioxin in brook trout
  (Salvelinus fontinalis).  Environ. Toxicol. Chem. 12:2422-
  2434.

Niimi, A.J.  and F.W.H.  Beamish.  1974. Bioenergetics and
  growth of largemouthbass (Micropterus salmoides) in relation
  to body weight and temperature. Can. J. Zool. 52:447-456.

Niimi, A.J. and S.L. Morgan. 1980. Morphometric  examination
  of the gills of walleye, Stizostedion vitreum vitreum (Mitchill)
  and rainbow trout, Salmo gairdneri Richardson.  J. Fish Biol.
  16:685-692.
Muir, D.C.G., A.L. Yarechewski, D. A.  Metner,  and W.L.    Niimi, A.J.  and E.G. Oliver.  1987. Influence of molecular
                                                        72

-------
weight  and molecular volume  on the  dietary absorption
efficiency of chemicals by fish.  Can.  J. Fish. Aquat. Sci.
45:222-227.

Niva, B., J. Ojha, and J.S.D. Munshi. 1981. Morphometrics of
  the respiratory organs of an estuarine gobby, Boleophthalmus
  boddaeti. Japan. J. Ichthyol. 27:316-326.

Nordlie, F.G., S.L. Walsh, D.C. Haney, and T.F. Nordlie. 1991.
  The influence of ambient salinity on routine metabolism in the
  teleostCyprinodonvariegatusLacepede. J. FishBiol. 38:115-
  122.

Norheim, G. and S.O. Roald. 1985. Distribution and elimination
  of   hexachlorobenzene,  octachlorostyrene,   and
  decachlorobiphenyl in rainbow trout, Salmogairdneri. Aquat.
  Toxicol. 6:13-24.

Norstrom, R.J., A.E. McKinnon, and A.S.W. deFreitas. 1976. A
  bioenergetics-based model for pollutant accumulationby fish.
  Simulation of PCB and methylmercury residue  levels  in
  Ottawa River yellow perch (Percaflavescens). J. Fish. Res.
  Bd. Canada 33:248-267.

Norton,  J.P.  1996.  Roles  of  deterministic  bounding  in
  environmental modelling. Ecol.  Model. 86:157-161.

O'Hara, J. 1968. The influence of weight and temperature on the
  metabolic rate of sunfish. Ecology 49:159-161.

Oikawa,  S.  and Y. Itazawa. 1984. Allometric relationship
  between tissue respiration and body mass in the carp. Comp.
  Biochem. Physiol. 77A:415-418.

Oikawa, S. and Y. Itazawa. 1985. Gill and body surface areas of
  the carp in relation to body mass, with special reference to the
  metabolic-size relationship. J. Exp. Biol. 117:1-14.

Ojha, J. and J.S.D. Munshi. 1974.  Morphometric studies of the
  gill and skin dimensions in relation  to body weight in a
  fresh-water mudeel, Macrognathus aculeatum (Bloch). Zool.
  Anz., Jena 193:364-381.

Ojha, J., and J.S.D. Munshi. 1976. Morphometric estimation of
  gill diffusing capacity of a fresh-water mudeel, Macrognathus
  aculeatum (Bloch), in relation to body weight. Zoologische
  Beitrage 22:87-98.

Ojha, J., N.C. Rooj, and J.S.D. Munshi. 1982. Dimensions of
  the gills of an Indian hill-stream cyprinid fish, Garra lamta.
  Japan. J. Ichthyol. 29:272-278.
Ojha, J.,  R.  Singh,  and N.K.  Singh.  1985. Structure  and
  dimensions of the respiratory organs of a freshwater catfish,
  Mystus  cavasius (Ham.).  Proc. Indian Natn. Sci. Acad. B
  51:202-210.

Olem, H., S.  Livengood, and K.M.  Sandra.  1992. Lake  and
  reservoir management. Water Environ. Res. 64:523-531.

O'Loughlin, E.J., S.J. Traina, and Y.-P. Chin. 2000. Association
  of organotin compounds with aquatic and terrestrial humic
  substances. Environ. Toxicol. Chem. 19:2015-2021.

Olson, R.J. and A.J. Mullen.  1986. Recent developments for
  making  gastric evacuation and  daily ration determinations.
  Environ. Biol. Fishes 16:183-191.

Opperhuizen, A. and S.M. Schrap. 1988. Uptake efficiencies of
  two polychlorobiphenyls in fish after dietary exposure to five
  different concentrations. Chemosphere 17:253-262.

Opstevdt, J., R. Miller, R.W. Hardy, and J. Spinelli. 1984. Heat-
  induced changes in sulfhydryl groups and disulfide bonds in
  fish protein and their effect on  protein and amino acid
  digestibility in rainbow trout (Salmogairdneri).]. Agnc. Food
  Chem. 32:929-935.

Overton, E.  1901. Studien tiber die Narkose, zugleich  ein
  BeitragzurallgemeinerPharmakologie. Gustav Fischer. Jena,
  Germany.

Parks, J.W., C. Curry,  D. Romani,  and D.D. Russell.  1991.
  Young  northern  pike, yellow  perch  and  crayfish  as
  bioindicators inamercury contaminated watercourse. Environ.
  Monit. Asses. 16:39-73.

Parsons, J.W. 1971. Selective food preferences of walleyes of
  the 1959 year class  in Lake Erie. Trans.  Am. Fish. Soc.
  100:474-485.

Paulson, L.J.  1980. Models of ammonia excretion for  brook
  trout  (Salvelinus fontinalis)  and  rainbow  trout (Salmo
  gairdneri).  Can. J. Fish. Aquat.  Sci. 37:1421-1425.

Perna, S.A. and M.N. Fernandes. 1996. Gill morphology of a
  facultative   air-breathing  loricariid   fish,   Hypostomus
  plecostomus (Walbaum) with special emphasis to aquatic
  respiration. Fish Physiol. Biochem. 15:213-220.

Persson, A.  and  L.-A. Hansson.  1999.  Diet shift in fish
  following competitive  release. Can.  J. Fish. Aquat. Sci.
  56:70-78.
                                                         73

-------
Peters. R.H. and  J.V.  Raelson  1984. Relations between
  individual size and mammalian population density. Am. Nat.
  124:498-517.

Petersen,  J.H.  and D.L.  Ward.  1999.  Development  and
  corroboration  of a  bioenergetics   model  for northern
  pikeminnow feeding on juvenile salmonids in the Columbia
  River. Trans. Am. Fish. Soc. 128:784-801.

Peterson,  D.R.  1994.  Calculating  the  aquatic  toxicity of
  hydrocarbon mixtures. Chemosphere 29:2493-2506.

Peterson, I. and J.S. Wroblewski. 1984. Mortality rates of fishes
  in the pelagic ecosystem. Can. J. Fish. Aquat. Sci. 41:1117-
  1120.
  models for predicting the uptake of chlorinated hydrocarbons
  by oligochaetes. Ecotox. Environ. Safe. 26:166-180.

Rand, P.S., D.J. Stewart, P.W. Seelbach, M.L. Jones, L.R.
  Wedge. 1993. Modeling steelhead population energetics in
  Lakes Michigan and Ontario. Trans. Am. Fish. Soc. 122:977-
  1001.

Randall,  R.G., J.R.M.  Kelso, and C.K.  Minns.  1995. Fish
  production in freshwaters: Are rivers more productive than
  lakes? Can. J. Fish. Aquat. Sci. 52:631-643.

Rao, G.M.M.  1968.  Oxygen consumption of rainbow trout
  (Salmo gairdneri) in relation to activity and salinity. Can. J.
  Zool. 46:781-786.
Pierce, R.J. and T.E. Wissing.  1974. Energy cost of food
  utilization in the bluegill (Lepomis macrochirus). Trans. Am.
  Fish. Soc. 103:38-45.

Pierce, R.J., T.E. Wissing, andB.A. Megrey. 1981. Respiratory
  metabolism of gizzard shad. Trans. Am. Fish. Soc. 110:51-55.

Piiper, J., P.  Scheid, S.F.  Perry, and G.M. Hughes.  1986.
  Effective and morphological oxygen-diffusing capacity of the
  gills of the elasmobranchScyliorhinusstellaris. J. Exp. Biol.
  123:27-41.
Rashevsky, N. 1959. Some remarks on the mathematical theory
  of nutrition of fishes. Bull. Math. Biophys. 21:161-183.

Rayner, J.M.V. 1985. Linear relations in biomechanics: the
  statistics of scaling functions. J. Zool. (London) 206:415-439.

Richards,  C.D., K. Martin,  S. Gregory, C.A. Keightley, T.R.
  Hesketh, G.A. Smith, G.B. Warren, and J.C. Metcalfe. 1978.
  Degenerate  perturbations  of  protein  structure   as  the
  mechanism of anaesthetic action. Nature (London) 276:775-
  779.
Playle, R.C., D.G. Dixon, and K. Burnison. 1993. Copper and
  cadmium binging to fish gills: estimates of metal-gill stability
  constants and modelling of metal accumulation. Can. J. Fish.
  Aquat. Sci. 50:2678-2687.

Post,  J.R. 1990. Metabolic allometry  of  larval and juvenile
  yellow perch (Perca flavescens)  :  In  situ estimates  and
  bioenergetic models. Can. J. Fish. Aquat. Sci. 47:554-560.

Press,  W.H.,  S.A.  Teukolsky, W.T.  Vetterling,  and B.P.
  Flannery. 1992.NumericalRecipesinFORTRAN. Cambridge
  Univ. Press, pp 963.

Price,  J.W.   1931.  Growth and  gill  development  in  the
  small-mouthed black bass, Micropterus dolomieu, Lacepede.
  Ohio  State University, Franz Theodore Stone Laboratory
  4:1-46.
Ricker, W.E. 1979. Growth rates and models. In: W.S. Hoar,
  D.J.  Randall,  and J.R. Brett (editors). Fish  Physiology.
  Volume VIII. Academic Press, Inc. pp. 677-743.

Robinson, J.G. and K.H.  Redford. 1986. Body size, diet and
  population density of neotropical forest mammals. Am. Nat.
  128:665-680.

Robotham, P.W.J. 1978.  The dimensions of the gills of two
  species of loach, Noemacheilus barbatulus and Cobitis taenia.
  J. Exp. Biol. 76:181-184.

Roch, M., J.A. McCarter, A.T.  Matheson, M.J.R. Clark, and
  R.W. Olafson. 1982. Hepatic metallothionein in rainbow trout
  (Salmo gairdneri) as an indicator of metal pollution in the
  Campbell River system. Can.  J. Fish. Aquat. Sci. 39:1596-
  1601.
Pringle, M.J., K.B. Brown, andK.W. Miller. 1981. Can the lipid
  theories of anesthesia account for the cutoff in anesthetic
  potency in homologous series of alcohols. Mol. Pharmacol.
  19:49-55.
Roell, M.J. and D.J. Orth. 1993. Trophic basis of production of
  stream-dwelling  smallmouth bass, rock bass,  and flathead
  catfish in  relation to invertebrate bait  harvest. Trans. Am.
  Fish. Soc.  122:46-62.
Ram, R.N. and J.W. Gillett.  1993. Comparison of alternative    Roex, E.W.M., C.A.M. van Gestel, A.P. van Wezel, and N.M.
                                                         74

-------
van Straalen. 2000. Ratios between acute toxicity and effects on
population growth rates in relation to toxicant mode of action.
Environ. Toxicol. Chem. 19:685-693.

Roesijadi, G. 1992. Metallothionein in metal regulation and
  toxicity in aquatic animals. Aquat. Toxicol. 22:81-114

Rombough, P.J.  and  B.M.  Moroz. 1990.  The scaling and
  potential importance of cutaneous and branchial surfaces in
  respiratory   gas  exchange  in  young   chinook   salmon
  (Oncorhynchus tshawytscha). J. Exp. Biol. 154:1-12.

Rose, K.A., E.S. Rutherford, D.S. McDermot, J.L. Forney, and
  E.L. Mills. 1999. Individual-based model of yellow perch and
  walleye populations in Oneida Lake. Ecological Monographs
  69:127-154.

Roubal, F.R.  1987. Gill surface are and its components in the
  yellowfin bream, Acanthopagrus australis (Gtinther) (Pisces:
  Sparidae) Aust. J. Zool. 35:25-34.

Roy,  P.K. and J.S.D. Munshi.  1986.  Morphometrics of the
  respiratory  organs of a freshwater  major carp, Cirrhinus
  mrigala in  relation to  body  weight. Japan. J.  Ichthyol.
  33:269-279.

Roy, P.K.  and J.S.D. Munshi. 1987. Diffusing capacity (oxygen
  uptake efficency) of the gills  of a freshwater major carp,
  Cirrhinus mrigala (Ham.) in relation to body weight.  Proc.
  Indian Natn. Sci. Acad. 653:305-316.
  Am. Fish. Soc. 128:414-435.

Schnute, J. 1981. A versatile growth model with statistically
  stable parameters. Can. J. Fish. Aquat. Sci. 38:1128-1140.

Scott, D.P. andF.A.J. Armstrong. 1972. Mercury concentration
  in relation to size in several species of freshwater fish from
  Manitoba and northwestern Ontario. J. Fish. Res. Board Can.
  29:1685-1690.

Severi, W., F.T. Rantin, andM.N. Fernandes. 1997. Respiratory
  gill surface of the serrasalmid fishPiaractus mesopotamicus.
  J. Fish Biol. 50:127-136.

Shakuntala, K.  and  S.R. Reddy. 1977.  Influence of body
  weight/age  on  the  food intake,  growth and conversion
  efficiencies of Gambusia affinis. Hydrobiol. 55:65-69.

Sharma, S.N., G.  Guha, andB.R. Singh. 1982. Gill dimensions
  of ahillstreamfish, Botia lohachata (Pisces, Cobitidae). Proc.
  Indian Natn. Sci. Acad. B 48:81-91.

Shubina, L.I. and T.L. Rychagova. 1981. Dynamics of fat and
  water metabolism in Caspian shad, Alosa caspia caspia, in
  relation  to its biological peculiarities. J. Ichthyol. (English
  Translation) 21(6): 123-127.

Shultz, C.D., D.  Crear, J.E. Pearson, J.B. Rivers,  and  J.W.
  Hylin. 1976. Total and  organic mercury in the Pacific blue
  marlin. Bull. Environ. Contam. Toxicol.  15:230-234.
Salam, A. and P.M.C. Davies. 1994. Effect of body weight and
  temperature on the maximum daily food consumption ofEsox
  lucius. J. Fish Biol. 44:165-167.

Santos, C.T.C.,  M.N.  Fernandes,  and  W.  Severi.  1994.
  Respiratory gill surface area of a facultative air- breathing
  loricariid  fish,   Rhine lepis  strigosa.  Can.   J.  Zool.
  72:2009-2015.

Saunders, R.L. 1962. The irrigation of the gills in fishes. II.
  Efficiency of oxygen uptake in relation to respiratory flow
  activity and concentrations of oxygen and carbon dioxide.
  Can. J. Zool. 40:817-862.

Savitz, J. 1969. Effects of temperature and body weight on
  endogenous nitrogen excretion in  the  bluegill sunfish
  (Lepomis macrochirus). J. Fish. Res. Bd.  Canada 26:1813-
  1821.

Schaeffer, J.S., R.C. Haas,  J.S. Diana, and J.E. Breck. 1999.
  Field test of two energetic models for yellow perch. Trans.
Sijm, D.T.H.M. and A. van der Linde.  1995. Size-dependent
  bioconcentration kinetics of hydrophobic organic chemicals in
  fish  based  on  diffusive  mass transfer  and  allometric
  relationships. Environ. Sci. Technol. 29:2769-2777.

Sijm,  D.T.H.M.,  P. Part, and  A. Opperhuizen. 1993. The
  influence of temperature on  the uptake rate  constants of
  hydrophobic compounds determined by the isolated perfused
  gills of rainbow trout (Oncorhynchus mykiss). Aquat. Toxicol.
  25:1-14.

Sijm, D.T.H.M., M.E. Verberne, P. Part, and A. Opperhuizen.
  1994.Experimentally  determined blood and water  flow
  limitations  for  uptake  of hydrophobic compounds using
  perfused gills  of rainbow  trout (Oncorhynchus mykiss):
  allometric applications.  Aquat. Toxicol. 30:325-341.

Sijm, D.T.H.M., M.E. Verberne, W.J. de Jonge, P. Part, and A.
  Opperhuizen. 1995. Allometry in the uptake of hydrophobic
  chemicals determined by in vivo and in isolated perfused gills.
  Toxicol. Appl. Pharmacol. 131: 130-135.
                                                         75

-------
Simkiss, K.  1983. Lipid solubility of heavy metals in saline
  solutions. J. Mar. Biol. Assoc., U.K. 63:1-7.

Singh, B.R., A.N. Yadav, J. Ojha, and J.S.D.  Munshi. 1981.
  Gross structure and dimensions of the gills of an intestinal
  air-breathing  fish  (Lepidocephalichthys guntea).  Copeia
  1981(l):224-229.

Singh, O.N. and J.S.D. Munshi. 1985. Oxygen uptake in relation
  to body weight, respiratory surface area and  group size in a
  freshwater goby, Glossogobius giuris (Ham.). Proc. Indian
  Natn. Sci. Acad. B 51:33- 40.

Singh,  O.N.,  P.K.  Roy,  and  J.S.D.  Munshi.  1988.  Gill
  dimensions of an Indian hill-stream cyprinid fish, Botia dario
  (Ham.) Arch. Biol.  (Bruxelles) 99:162-182.

Sompongse,  W., Y.  Itoh, and A. Obatake. 1996.  Effect of
  cryoprotectants and a reducing reagent on the stability of
  actomyosin during ice storage. Fisheries Science 62:73-79.

Sprenger,  M.D.,  A.W. Mclntosh,  and  S.  Hoenig.  1988.
  Concentrations of trace elements in the yellow perch (Perca
  flavescens) from six acidic lakes. Water Air Soil Pollut.
  37:375-388.

Stafford, C.P. and T.A.  Haines. 1997. Mercury concentrations
  in Maine sport fishes. Trans. Am. Fish. Soc. 126:144-152.

Staples, D.J. and M. Nomura. 1976. Influence of body size and
  food ration on the energy budget of rainbow trout Salmo
  gairdneri Richardson. J. Fish Biol. 9:29-43.

Starmach, J. 1971. Oxygen consumption and respiratory surface
  of gills in Coituspoecilopus Heckel and Coitus gobio L. Acta
  Biol. Cracov. Ser. Zool. 14:9-15.

Steen, J.B. and T.  Berg. 1966. The gills of two species of
  haemoglobin-free fishes compared to those of other teleosts-
  with a note on severe anaemia in an eel. Comp.  Biochem.
  Physiol.  18:517-526.

Steingrimsson, S.O.  and J.W.A. Grant.  1999. Allometry of
  territory size and metabolic rate as predictors  of self thinning
  inyoung-of-year Atlantic salmon. J. Anim. Ecol. 68:17-86.

Stevens, E.D.  1992. Gill  morphometry of the red  drum,
  Sciaenops ocellatus. Fish Physiol. Biochem. 10:169-176.

Stevens, E.D. and E.N. Lightfoot.  1986. Hydrodynamics of
  water flow in front of and through the gills of skipjack tuna.
  Comp. Biochem. Physiol.  83A:255-259.
Stewart,  D.J.  and P.P.  Binkowski.  1986.  Dynamics  of
  consumptionandfoodconversionby Lake Michiganalewives:
  An energetics-modeling synthesis. Trans. Am.  Fish. Soc.
  115:643-661.

Stewart, D.J. andM. Ibarra. 1991. Predation and production by
  salmonine fishes in Lake Michigan, 1978-88. Can. J. Fish.
  Aquat. Sci. 48:909-922.

Stewart, D.J., D. Weininger, D.V. Rottiers, and T.A. Edsall.
  1983.  An  energetics  model  for  lake  trout  Salvelinus
  namaycush:  application to the Lake Michigan population.
  Can. J. Fish. Aquat. Sci. 40:681-698.

StiefVater, R.J. and S.P. Malvestuto. 1985. Seasonal analysis of
  predator-prey size relationships in West Point Lake, Alabama-
  Georgia. Proc. Annu. Conf. Southeast. Assoc. Fish and Wildl.
  Agencies 39:19-27.

Storck, T.W. 1986. Importance of gizzard shad in the diet of
  largemouthbass inLake Shelbyville, Illinois. Trans. Am. Fish.
  Soc. 115:21-27.

Stow, C.A. and S.R. Carpenter.  1994. PCB accumulation in
  Lake Michigan coho and chinook salmon: individual-based
  models using allometric relationships. Environ. Sci. Technol.
  28:1543-1549.

Summers, J.K., H.T. Wilson, and J. Kou. 1993. A method for
  quantifying the prediction uncertainties associated with water
  quality models. Ecol. Model. 65:161-176.

Swartzman,  G.L.,  and  R. Bentley.  1979.  A  review  and
  comparison of plankton simulation  models. ISEM Journal
  1:30-81.

Takashi, R. 1973. Studies on muscular proteins of fish  - VIII.
  Comparative studies on the biochemical properties of highly
  purified myosins from fish dorsal and rabbit skeletal muscle.
  Bull. Japan. Soc. Sci. Fish. 39:197-205.

Takeda,  H.   and  C.   Shimizu.  1982.  Purification  of
  metallothionein from the liver of skipjack and its properties.
  Bull. Japan. Soc. Sci. Fish. 48:717-723.

Tandler,  A. and F.W.H. Beamish.  1981.  Apparent specific
  dynamic action (SD A), fish weight and level of caloric intake
  in the largemouth bass, Micropterus salmoides. Aquaculture
  23:231-242.

Tarby,  M.J.  1980.  Metabolic  expenditure  of  walleye
  (Stizostedion  vitreum  vitreum)  as determined by rate of
                                                         76

-------
oxygen consumption. Can. J. Zool. 59:882-889

Tas, J.W., W. Seinen, and A. Opperhuizen. 1991. Lethal body
  burden of triphenyltin chloride in fish: preliminary results.
  Comp. Biochem. Physiol. 100C:59-60.

Thomann,  R.V.  1981.  Equilibrium  model  of  fate  of
  microcontaminants in diverse aquatic food chains. Can. J.
  Fish. Aquat. Sci. 38:280-296.

Thomann, R.V.  1989. Bioaccumulation  model  of organic
  chemical distribution in aquatic food chains. Environ. Sci.
  Technol. 23:699-707.

Thomann, R.V. and J.P. Connolly. 1984. Model of PCB in the
  Lake Michigan lake trout food chain. Environ. Sci. Technol.
  18:65-71.

Thomann, R.V. J.P. Connolly, and T.F. Parkerton 1992.  An
  equilibrium  model of organic chemical  accumulation in
  aquatic  food webs  with  sediment interaction.  Environ.
  Toxicol. Chem.  11:615-629.

Thornton, K.W.  and A.S.  Lessem.  1978.  A  temperature
  algorithm for modifying biological  rates. Trans. Am. Fish.
  Soc. 107:284-287.

Thurston,  R.V. and P.C.  Gehrke. 1993. Respiratory oxygen
  requirements of fishes: description of OXYREF, a datafile
  based on test results reported in the published literature. In:
  R.C. Russo and R.V. Thurston (editors).  Proceedings of the
  Second International Symposium on Fish  Physiology, Fish
  Toxicology, and Water Quality Management.  Sacramento,
  CA, Sept.  18-20, 1990.  U.S.  Environmental Protection
  Agency, Office of Research and Development.

Timmons, T.J.,  W.L.  Shelton,  and  W.D. Davies. 1980.
  Differential  growth  of largemouth bass in  West Poit
  Reservoir, Alabama-Georgia. Trans. Am. Fish. Soc. 109:176-
  186.

Tracey,  D.M. 1993. Mercury levels in  black  cardinalfish
  (Epigonus telescopus). New Zealand Journal of Marine and
  Freshwater Research 27:177-181

Tuurala, H.,  S. Egginton, and A. Soivio. 1998. Cold exposure
  increases branchial water-blood barrier  in the eel. J. Fish
  Biol.53:451-455.

Ueda, T. and M. Takeda. 1983. Mercury and selenium levels in
  two species of sharks. Bull. Jap. Soc. Sci. Fish. 49:1731-1735.
  (In Japanese)
Umezawa, S.-I. and H. Watanabe. 1973. On the respiration of
  the killifish Oryzias latipes. J. Exp. Biol. 58:305-325.

vanHoogen, G. and A. Opperhuizen. 1988. Toxicokinetics of
  chlorobenzenes in fish. Environ. Toxicol. Chem. 7:213-219.

van Loon, W.M.G.M., M.E.Verwoerd, F.G. Wijnker, C.J. van
  Leeuwen,  P. van  Duyn, C. van  de Guchte,  and J.L.M.
  Hermens. 1997. Estimating total body residues and baseline
  toxicity of complex organic mixtures in effluents and surface
  waters. Environ. Toxicol. Chem. 16:1358-1365.

van  Wezel,  A.P.,  D.T.H.M. Sijm,  W.  Seinen, and  A.
  Opperhuizen. 1995. Use of lethal bod burdens to indicate
  species differences in susceptibility to narcotic toxicants.
  Chemosphere 31:3201-3209.

van Veld, P.A., M.E. Bender, and M.H. Roberts, Jr.  1984.
  Uptake, distribution, and clearance of chlordecone by channel
  catfish (Ictaluruspunctatus). Aquat. Toxicol. 5:33-49.

Veith, G.D.,D.J. Call, andL.T. Brooke. 1983. Structure-toxicity
  relationships for the fathead minnow, Pimephales promelas:
  narcotic industrial chemicals.  Can.   J. Fish.  Aquat. Sci.
  40:743-748.

Verhaar, H.J.M., F.J.M. Busser, and J.L.M. Hermans.  1995.
  Surrogate  parameter for the baseline toxicity  content  of
  contaminated water: simulating  the bioconcentration  of
  mixtures of pollutants and counting molecules. Environ. Sci.
  Technol. 29:726-734.

Vetter, R.D., M.C. Carey, and J.S. Patton. 1985. Coassimilation
  of dietary fat and benzo(a)pyrene in  the small intestine: an
  absorption model using the killifish. J.  LipidRes. 26:428-434.

Walker, G. and T. Davies. 1974. Mass transfer in laminar flow
  between  parallel   permeable  plates.  AIChE  Journal
  20:881-889.

Wallach, D. and M. Genard. 1998. Effect of uncertainty in input
  and parameter values on model prediction error. Ecol. Model.
  105:337-345.

Walter, J. 1973. Regular eigenvalue problems with eigenvalue
  parameter in the boundary condition. Math. Z. 133:301-312.

Wania, F. and D. Mackay. 1999. The evolution of mass balance
  models of persistent organic pollutant fate in the environment.
  Environ. Pollut. 100:223-240.

Wanzenbock, J. and F. Schiemer.  1989. Prey detection  in
                                                        77

-------
cyprinids during early development. Can. J. Fish. Aquat. Sci.
46:995-1001.

Ware, D.M. 1975. Growth, metabolism, and optimal swimming
  speed of a pelagic fish. J. Fish. Res. Bd. Canada 32:33-41.

Wares II, W.D. andR. Igram. 1979. Oxygen consumption in the
  fathead minnow (Pimephales promelas  Rafinesque)  -  I.
  effects of weight, temperature, group size, oxygen level and
  opercular movement rate as a function of temperature. Comp.
  Biochem. Physiol. 62A:351-356.
  bluegill metabolism. Limnol. Oceanogr. 4:195-209.

Wootton, R.J., J.R.M. Allen, and S.J. Cole. 1980. Effect of body
  weight and temperature  on the  maximum daily  food
  consumption of  Gasterosteus aculeatus L.  and Phoxinus
  phoxinus (L.):  selcting an appropriate model. J. Fish Biol.
  17:695-705.

Wren,  C.D.  and  H.R.  MacCrimmon.  1986.  Comparative
  bioaccumulation of mercury in two adjacent ecosystems. Wat.
  Res. 20:763-769.
Watling, R.J., T.P. McClurg, and R.C. Stanton. 1981. Relation
  between mercury concentration and size in the mako shark.
  Bull. Environ. Contam. Toxicol. 26:352-358.

Weatherley, A.H. andH.S. Gill. 1983. Protein, lipid, water, and
  caloric contents of immature rainbow trout, Salmo gairdneri
  Richardson,  growing at different  rates.  J. Fish  Biol.
  23:653-673.
Wright, P.A., D.J. Randall, and S.E. Perry III. 1989. Fish gill
  waterboundary layer: a site of linkage between carbon dioxide
  and ammonia excretion. J. Comp. Physiol. 158:627-635.

Wu, L. and D.A. Culver. 1992. Ontogenetic diet shift in Lake
  Erie age-0 yellow perch (Perca flavescens): A size-related
  response to zooplankton density. Can. J. Fish. Aquat. Sci.
  49:1932-1937.
Weininger, D. 1978. Accumulation of PCBs by lake trout in
  Lake Michigan. University of Wisconsin, Madison, WI. Ph.D.
  thesis, pp. 232.

Werner, E.E. 1974. The fish size, prey size,  handling time
  relation in several sunfishes and some implications. J. Fish.
  Res. Bd. Canada 31:1531-1536.

Werner, E.E. and J.F. Gilliam. 1984. The ontogenetic niche and
  species interactions in size-structured populations. Ann. Rev.
  Ecol. System. 15:393-425.

Wiley, M.J. and L.D. Wike. 1986. Energy balances of diploid,
  triploid, and hybrid grass carp. Trans. Am. Fish. Soc. 115:853-
  863.

Wohlschlag, D.E. andR.O.  Juliano. 1959. Seasonal changes in
Yadav,  A.N.,  M.S. Prasad, and B.R.  Singh.  1990. Gross
  structure of the respiratory organs and dimensions of the gill
  in the mud-skipper, Periophthalmodon schlosseri (Bleeker).
  J. Fish Biol. 37:383-392.

Yalkowsky, S.H., O.S. Carpenter, G.L. Flynn, andT.G. Slunick.
  1973. Drug absorption kinetics in goldfish. J. Pharm. Sci.
  62:1949-1954.

Yalkowsky,  S.H.,  S.C. Valvani, and  D. Mackay.  1983.
  Estimation  of the  aqueous  solubility of  some aromatic
  compounds. Residue Reviews 85:43-55.

Yang, M.S. and P.A. Livingston. 1988. Food habits and daily
  ration of Greenland halibut, Reinhardtius hippoglossoides, in
  the eastern Bering Sea. Fish. Bull. 86:675-690.
                                                        78

-------
                                                APPENDICES
APPENDIX A. Equilibrium complexation model for metals
As  reviewed by Mason and Jenkins (1995),  metals can be
classified  into  three different categories  based  on their
complexation behavior and preference for different ligands.
These groups are generally designated as class A, class B, and
borderline metals. Of these, however, class B  and borderline
metals are the most important from an ecotoxicological point of
view. Class B metals which include Au, Ag, Cu, Hg, and Pb
preferentially bind to marcromolecules such as proteins and
nucleotides that are rich in sulfhydryl groups and heterocyclic
nitrogen. Borderline metals which include As, Cd, Co, Cr, Ni,
Sn, and Zn bind not only to same sites as do class B metals but
also to those sites preferred by class A metals (i.e., carboxylates,
carbonyls, alcohols, phosphates, andphosphodiesters). Although
factors determining the preference of borderline metals for  a
particular binding site are complex, the fact that the transport
and storage of these metals in fish and other biota is regulated by
metallothioneins via sulfhydryl complexation reactions certainly
suggests that the total availability of sulfhydryl groups within
organisms plays a key role in their internal distribution and
accumulation. To formulate complexation reactions for class B
and borderline metals, one can assume that protein sulfhydryl
groups are the only significant ligand for these metals, i.e.,
             RSH + M+ ^ RSM
The stability constant for this reaction is
          Kb  =
[RSM]  [/T] =  RSM [H *]
[RSH]  [Mf]    RSH [M1]
                                 (A-l)
                                                 (A-2)
where [H +] is the hydrogen ion concentration (molar); [M+] is
the  concentration  of  free  metal  (molar);  [RSH]  is  the
concentration of reactive sulfhydryls (molar);  [RSM] is the
concentration of sulfur bound metal (molar); RSM are the moles
of metal bound to sulfhydryls; and RSH are the moles of free
non-disassociated sulfhydryl.  Metal  complexation must be
constrained by mass balances for both the metal and sulfhydryl
binding sites. For the metal itself the following mass balance
must hold
    TM = M + LM + RSM
                                 Kb RSH
                                                 (A-3)
                     TM
            (Pa
                           Kb RSH
                                           where TM are the total moles of metal; LM are the moles of
                                           metal that is partitioned into lipids; and W is the fish's volume
                                           in liters which is approximately equivalent to its kilogram live
                                           weight. The mass balance for the fish' s sulfhydryl content that
                                           must is satisfied is
        TS = RSH
            = RSH  1
                                                                     +     RSM

                                                                                            (A-4)
                                                                                 RSM
                                           where TS denotes the total moles of sulfhydryl ligands; RS' are
                                           the   moles   of   disassociated   sulfhydryls;   and
                                           Ka = [RS~][H+]/[RSH]  is  the  sulfhydryl's  disassociation
                                           constant. In addition to the reaction specified in Eq. (A-l),
                                           mixtures of metals interact by competing for the same binding
                                           site, i.e.,
                                                       RSMt  + M* - RSMj + M*
                                                 (A-5)
The stability constant for this reaction is

                              ]    Kb
                              T  ~ ~Kb.
                                                                               [RSMj]
                    [RSMt]  [Mj]

From this expression it then follows

         RSM. [M.+] Kb i  =  RSM,

      TRSM, [M'] Kb,  =  ]
      •*'	*     .7    '     *    *-
                                   TT           (A-6)
                                                                                                  Kb
                                                                             t  [M/] Kb,
                                                           [M;] Kb, =  [M/] K
                                                                                            (A-7)
                                                    [M/] Kbj
                                                                      RSH
                                                            If Eq.(A-3)  is substituted in this equation, one then obtains

                                                                                           Kb, TM,
                                                RSM. =
                                                                                                 Kb, RSH/[H'}
                                                                          Kbi TUi
                                                                                                             (A-8)
                                                                                [H*} W(Pa + P,Km) + Kb, RSH
                                                        79

-------
This equation in turn can be substituted into Eq.(A-4) to obtain

                   K
  TS = RSH
              1
                             Kb. TM.
                                                  (A-9)
             i    r/f+] W (P  + P, K  )  + Kb. RSH
                 L   J    v a     i   owj       *

For most metals, however,

         [H+] W(Pa  + PtK  ) «  Kb RSH        (A-10)
                            i

Therefore, the sulfhydryl balance  equation is  approximately
equal to
         TS = RSH  1
Thus,
              RSH =
                                                 (A-ll)
                                                 (A-12)
If the metal's aqueous and organic phase concentrations (i.e., Ca
and C0) are expressed on a molar basis, then
                 RSM = C0P0W
                    [Ml  = Ca
                                                 (A-13)
                                                 (A-14)
When Eqs. (A-12), (A-13), and (A-14) are substituted into
Eq.(A-2), one then obtains
            Kb  =
            P C
             O  O
             C
                                   Ka)
                   Ca(TS -
                              i

                     Kb (TS -
                                                 (A-15)
                                  Ka)
which can then be substituted into the equation

            C  -  	°J.	

              0    P.+PlKm + ^
                                  £
                                                 (A-16)
to calculated the fish's aqueous phase concentrations.

To use the above complexation model one must specify both the
metal's stability constant (seeEq.(A-2)) and the concentration of
sulfhydryl  binding  sites (mol  SH/g(DW))  within the fish.
Although numerous studies  have investigated the sulfhydryl
content  of selected fish tissues, it appears that no study has
attempted to quantify the total sulfhydryl content offish. Despite
this situation,  however, a reasonable approximation of this
parameter can still be made since data does exists for the major
tissues (i.e., muscle, liver, kidney, gill, and intestine) typically
associated with metal bioaccumulation.

Itano  and Sasaki (1983) reported the sulfhydryl content of
Japanese sea bass (Lateolabraxjaponicus) muscle to be  11.5
umol(SH)/ g(sacroplasmic  protein)  and  70.5  umol(SH)  /
g(myofibrillar protein). Using the authors  reported values of
0.0578  g(sarcoplasmic protein)  /   g(muscle)  and  0.120
g(myofibrillar protein) / g(muscle) the total sulfhydryl content of
Japanese sea bass  muscle  would be  estimated to be  9.12
umol(SH) / g(muscle) or 45.6  umol(SH) / g(dry  muscle).
Opstevedt et al. (1984) reported the suldhydryl content of Pacific
mackerel (Pneumataphorus japanicus)  and Alaska pollock
(Theragra chalcogramma) muscle to be 6.6 and 6.2 mmol(SH)
/ 16  g(muscle N),  respectively. Using conversion factors
reported by these authors, these values are equivalent to 48.7 and
56.7 umol/g(dry muscle). Chung et al. (2000) determined the
sulfhydryl content of mackerel (Scomber australasicus) muscle
to be 88.2 umol(SH) / g(protein). Using the conversion factor
0.83 g(protein) / g(dry muscle) (Opstevedt et al. 1984) this value
is equivalent to 73.2 umol(SH) / g(dry muscle). Although few
other studies have investigated the sulfhydryl content of whole
fish muscle, several  studies  have reported  on the sulfhydryl
content of the actomyosin  and myosin components of fish
my ofibrillar proteins (Connell and Ho wgate 1959;Buttkus 1967,
1971; Takashi 1973; Itoh et al.1979; Sompongse et  al. 1996;
Benjakul et al. 1997; Lin and Park 1998). Because the results of
these studies agree well with the actomyosin analysis reported by
Itano and Sasaki (1983), it would appear that the results of Itano
and Sasaki (1983), Opstevedt et  al.  (1984), and Chung et al.
(2000) can be applied  to fish in general. Consequently,  the
sulfhydryl content of fish muscle can be assumed to be on the
order of 45-70 umol(SH) / g(dry muscle)

Although the sulfhydryl content  of  liver, kidney,  gills, and
intestine has not been measured directly, the sulfhydryl content
of these tissues  can be estimated from their metallothionein
concentrations. Metallothioneins (MT) are sulfur-rich proteins
which are responsible for the transport and storage of heavy and
trace metals and which are also usually considered to be the
principle source of sulfhydryl  binding sites in  these tissues
(Hamilton  and Mehrle 1986;  Roesijadi  1992).  Numerous
researchers have investigated the occurrence of MTs in the liver,
kidney, and gills of fish, and most have shown that tissue
concentrations of MTs generally vary with metal exposures.
Under moderate exposures typical hepatic MT concentrations in
fish are on the order of 0.03 - 0.30 umol(MT) / g(liver) (Brown
and Parsons 1978; Roch et al.  1982; Klaverkamp and Ducan
1987; Button et al. 1993). Using data from Takeda and Shimizu
                                                         80

-------
(1982) who report the  sulfhydryl content of skipjack tuna
(Katsuwonus pelamis) MTs to be approximately 25 mol(SH) /
mol(MT) and assuming a dry to wet weight ratio equal 0.2, these
MT concentrations would be equivalent to 3.75-37.5 umol(SH)
/ g(dry liver). These values suggest that the hepatic sulfhydryl
content of fish which would include both their baseline MT and
cytoplasmic components that can be converted into MT, might
be on  the order of 40 umol(SH) /  g(dry  liver).  This value,
however, is probably too conservative. Consider, for example,
the observation that the ratios of mercury concentrations in liver
to those in muscle often vary from 1.5 to 6 or more  (Lockhart et
al. 1972;  Shultzetal. 1976; Sprenger et al.  1988).  If liver and
muscle are equilibrating with the same internal aqueous phase,
then either the MT sulfhydryls are more available  than are the
sacroplasmic and  myofibrillar sulfhydryls or the  inducible
concentrations of hepatic MT are much higher than 40 umol(SH)
/ g(dry liver). Of these two possibilities the latter appears more
likely.

Although gill, kidney, and intestine MTs have not been studied
in the same detail that hepatic MTs have been, it  appears that
MT and hence sulfhydryl concentrations in gills and kidney are
lower  and  not  as  inducible  as   hepatic   concentrations
(Klaverkamp and  Ducan  1987; Hamilton et al.  1987a,b).
Klaverkamp and Ducan (1987) estimated the concentrations of
gill MT in white suckers (Catostomus commersoni) to be 33
ug(MT) / g(gill) which is equivalent to 3.3  nmol(MT)  / g(gill)
or 0.0825  umol(SH) /  g(gill). This value  agrees well the
estimated concentrations of unidentified binding sites (0.03 -
0.06 umol / g(gill)) for copper on the gills of rainbow trout
(Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis)
(MacRae et al. 1999) but is somewhat high for the concentration
of unidentified binding sites (0.013 - 0.03  umol / g(gill)) for
copper, cadmium, and silver on the gills of rainbow trout and
fathead minnows (Pimephales promelas) (Playle et al. 1993;
Janes and Playle  1995).

Based on these considerations and the acknowledgment that
many other important organic compounds  contain sulfhydryl
groups, e.g.,  enzymes  such as those  involved in fatty  acid
synthesis, glutathione, etc., it seems reasonable to assume that
the sulfhydryl content of fish is approximately 70 umol(SH) /
g(DW). Because Davis and Boyd (1978) reported the mean sulfur
content of  17 fish species  to  be  206 umol(S) / g(DW), this
assumption implies that almost 1/3  of a fish's sulfur pool exists
as sulfhydryl groups.

The above complexation model was implemented within BASS
using 70 umol(SH) /  g(DW) to calculate the total sulfhydryl
content offish and assuming that the mean dissociation constant
for organic sulfhydryls is pKa=9.25 (i.e., the SPARC estimated
pKa for  cysteine).  Using literature values for the stability
constants of methylmercury, however, BASS overpredicted the
bioammulation of methylmercury in fish by at least an order of
magnitude.   Consequently,  a  much  simpler distribution
coefficient algorithm was adapted.
                                                         81

-------
APPENDIX B. Nondimensionalization of chemical exchange equations for fish gills.

Using the transformations
                  n    C ~ C«
                  ® = n  ^                   (B-l)
                                                          interlamellar channel. Using these observations, one can then
                                                          write
                          h
                         Vh2
the PDE and boundary conditions

             3  /.  .   2\ #C
                1  - X2      =
             2          dy
DdC
   dx
                 ~/;  ,   ~    2zD ridC
                 C(hy) - C  s,	4,  —-
                               <    ^  <3*
can be nondimensionalized into
              3  /,  ^  v2\  d®    d20
              —  (1  - X2-}  —  v	
              2           dY    gx2
                    d@
                    dX
    dX
          = -AU©(UO-
                                JY   dX
      (B-2)

      (B-3)



     (B-4)



     (B-5)


  }
dy\  (B-6)




     (B-7)



     (B-8)



7    (B-9)
The boundary condition (B-9) that describes exchange across the
secondary lamella, however, can be simplified by noting that the
solution of Eq.(B-7) is separable, i.e., ®(X, Y) = &(XyP(Y) and
that qv = h  z  V is the  ventilation volume of an individual
                                                                                    u-^f^  (Y)^\   dY (B-10)

                                                          which can then be differentiated with respect to 7 to obtain
                                                              dY dX
                                                                       TrJTOVf.
                                                                                        %
                                                             ¥(7)
                                                                      dX
                                                                                ¥(7)
                                                                                                         (B-H)
                                                                                                         (B-12)
                                                          Because 1P(7) = exp(-^'3^27) where -%^2 is the constant of
                                                          separation for Eq.(B-7), the preceding equation is equivalent to
                                                                  dX
                                                          which can be manipulated to yield
                                                                                %!2Nsh
                                                                  dX
                                                                         %l2-(2qv/q)N
                                                                                                         (B-13)
                                                                                                         (B-14)
                                                                                        p>"Sh>
                                                          Although this boundary condition is dependent on the eigenvalue
                                                          ^, the eigenvalue expansion for the solution of Eq.(B-7) is still
                                                          straightforward (Walter  1973; Fulton 1977). Note that as the
                                                          fish's perfusion rate  increases,  this  boundary  condition
                                                          converges to
                                                                          dX
                                                                                  ' Jva
                                                                                                         (B-15)
                                                          which is the boundary condition previously used by Barber et al.
                                                          (1991).
                                                       82

-------
APPENDIX C. Derivation of the consistency condition for feeding electivities.

To derive a self consistency condition on a fish'selectivities and    Adding  J^ ff  =  1  to  each side of the above equation one
relative  prey availabilities  such that its  calculate  dietary    obtains the desired result, i.e.,
frequencies will sum to unity, consider the following

                                                                         ^  e'f<   • Y f. = 1
Summing Eq. (C-2) over all / then yields


        E«,-(^+^ =  Ed, -Eft=°       (C-4)
When Eq.(C-3) is substituted into this expression, one then
obtains
                  E        = 0                 (C-5)
                         "i ~ Ji                                                1 -e
                    e' = ~r—f                   (c-i)
                                                 (C-2)                      ~ l-et


                                                 (c-3)                         £ -T7.
                                                        83

-------
APPENDIX D. Example project file constructed using include files as discussed in Section 4.4
/ SIMULATION_CONTROL
/ HEADER  methylmercury bioaccumulation in a "ponded"  everglades community
/ MONTH_TO april
/ LENGTH_OF_SIMULATION  10[year]
/ TEMPERATURE  temp [eelsius]=25.0+10.0*sin(0.172142e-01*t[days]+6.02497)
/ WATER_LEVEL  depth [meter]=file(nonfish.dat)
/ BIOTA benthos [g/mA2]=file(nonfish.dat) ; &
       periphyton[g/mA2]=file(nonfish.dat); &
       zooplankton[mg/1]=file(nonfish.dat)
/ ANNUAL_OUTPUTS 10
/ SUMMARY_PLOTS  pop(length); cfish(length)
!   / SUMMARY_PLOTS  afish(age);  afish(length); afish(weight); &
!                   cfish(age);  cfish(length); cfish(weight); &
!                   baf(age); baf(length); baf(weight);  &
!                   bmf(age); bmf(length); bmf(weight);  &
!                   pop(age); pop(length); pop(weight);  &
!                   age(length);  age(weight); tl(age);  tl(weight);  &
!                   wt(age); wt(length)

!  specify chemical properties and exposures  for methylmercury

#include  'mercury.chm'

!  specify fish community;  full community simulation

#include  'evergldl.cmm'

/ END
                                                                   84

-------
APPENDIX D. (cont.) Include file MERCURY.CHM for methylmercury properties and exposures.
  - Loftus,  W.F., J.C. Trexler,  and R. D.  Jones. 1998 .  Mercury transfer through an
    everglades aquatic food web.  final report contrat SP-329.  Florida Department
    of Environmental Protection.
  - Stober,  J. ,  D. Scheldt,  R.  Jones,  K.  Thornton,  L.  Gandy, J.  Trexler, and
    S. Rathbun.  1998. South Florida ecosystem assessment. EPA-904-R-002
  - Watras,  C. and N. Bloom.  1992 .  Mercury  and methylmercury in  individual
    zooplankton:  implications for bioaccumulation.  Limnol.  Oceanogr. 37:1313-1318.
  cwater [rig/1]     = 1.13
                  = 0 . 15*1.13
  cphytn[ng/g(fw) ] =76.11
                        57 . 85(n=4)    utricularia
                    90 . 44 (n=5)    diatoms
                    76.58(n=3)    chlorophyta
  cinsct [ng/g(fw)] = 212.17
                    258.04(n=9)   dolomedes
                    148.95(n=6)   hydracarina
                    304.29(n=12)  tetragonids
                    136.23(n=15)  unid spiders
  czplnk[ng/g(fw)] = 54.60
                    46 . 35 (ri=10 )
                    62.90(n=12)
                    53.39(n=14)   ostracoda
  cbnths[ng/g(fw)] = 83.91
                    38.03(n=18)   chironomids
                    38.89(n=9)    gastropoda-littoridinops
                    8.92(n=5)     gastropoda-melanoides
                    50.05(n=12)   gastropoda-physella
                    14.21(n=9)    gastropoda-planorbella
                    14.76(n=2)    gastropoda-planorbella
                    19.26(n=13)   gastropoda-pomacea
                    126.55(n=20)  hemiptera-belostoma
                    95.98(n=22)   hemiptera-pelocoris
                    44 . 85 (ri=23)   hyalella
                    91.58(n=25)   odonata-libellulidae
                    186.31(n=41)  palaemonetes
                    18.90(n=8)    pelycepoda-villosa
                    64.33(n=24)   procambarus
  g(dw)/g(fw)    =  0.2  (Watras and Bloom  1992)
  mehg/total  hg  =  0.15 in water (Stober  et  al. 1998)
  mehg/total  hg  =  0.20 in phytoplankton  (Watras and Bloom 1992)
  mehg/total  hg  =  0.60 in zooplankton (Watras and Bloom 1992)
  mehg/total  hg  >  0.90 in fish (Watras and  Bloom 1992)
           cphytn[ppb]=(0.2*16.74/0.2) /(1.13*0.15)*cwater[ng/1];
           czplnk[ppb]=(0.6*54.60/0.2)/(1.13*0.15)*cwater[ng/1];
           cbnths [ppb] = (0.6*83.91/0.2)/(I.13*0.15)*cwater[ng/1]
  end mercury.chm
                                                                    85

-------
APPENDIX D. (cont.) Include file METHYL_HG.PRP for methylmercury properties.
  ref s :
  - Arnold, A.P. and A.J. Canty.  1983 . Methylmercury(II)  sulfhydryl interactions.
    Potentiometric determinations of  the formation constants for complexation of
    methylmercury(II)  by sulfhydryl containing amino acids  and related molecules
    including  gltathione. Can.J.Chem.  61:1428-1434.
  - Benoit, J.M., R.P.  Mason, and C.C. Gilmore.  1999a.  Estimation of mercury-sulfid
    spedation in sediment pore waters using octanol-water  partitioning and implications
    for  availability to methylating bacteria.  Environ.  Toxicol. Chem.  18:2138-2141.
  - Benoit, J.M., C.C.  Gilmore,  R.P.  Mason, and A. Heyes. 1999b. Sulfide controls  on
    mercury spedation and bioavailability to methylating bacteria in sediment pore
    waters. Environ.  Sci. Technol. 33:951-957.
  - Major, M.A., D.H.  Rosenblatt,  and  K.A. Bostian.  1991. The octanol/water
    partition  coeffiecent of methylmercury chloride and  methylmercury hydroxide
    in pure water and salt solutions.  Environ.Toxicol.Chem. 10:5-8.
  - Simpson, R.B. 1961 . Association constants of  methylmercury with sulfhydryl and
    other bases. J.Am.Chem.Soc.  83:4711-4717.

  notes:  Simpson  (1961) reports that  for cysteine log(kb)=log(k2)=7.1 and for
         glutathione log(kb)=log(k2)=6.9. results of Arnold and Canty (1983) ,
         however, estimate log(kb)=log(betallO)-pka=16.46-8.22=8.24.  therefore
         assume  log(kb)=(7.1+8.24)/2=7.67

  CHEMICAL methylmercury
  LOG_KB1 6.00 ! assumed
  LOG_KB2 5.00 ! assumed
  LOG_P  -0.4  ! kow = 0.4 at physiological pH;  see Major  et  al  (1991)
  MOLAR_VOLUME 51 !  calculated  using  liquid referenced molar volume of dimethylmercury
  MOLAR_WEIGHT 215.6
  MELTING POINT  25
                                                                    86

-------
APPENDIX D. (cont.) Include file EVERGLD1.CMM for community structure parameters.
#include 'Igmouth.fsh'
/ ECOLOGICAL_PARAMETERS &
  diet(0<1[mm]<20)={zooplankton=100};  &
  diet(20
-------
APPENDIX D. (cont.) Include file LGMOUTH.FSH for basic largemouth bass parameters.
!  notes:  fish file (*.fsh)  for BASS version 2.1

!  refs:
!  - Barber,  M.C.,  L. A.  Suarez, and R.R. Lassiter.  1991 .  Modelling bioaccumulation of organic
!    pollutants  in  fish  with an application to PCBs in Lake Ontario salmonids.
!    Can.J.Fish.Aquat.Sci.  48:318-337.
!  - Beamish,  F.W.H. 1970.  Oxygen consumption of largemouth bass,  Micropterus  salmoides, in
!    relation to swimming  speed and temperature.  Can.J.Zool.  48:1221-1228.
!  - Beamish,  F.W.H. 1974.  Apparent specific dynamic action of largemouth bass, Micropterus
!    salmoides.  J.Fish.Res.Bd.Can. 31:1763-1769.
!  - Carlander,  K.D. 1977 .  Handbook of Freshwater Fishery Biology, vol  2.  Iowa  State University
!    Press.  Ames, IA.
!  - Glass,  N.R.  1969. Discussion of the calculation of power function  with  special reference to
!    respiratory metabolism in fish. J.Fish.Res.Bd Can.  26:2643-2650.
!  - Lewis,  W.M., R. Heidinger, W. Kirk, W. Chapman, and D.  Johnson.  1974 . Food intake of the
!    largemouth  bass.  Trans.Am.Fish.Soc. 103:277-280.
!  - Lowe, T.P.,  T.W.  May,  W.G. Brumbaugh, and D.A. Kane.  1985 .  National  Contaminant
!    Biomonitoring  Program:  concentrations of seven elements in freshwater fish,  1979-1981.
!    Arch.Environ.Contam.Toxicol. 14:363-388.
!  - Niimi,  A.J.  and F.W.H.  Beamish. 1974. Bioenergetics and growth of  largemouth bass
!    (Micropterus salmoides)  in relation to body weight and temperature.  Can.J.Zool. 52:447-456.
!  - Pandian,  T.J.  and F.J.  Vernberg. 1987 . Animal Energetis - v.  2.  Bivalvia  through Reptilia.
!    Academic Press.
!  - Price,  J.W.  1931. Growth and gill development in the small-mouthed black  bass, Micropterus
!    dolomieu, Lacepede. Ohio State University, Franz Theodore Stone Laboratory 4:1-46.
!  - Schmitt,  C.J.,  and  W.G.  Brumbaugh. 1990 . National Contaminant Biomonitoring  Program:
!    Concentrations of arsenic, cadmium, lead, mercury,  selenium,  and zinc in  U.S. freshwater
!    fish, 1976-1984.  Arch.Environ.Contam.Toxicol.  19:731-747.
!  - Schmitt,  C.J.,  J.L.  Zajicek, and P.H. Peterman.  1990 .  National Contaminant  Biomonitoring
!    Program:  Residues of  organochlorine chemicals in U.S. freshwater fish,  1976-1984. Arch.
!    Environ.Contam.Toxicol.  19:748-781.
!  - Tandler,  A.  and F.W.H.  Beamish. 1981. Apparent specific dynamic action  (SDA), fish weight,
!    and level of caloric  intake in largemouth bass, Micropterus salmoides Lacepede.
!    Aquaculture 23:231-242.
!  - Timmons,  T.J.  and W.L.  Shelton. 1980. Differential growth of  largemouth bass in West Point
!    Reservoir,  Alabama-Georgia. Trans.Am.Fish.Soc. 109:176-186.

/  COMMON_NAME  bass
/  SPECIES  Micropterus  salmoides
/  AGE_CLASS_DURATION  year
/  SPAWNING_PERIOD  may-June
/  ECOLOGICAL_PARAMETERS &
  lp[cm]=0.6 + 0.27*L[cm];  & !  estimated from Timmons and Shelton  (1980) for  Lepomis
  wl [g]=0.0117*L[cm]A3.08;  & ! Carlander  (1977)  0.00543 adjusted  such  that  2.0kg = 50cm
  tl_rO[mm]= 150;   &  !  Carlander  (1977)
  yoy[g]=25.0;  &
  mis [year] =8 ;  &
                                         see sg[] and assume exogenous  mortality/total mortality = .9 and b=l
  pi[-]=0.000121*W[g]A0.845  ! Lowe et al.
  MORPHOMETRIC_PARAMETERS  &
  ga[cmA2]=7.32*W[g]A0.820;  &  ! Price  (1931)
  Id[lamellae/mm_per_side]=31.28*W[g]A(-.072); & !  Price (1931)
  11[cm]=0.0188*W[g]A0.294  ! assumed  (see Barber et al.  1991)
  FEEDING_OPTIONS linear(l
-------
APPENDIX D. (cont.) Include file GAR.FSH for basic Florida gar parameters.
!  notes:  fish file  (*.fsh)  for BASS version 2.1

!  refs:
!  - Barber,  M.C., L.A.  Suarez, and R. R. Lassiter.  1991 .  Modelling bioaccumulation of organic
!    pollutants  in fish  with an application to PCBs in Lake Ontario salmonids.
!    Can.J.Fish.Aquat.Sci.  48:318-337.
!  - Brim et  al.  1993 . Mercury concentrations in largemouth bass and other  fishes of the
!    Loxahatchee National Wildlife Refuge. U.S. Fish and Wildlife Service publ.no. PCFO-EC 93-02.
!  - Carlander,  K.D. 1969.  Handbook of Freshwater Fishery Biology,  vol  1. Iowa  State University
!    Press. Ames,  IA.
!  - Glass, N.R.  1969. Discussion of the calculation of power function  with special reference to
!    respiratory metabolism in fish. J.Fish.Res.Bd Can. 26:2643-2650.
!  - Landolt,  J.C. and L.G.  Hill. 1975.  Observations on the gross structure and dimensions of the
!    gills of  three  species of gars  (Lepisosteidae) .  Coepia 1975(3) :470-475.
!  - Pandian,  T.J. and F.J.  Vernberg. 1987 . Animal Energetis - v.  2.  Bivalvia through Reptilia.
!    Academic  Press.
!  - Rahn, H.,  K.B.  Rahn, B.J. Howell, C. Cans, and S.M.  Tenney. 1971.  Air  breathing of the
!    garfish  (Lepisosteus osseus). Respir.Physiol.  11:285-307.
!  - Smatresk,  N.J.  and  J.N.  Cameron. 1982 . Respiration and acid-base physiology of the spotted
!    gar,  a bimodel  breather II. responces to temperature change and hypercapnia. J.Exp.Biol. 96:281-293.
!  - Winger,  P.V.  and J.K.  Andreasen. 1985 . Contaminant residues in fish and sediments from
!    lakes in  the Atchafalaya River Basin  (Louisiana).  Arch.Environ.Contarn.Toxicol. 14:579-586.

/  COMMON_NAME gar
/  SPECIES Lepisosteus  platyrhincus
/  AGE_CLASS_DURATION  year
/  SPAWNING_PERIOD april-may
/  ECOLOGICAL_PARAMETERS &
  Ip [cm]=0.15*L[cm] ; &  ! assumed
  wl [g]=0.00171*L [cm]A3.30;  & ! Carlander (1969) for L.  osseus 0.00065 adjusted such that 2.3 kg = 720 cm
  tl_rO[mm]=  330;   &  !  Carlander  (1969)
  yoy[g]=25.0;  &
  mis [year] =5 ;  &
  nm[I/day]=1.0*0.882*W [g] A ( - 1 .048) ! see sg[],  assume exogenous mortality/total mortality = 1 and b=l.0
/  COMPOSITIONAL_PARAMETERS &
  pa[-]  = 0.82-1.25*pl [-] ;  & ! assumed  (see Barber et al.  1991)
  pl[-]=0.06  !  Winger and  Andreasen (1985)
/  MORPHOMETRIC_PARAMETERS  &
  ga[cmA2] =3.94*W[g] A0.738;  & ! Landolt and Hill(1975)
  ld[lamellae/mm_per_side]=38.8*W[g]A(-.0603); &  ! Landolt and Hill (1975)
  11[cm]=0.0188*W[g]A0.294 ! assumed (see Barber et al.  1991)
/  FEEDING_OPTIONS linear(l
-------
APPENDIX D. (cont.) Include file BULLHEAD.FSH for basic bullhead parameters.
!  notes:  fish file (*.fsh)  for  BASS version 2.1

!  refs:
!  - Barber,  M.C.,  L. A.  Suarez,  and R.R. Lassiter. 1991 .  Modelling bioaccumulation of  organic
!    pollutants  in  fish  with an  application to PCBs in Lake Ontario salmonids.
!    Can.J.Fish.Aquat.Sci.  48:318-337.
!  - Campbell,  R.D.  and  B.A.  Branson. 1978 . Ecology and population dynamics of  the black
!    bullhead,  Ictalurus melas  (Rafinesque), in central Kentucky. Tulane Studies in Zoology
!    and Botany 20:99-136.
!  - Carlander,  K.D.  1969 .  Handbook of Freshwater Fishery Biology, vol 1.  Iowa  State University
!    Press.  Ames,  IA.
!  - Glass,  N.R.  1969. Discussion  of the calculation of power function with special reference  to
!    respiratory metabolism in fish. J.Fish.Res.Bd.Can. 26:2643-2650.
!  - Lowe, T.P.,  T.W.  May,  W.G.  Brumbaugh, and D.A.  Kane.  1985 .  National Contaminant
!    Biomonitoring  Program:  concentrations of seven elements in freshwater fish,  1979-1981.
!    Arch.Environ.Contam.Toxicol.  14:363-388.
!  - Pandian, T.J.  and F.J.  Vernberg. 1987 . Animal Energetis - v. 2.  Bivalvia through  Reptilia.
!    Academic Press.
!  - Saunders,  R.L.  1962 . The irrigation of the gills  in fishes II.  Efficiency  of oxygen  uptake in
!    relation to respiratory flow, activity and concentrations of oxygen and carbon dioxide.
!    Can.J.Zool.  40:817-862.
!  - Schmitt, C.J.,  and  W.G.  Brumbaugh. 1990 . National Contaminant Biomonitoring Program:
!    Concentrations of arsenic,  cadmium, lead, mercury, selenium, and zinc in U.S.  freshwater
!    fish, 1976-1984.  Arch.Environ.Contam.Toxicol. 19:731-747.
!  - Schmitt, C.J.,  J.L. Zajicek,  and P.H. Peterman.  1990 .  National Contaminant Biomonitoring
!    Program: Residues of organochlorine chemicals in U.S.  freshwater fish, 1976-1984.
!    Arch.Environ.Contam.Toxicol.  19:748-781.

/  COMMON_NAME  bullhead !  yellow  bullhead
/  SPECIES  Ameiurus natalis
/  AGE_CLASS_DURATION year
/  SPAWNING_PERIOD  march-april
/  ECOLOGICAL_PARAMETERS &
  Ip[cm]=0.25*L[cm];  &  ! assumed
  wl [g]=0.0304*L[cm]A2.82;  & !  Carlander  (1969)  adjusted such that 1kg =  40cm
  tl_rO[mm]  = 150;  & !  Carlander  (1969)
  yoy[g]=10.0;  & !  assumed
  mis [year] =5 ;  &
  nm [I/day]=0.90*0.0382*W[g]A(-.537) ! see sg[]  and assume exogenous mortality/total  mortality = 0.9 and b=l
/  COMPOSITIONAL_PARAMETERS &
  pa [-]=0.80-0.94*pl [-] ; & ! Lowe et al.  (1985), Schmitt and Brumbaugh (1990), Schmitt et al.  (1990)
  pl[-]=0.08 !  Lowe et  al.  (1985), Schmitt and Brumbaugh (1990), Schmitt  et al.  (1990)
/  MORPHOMETRIC_PARAMETERS  &
  ga [cmA2]=4.98*W[g]A0.728;  &  ! Saunders  (1962)  for brown bullhead
  id[cm]=9.26e-4*W[g]A0.200;  &  !  Brockway et al. for channel catfish
  Id[lamellae/mm_per_side]= 15.9*W[g]A(-0.00917); & !  Saunders (1962)  for  brown bullhead
  11 [cm]=8.96e-3*W[g]A0.270  !  Brockway et al. for channel catfish
/  FEEDING_OPTIONS  linear(l
-------
APPENDIX D. (cont.) Include file BLUEGILL.FSH for basic bluegill parameters.
!  notes:  fish file (*.fsh)  for BASS version 2.1

!  refs:
!  - Barber,  M.C.,  L. A.  Suarez, and R.R. Lassiter.  1991 .  Modelling bioaccumulation  of organic
!    pollutants  in  fish  with an application to PCBs in Lake Ontario salmonids.
!    Can.J.Fish.Aquat.Sci.  48:318-337.
!  - Carlander,  K.D. 1977 .  Handbook of Freshwater Fishery Biology, vol 2.  Iowa  State University
!    Press.  Ames, IA.
!  - Lowe, T.P.,  T.W.  May,  W.G. Brumbaugh, and D.A. Kane.  1985 .  National  Contaminant
!    Biomonitoring  Program:  concentrations of seven elements in freshwater fish,  1979-1981.
!    Arch.Environ.Contam.Toxicol.  14:363-388.
!  - 0'Kara,  J.  The influence of weight and temperature on the metabolic  rate of  sunfish. Ecology
!    49 : 159-161.
!  - Osenberg,  C.W.  M.H. Olson, and G.G. Mittelbach.  1994. Stage structure in fishes: Resource
!    productivity and  competition  gradients.  In:  D.J.  Stouder, K.L.  Fresh,  R.J. Feller  (eds);
!    M.  Duke (ass.ed.).  Theory and application in fish feeding ecology. University  of South
!    Carolina Press, p 151-170.
!  - Pandian,  T.J.  and F.J.  Vernberg. 1987 . Animal Energetis - v.  2.  Bivalvia through Reptilia.
!    Academic Press.
!  - Pierce,  R.J. and  T.E.  Wissing. 1974. Energy cost of food utilization in the  bluegill  (Lepomis
!    macrochirus) .  Trans.Am.Fish.Soc. ??: 38-44 .
!  - Price,  J.W.  1931.  Growth and  gill development in the small-mouthed black bass, Micropterus
!    dolomieu,  Lacepede. Ohio State University,  Franz Theodore Stone  Laboratory 4:1-46.
!  - Schmitt,  C.J.,  and  W.G.  Brumbaugh. 1990 . National Contaminant Biomonitoring  Program:
!    Concentrations of arsenic, cadmium, lead, mercury, selenium,  and zinc in U.S.  freshwater
!    fish, 1976-1984.  Arch.Environ.Contam.Toxicol.  19:731-747.
!  - Schmitt,  C.J.,  J.L. Zajicek, and P.H. Peterman.  1990 .  National  Contaminant  Biomonitoring
!    Program:  Residues of organochlorine chemicals in U.S. freshwater fish,  1976-1984.
!    Arch.Environ.Contam.Toxicol.  19:748-781.
!  - Wohlschlag,  D.E.  and R.0. Juliano. Seasonal changes in bluegill  metabolism.  Limnog.
!    Oceanog.  4:195-209.

/  COMMON_NAME  bluegill
/  SPECIES  Lepomis macrochirus
/  AGE_CLASS_DURATION  year
/  SPAWNING_PERIOD  april-june
/  ECOLOGICAL_PARAMETERS &
  Ip [cm]=0.15*L[cm] ;  &  ! assumed
  wl [g]=0.0209*L [cm]A3.06;  & ! Carlander  (1977)  adjusted such that 200g  = 20cm
  tl_rO[mm]= 80;   & !  Carlander  (1977)
  yoy[g]=5.0;  & !  assumed
  mis [year] =5 ;  &
  nm[I/day]=0.1*0.75*0.0208*W[g]A(-.615)  ! see sg[]  and assume exogenous mortality/total mortality = 0.1
/  COMPOSITIONAL_PARAMETERS &
  pa [-]=0.781-0.94*pl[-];  & ! Lowe et al. (1985),  Schmitt and Brumbaugh  (1990),  Schmitt et  al.  (1990)
  pl[-]=0.0597  ! Lowe et al.  (1985), Schmitt and Brumbaugh (1990),  Schmitt et  al.  (1990)
/  MORPHOMETRIC_PARAMETERS  &
  ga[cmA2]=7.32*W[g]A0.820;  &  ! Price  (1931)
  id[cm]=1.15e-3*W[g]A0.172; &  !  Brockway et al.
  11[cm]=6.55e-3*W[g]A0.259  ! Brockway et al.
/  FEEDING_OPTIONS  linear(l
-------
APPENDIX D. (cont.) Include file REDEAR.FSH for basic redear sunfish  (shell cracker) parameters.
!  notes:  fish file  (*.fsh)  for BASS version 2.1

!  refs:
!  - Barber,  M.C., L.A.  Suarez, and R. R. Lassiter.  1991 .  Modelling bioaccumulation of organic
!    pollutants  in fish  with an application to PCBs in Lake Ontario salmonids.
!    Can.J.Fish.Aquat.Sci.  48:318-337.
!  - Carlander,  K.D. 1977 .  Handbook of Freshwater Fishery Biology, vol  2.  Iowa  State University
!    Press.  Ames, IA.
!  - Evans,  D.0.  1984 . Temperature independence of  the annual cycle of  standard metabolism in
!    the pumpkinseed.  Trans.Amer.Fish.Soc.  113:494-512.
!  - Lowe, T.P.,  T.W.  May,  W.G. Brumbaugh,  and D.A. Kane.  1985 .  National  Contaminant
!    Biomonitoring Program:  concentrations of seven elements in  freshwater fish,  1979-1981.
!    Arch.Environ.Contarn.Toxicol. 14:363-388.
!  - 0'Kara,  J.  The  influence of weight and temperature on the metabolic  rate of  sunfish. Ecology
!    49:159-161.
!  - Osenberg,  C.W.  M.H. Olson, and G.G. Mittelbach.  1994. Stage structure in fishes: Resource
!    productivity and  competition gradients.  In:  D.J.  Stouder, K.L.  Fresh,  R.J. Feller  (eds);
!    M.  Duke (ass.ed.).  Theory and application in fish feeding ecology. University of South
!    Carolina Press. p 151-170.
!  - Pandian, T.J. and F.J.  Vernberg. 1987 . Animal  Energetis - v.  2.  Bivalvia through Reptilia.
!    Academic Press.
!  - Pierce,  R.J. and  T.E.  Wissing. 1974. Energy cost of  food utilization in the  bluegill  (Lepomis
!    macrochirus) . Trans.Am.Fish.Soc. ??: 38-44 .
!  - Price,  J.W.  1931. Growth and gill development  in the small-mouthed black bass, Micropterus
!    dolomieu,  Lacepede. Ohio State University,  Franz Theodore Stone Laboratory 4:1-46.
!  - Schmitt, C.J.,  and  W.G.  Brumbaugh. 1990 . National Contaminant Biomonitoring  Program:
!    Concentrations  of arsenic, cadmium, lead, mercury, selenium,  and zinc in U.S. freshwater
!    fish, 1976-1984.  Arch.Environ.Contam.Toxicol.  19:731-747.
!  - Schmitt, C.J.,  J.L. Zajicek, and P.H. Peterman.  1990 .  National Contaminant  Biomonitoring
!    Program: Residues of organochlorine chemicals  in U.S. freshwater fish,  1976-1984.
!    Arch.Environ.Contam.Toxicol. 19:748-781.
!  - Wilbur,  R.L. 1969.  The redear sunfish in Florida. Florida Game and Fresh Water Fish
!    Commission.  Fishery Bull no. 5.

/  COMMON_NAME redear  !  shellcraker
/  SPECIES  Lepomis  microlophus
/  AGE_CLASS_DURATION  year
/  SPAWNING_PERIOD may-June
/  ECOLOGICAL_PARAMETERS &
  wl [g]=0.0148*L[cm]A3.08;  & ! Carlander  (1977)  adjusted such that 300g  = 25cm
  tl_rO[mm]= 140;   &  !  Wilbur  (1969)
  yoy[g]=5.0;  & ! assumed
  mis [year] =5 ;  &
  nm[I/day]=0.3*0.75*0.0528*W[g]A(-.761)  ! see sg[]  and  assume  exogenous mortality/total mortality = 0.1
/  COMPOSITIONAL_PARAMETERS &
  pa [-]=0.781-0.941*pl[-];  & ! Lowe et al.  (1985), Schmitt and  Brumbaugh (1990), Schmitt et al.   (1990)
  pl[-]=0.0597  ! Lowe et al.  (1985), Schmitt and Brumbaugh (1990),  Schmitt et  al.  (1990)
/  MORPHOMETRIC_PARAMETERS  &
  ga[cmA2]=7.32*W[g]A0.820;  &  ! Price  (1931)
  id[cm]=1.15e-3*W[g]A0.172; & ! Brockway et al.
  11[cm]=6.55e-3*W[g]A0.259  ! Brockway et al.
/  FEEDING_OPTIONS linear(l
-------
APPENDIX D. (cont.) Include file GAMBUSIA.FSH for basic Gambusia  parameters.
!  notes:  fish file  (*.fsh) for BASS version 2.1

!  refs:
!  - Barber,  M.C., L.A. Suarez,  and R.R.  Lassiter.  1991 . Modelling bioaccumulation of  organic
!    pollutants  in fish with an application to PCBs in Lake Ontario salmonids.
!    Can.J.Fish.Aquat.Sci. 48:318-337.
!  - Haake,  P.W.  and J.M. Dean.  1983 .  Age and growth of  four Everglades fishes  using otolith
!    techniques.  Everglades National Park.  Tech.  Rep. SFRC-83/03. pp 68.
!  - Kushlan,  J.A., S.A. Voorhees,  W.F.  Loftus,  and P.C. Frohring. 1986 . Length,  mass,  and
!    calorific relationships of Everglades  animals.  Fla. Sci. 49:65-79.
!  - Meffe,  G.K.  and F.F. Snelson,  jr.  1993. Lipid  dynamics during reproduction in two
!    livebearing  fishes, Gambusia hoibrooki and Poecilia latipinna.  Can.J.Fish.Aquat.Sci.
!    50 : 2185-2191.
!  - Murphy,  P.G. and J.V. Murphy.  1971 .  Correlations between respiration and direct uptake of
!    DDT  in the mosquito fish Gambusia affinis.  Bull.Environ.Contarn.Toxicol.  6:581-588.
!  - Pandian,  T.J. and F.J. Vernberg.  1987 .  Animal  Energetis - v. 2.  Bivalvia through  Reptilia.
!    Academic Press.

/  COMMON_NAME gambusia ! mosquitofish
/  SPECIES Gambusia affinis
/  AGE_CLASS_DURATION month
/  SPAWNING_PERIOD march-october
/  COMPOSITIONAL_PARAMETERS &
  pa[-]  = 0.82-1.25*pl [-] ; & !  assumed (see Barber et al. 1991)
  pl[-]  = 0.125  ! Meffe and Snelson(1993)
/  ECOLOGICAL_PARAMETERS &
  Ip [mm]= 0.2*L[mm] ; & ! assumed
  log(wl[g])=-4.786+3.032*log(L[mm]);  & !  std len  Kushlan et al. (1986)
  tl_rO[mm]  = 35; &  ! Carlander (1969)
  yoy[g]=0.025;  &  ! assumed
  mis[day]  = 240; &
  nm[I/day]  = 0.1*0.75*0.0027*W[g]A(-0.693) !  see  Haake and Dean below
/  MORPHOMETRIC_PARAMETERS &
  ga[cmA2]  = 2.606*W[g]A0.883;  & !  Murphy  and Murphy (1971)
  Id[lamellae/mm_per_side] = 28.1*W[g]A(-0.0731);  & ! interspecific geometric  mean
  11 [cm]  = 0.0188*W[g]A0.294 !  assumed (Barber et  al. 1991)
/  FEEDING_OPTIONS linear(0
-------
APPENDIX D. (cont.) Include file for nonfish prey and water level.
/OOl time [day]
/002 benthos[g/mA2]
/003 periphyton[g/mA2]
/004 zooplankton[mg/1]
/005 depth[meter]
/start_data
1      5.0    0.0    0.2
5000    5.0    0.0    0.2
                                                         94

-------
APPENDIX E. Example output file (filename.msg) that summarizes user input data, input data errors,
and run time warnings and errors.
 GETINPT:  summary of  user  commands  in compressed format
         / simulation_control
         / header methylmercury bioaccumulation in a "ponded" everglades community
         / month_tO  april
         / length_of_simulation 10[year]
         / temperature  temp [celsius]= 25.0 + 10.0*sin(0.172142e-01*t[days]+6.02497)
         / water_level  depth [meter]=file(nonfish.dat)
         / biota benthos [g/mA2]=file(nonfish.dat) ;  periphyton[g/mA2]=file(nonfish.dat) ;  zooplankton [mg/1]=file(nonfish.dat)
         / annual_outputs  10
         / summary_plots pop(length); cfish(length)
         / chemical  methylmercury
         / log_kbl 6.00
         / Iog_kb2 5.00
         / log_p -0.4
         / molar_volume 51
         / molar_weight 215.6
         / melting_point 25
         / exposure  cwater[ng/1]=0.444;
          czplnk [ppb] = (0.6*54.60/0.2)/(
         / common_name  bass
         / species micropterus salmoides
         / age_class_duration year
         / spawning_period may-June
         / ecological_parameters Ip [cm]=0.6 + 0.27*1[cm] ;  wl[g]=0.0117*1[cm]A3 . 08 ; tl_rO[mm]= 150; yoy[g]=25.0; mis[year]=8;
          nm[ I/day] =0. 9*1. 0*0. 0814 *w[g]A(-. 675)
         / compositional_parameters pa [-]=0.80-1.57*pl[-] ; pi[-]=0.000121*w[g]A0.845
         / morphometric_parameters  ga[cmA2]=7.32*w[g]A0.820;  Id[lamellae/mm_per_side]= 31.28*w[g]A(-.072);
          ll[cm]=0.0188*w[g]A0.294
         / feeding_options linear(l
-------
/ species lepomis macrochirus
/ age_class_duration year
/ spawning_period april-June
/ ecological_parameters Ip [cm]=0.15*1 [cm] ;  wl[g]=0.0209*1[cm]A3.06;  tl_rO[mm]= 80;  yoy[g]=5.0; mis[year]=5;
 nm[ I/day] =0. 1*0. 75*0. 0208 *w[g]A(-. 615)
/ compositional_parameters pa [-]=0.781-0.94*pl[-] ;  pi [-]=0.0597
/ morphometric_parameters ga[cmA2]=7.32*w[g]A0.820;  id[cm]=1.15e-3*w[g]A0.172; ll[cm]=6.55e-3*w[g]A0.259
/ feeding_options linear(l
-------
97

-------
ekeeking user supplied control commands
CHKCTRL WARNING:  insect standing stock not specified
CHKCTRL WARNING:  phytoplankton standing stock not  specified
CHKCTRL: no errors detected
                                                                      98

-------
ambient water temperature	 temp [celsius] = 25.0 + 10.0*sin(6.02 + 1.721E-02*t[day] )
water level	 depth [meter] = C : \BASS\proj ects\examplel\nonf ish . dat, column5
benthos standing stock	 bnths[g(DW)/mA2] =  C:\BASS\proj ects\examplel\nonfish.dat,column2
insect standing stock	 insct[g (DW) /mA2] =  not_specif led
periphyton standing stock	 phytn[g(DW)/mA2] =  C:\BASS\projects\examplel\nonfish.dat,columns
phytoplankton standing stock.... pplnk[g(DW)/I] = not_specifled
zooplankton standing stock	 zplnk[g(DW)/I] = C:\BASS\projects\examplel\nonfish.dat,column4
                                                                      99

-------
100

-------
log_ac	
log_kbl	
Iog_kb2	
log_p	
melting_point.
molar_volume..
molar_weight..
biotransformation rate in bass	
biotransformation rate in gar	
biotransformation rate in bullhead.
biotransformation rate in bluegill.
biotransformation rate in redear...
biotransformation rate in gambusia.
LC50 for bass	 LC50[molar]=0.135E-02*KowA-0.871
LC50 for gar	 LC50[molar]=0.135E-02*KowA-0.871
LC50 for bullhead... LC50[molar]=0.135E-02*KowA-0.871
LC50 for bluegill... LC50[molar]=0.135E-02*KowA-0.871
LC50 for redear	 LC50[molar]=0.135E-02*KowA-0.871
LC50 for gambusia. .  . LC50 [molar]=0.135E-02*KowA-0.871
benthos dietary exposure	 cbnths [ppm] = 1.485E + 06*cwater[ppm]
insect dietary exposure	 cinsct [ppm] = 1.06
periphytic dietary exposure	 cphytn[ppm] = 9.876E + 04*cwater[ppm]
phytoplankton dietary exposure. . .  . cpplnk [ppm] = not_specifled
zooplankton dietary exposure	 czplnk [ppm] = 9.664E + 05*cwater[ppm]
sedimentary exposure	 csdmnt [ppm] = not_specif led
aqueous exposure	 cwater [ppm] = 4.440E-07
                                                                      101

-------
CHKFISH WARNING:  bullhead -  default  reproductive biomass investment assigned
CHKFISH WARNING:  bluegill -  default  reproductive biomass investment assigned
CHKFISH WARNING:  gambusia -  default  reproductive biomass investment assigned
                                                                     102

-------
  assimilation efficiency  (fish)	
  assimilation efficiency  (inverts)..
  assimilation efficiency  (plant)....
  gill area	 ga [cmA2]  =  7.320*W[g]A0.820
  gastric evacuation	 9e [9 (DW) /day]  =  not_specif led
  inter lame liar distance	 id [cm]  = 0.002*W[g]A0.086
  lamellar density	 Id [lamellae/mm]  =  31.280*W[g]A-0.072
  lamellar length	 11 [cm]  = 0.019*W[g]A0.294
  length of prey	 Ip [cm]  = 0 . 600 + 0 . 270*L [cm]
  maximum filtering	 mf [L/day] =  not_specifled
  maximum ingest ion	 nii[g (DW) /day]  =  not_specif led
  maximum longevity	 mis [day]  =  2922 .
  non-predatory mortality	 nm [1/yr]  =  26.8*W[g]A-0.675
  fraction aqueous	 pa [-]  =  0. 800-1. 570*pl[-]
  fraction lipid	 pi [-]  =  0.000*W[g]A0.845
  reproductive biomass investment	 rbi[-]  = 0.150
  respiratory quotient	 rq [- ]  =  1.000
  routine : standard V0_2	 rt: std [-] =  2.000
  SDA: ingest ion ratio	 sda : in [- ] =  0.127
  specific growth rate	 sg [I/day] =  0.014*W[g]A-0. 675*exp (0.069*t[celsius])
  satiation meal size	 sm[g (DW) ] =  not_specif led
  standard V0_2	 so [mg  o2/hr] =  0.119*W[g] A0 . 766*exp(0.043*t [celsius] )
  time to satiation	 st [minutes]  =  not_specif led
  weight: length	 wl[g(FW)] =  0.012*L[cm]A3.080
  length at first reproduction	 tl_rO[cm] =  15.0
  weight of recruits	 yoy[g(FW)]  =25.0
  spawning interval	 may- June =>  day ( s)  =  62 ,
  initial standing stock  ...  20.01  [kg(FW)/ha]

ecotoxicological parameters:

  mean lethal activiy	 la[-] =   1.066E-03
                                                                      103

-------
  assimilation efficiency  (fish)
  assimilation efficiency  (inverts) ..
  assimilation efficiency  (plant)
  gill area	 ga [cmA2]  =  3.940*W[g]A0.738
  gastric evacuation	 9e [9 (DW) /day]  =  not_specif led
  inter lame liar distance	 id [cm]  = 0.002*W[g]A0.072
  lamellar density	 Id [lamellae/mm]  =  38.800*W[g]A-0.060
  lamellar length	 11 [cm]  = 0.019*W[g]A0.294
  length of prey	 Ip [cm]  = 0 . 000 + 0 . 150*L [cm]
  maximum filtering	 mf [L/day] =  not_specifled
  maximum ingest ion	 nii[g (DW) /day]  =  not_specif led
  maximum longevity	 mis [day]  =  1826 .
  non-predatory mortality	 nm [1/yr]  =  322.*W[g]A-1.048
  fraction aqueous	 pa [-]  =  0. 820-1. 250*pl[-]
  fraction lipid	 pi [-]  =  0.060*W[g]A0.000
  reproductive biomass investment	 rbi[-]  = 0.150
  respiratory quotient	 rq [- ]  =  0.900
  routine : standard V0_2	 rt: std [-] =  2.000
  SDA: ingest ion ratio	 sda : in [-] =  0.170
  specific growth rate	 sg [I/day] =  0.156*W[g]A-l. 048*exp (0.069*t[celsius])
  satiation meal size	 sm[g (DW) ] =  not_specif led
  standard V0_2	 so [mg  o2/hr] =  0 . 013 *W [g] Al . 000*exp (0.049*t[celsius])
  time to satiation	 st [minutes]  =  not_specif led
  weight: length	 wl[g(FW)] =  0.002*L[cm]A3.300
  length at first reproduction	 tl_rO[cm] =  33.0
  weight of recruits	 yoy[g(FW)]  =25.0
  spawning interval	 april-may => day (s)  =  31,
  initial standing stock  ...  10.01  [kg(FW)/ha]

ecotoxicological parameters:

  mean lethal activiy	 la[-] =   1.066E-03
                                                                      104

-------
  assimilation efficiency  (fish)
  assimilation efficiency  (inverts) ..
  assimilation efficiency  (plant)
  gill area	 ga [cmA2]  =  4.980*W[g]A0.728
  gastric evacuation	 9e [9 (DW) /day]  =  not_specif led
  inter lame liar distance	 id [cm]  =  0.001*W[g]A0.200
  lamellar density	 Id [lamellae/mm]  =  15.900*W[g]A-0.009
  lamellar length	 11 [cm]  =  0.009*W[g]A0.270
  length of prey	 Ip [cm]  =  0 . 000 + 0 . 250*L [cm]
  maximum filtering	 mf [L/day] =  not_specifled
  maximum ingest ion	 nii[g (DW) /day]  =  not_specif led
  maximum longevity	 mis [day]  =  1826 .
  non-predatory mortality	 nm [1/yr]  =  12.6*W[g]A-0.537
  fraction aqueous	 pa [-]  =  0. 800-0. 940*pl[-]
  fraction lipid	 pi [-]  =  0.080*W[g]A0.000
  reproductive biomass investment	 rbi[-]  =  0.150
  respiratory quotient	 rq [- ]  =  1.000
  routine : standard V0_2	 rt: std [-] =  2.000
  SDA: ingest ion ratio	 sda : in [-] =  0.170
  specific growth rate	 sg [I/day] =  0.007*W[g]A-0. 537*exp (0.069*t[celsius])
  satiation meal size	 sm[g (DW) ] =  not_specif led
  standard V0_2	 so [mg  o2/hr] =  0 . 001 *W [g] Al . 020*exp (0.184*t[celsius])
  time to satiation	 st [minutes]  =  not_specif led
  weight: length	 wl[g(FW)] =  0.030*L[cm]A2.820
  length at first reproduction	 tl_rO[cm] =  15.0
  weight of recruits	 yoy [g (FW) ]  =10.0
  spawning interval	 march-april  =>  day(s)  =  1,
initial conditions
  initial standing stock  ...  19.99  [kg(FW)/ha]

ecotoxicological parameters:

  mean lethal activiy	
                                                                      105

-------
  assimilation efficiency  (fish)	 ae[-]  =  0.890
  assimilation efficiency  (inverts) ... ae [-]  =  0.660
  assimilation efficiency  (plant)	 ae[-]  =  0.440
  gill area	 ga [cmA2]  =  7.320*W[g]A0.820
  gastric evacuation	 9e [9 (DW) /day]  =  not_specif led
  inter lame liar distance	 id [cm] =  0.001*W[g]A0.172
  lamellar density	 Id [lamellae/mm]  =  not_specif led
  lamellar length	 11 [cm] =  0.007*W[g]A0.259
  length of prey	 Ip [cm] =  0 . 000 + 0 . 150*L [cm]
  maximum filtering	 mf [L/day] =  not_specifled
  maximum ingest ion	 nii[g (DW) /day]  =  not_specif led
  maximum longevity	 mis [day]  =  1826 .
  non-predatory mortality	 nm [1/yr]  =  0.570*W[g]A-0.615
  fraction aqueous	 pa [-]  =  0. 781-0. 940*pl[-]
  fraction lipid	 pi [-]  =  0.060*W[g]A0.000
  reproductive biomass investment	 rbi[-] =  0.150
  respiratory quotient	 rq [- ]  =  1.000
  routine : standard V0_2	 rt: std [-] =  2.000
  SDA: ingest ion ratio	 sda : in [- ] =  0.127
  specific growth rate	 sg [I/day] =  0.004*W[g]A-0. 615*exp (0.069*t[celsius])
  satiation meal size	 sm[g (DW) ] =  not_specif led
  standard V0_2	 so [mg  o2/hr] =  0.024*W[g] A0 . 849*exp(0.141*t [celsius] )
  time to satiation	 st [minutes]  =  not_specif led
  weight: length	 wl[g(FW)] =  0.021*L[cm]A3.060
  length at first reproduction	 tl_rO[cm] =  8.000
  weight of recruits	 yoy[g(FW)]  = 5.000
  spawning interval	 april- June  =>  day ( s)  = 47 ,
initial conditions
  initial standing stock  ... 200.29  [kg(FW)/ha]

ecotoxicological parameters:

  mean lethal activiy	 la[-] =   1.066E-03
                                                                      106

-------
  assimilation efficiency  (fish)	
  assimilation efficiency  (inverts)..
  assimilation efficiency  (plant)....
  gill area	 ga [cmA2]  =  7.320*W[g]A0.820
  gastric evacuation	 9e [9 (DW) /day]  =  not_specif led
  inter lame liar distance	 id [cm]  =  0.001*W[g]A0.172
  lamellar density	 Id [lamellae/mm]  =  not_specif led
  lamellar length	 11 [cm]  =  0.007*W[g]A0.259
  length of prey	 Ip [cm]  =  not_specif led
  maximum filtering	 mf [L/day] =  not_specifled
  maximum ingest ion	 nii[g (DW) /day]  =  not_specif led
  maximum longevity	 mis [day]  =  1826 .
  non-predatory mortality	 nm [1/yr]  =  4.34*W[g]A-0.761
  fraction aqueous	 pa [-]  =  0. 781-0. 941*pl[-]
  fraction lipid	 pi [-]  =  0.060*W[g]A0.000
  reproductive biomass investment	 rbi[-]  =  0.150
  respiratory quotient	 rq [- ]  =  1.000
  routine : standard V0_2	 rt: std [-] =  2.000
  SDA: ingest ion ratio	 sda : in [- ] =  0.127
  specific growth rate	 sg [I/day] =  0.009*W[g]A-0. 761*exp (0.069*t[celsius])
  satiation meal size	 sm[g (DW) ] =  not_specif led
  standard V0_2	 so [mg  o2/hr] =  0 . 047 *W [g] A0 . 744*exp (0.044*t[celsius])
  time to satiation	 st [minutes]  =  not_specif led
  weight: length	 wl[g(FW)] =  0.015*L[cm]A3.080
  length at first reproduction	 tl_rO[cm] =  14.0
  weight of recruits	 yoy[g(FW)]  = 5.000
  spawning interval	 may- June  =>  day ( s)  =  62 ,
   age/size
                                                                        -1.
                                                                        -1.
  initial standing stock  . . . 100 . 01  [kg(FW)/ha]

ecotoxicological parameters:

  mean lethal activiy	 la[-] =  1.066E-03
                                                                      107

-------
  assimilation efficiency  (fish)....
  assimilation efficiency  (inverts).
  assimilation efficiency  (plant)...
  gill area	
  gastric evacuation	
  interlamellar distance	
  lamellar density	
  lamellar length	
  length of prey	
  maximum filtering	
  maximum ingestion	
  maximum longevity	
  non-predatory mortality	
  fraction aqueous	
  fraction lipid	
  reproductive biomass investment...
  respiratory quotient	
  routine:standard V0_2	
  SDA:ingestion ratio	
  specific growth rate	
  satiation meal size	
  standard V0_2	
  time to satiation	
  weight:length	
  length at first reproduction	
  weight of recruits	
  spawning interval	
ae [-] = 0.890
ae [-] = 0.660
ae [-] = 0 . 440
ga[cmA2] = 2.606*W[g]A0.883
ge[g(DW)/day] = not_specifled
id [cm] = 0.002*W[g]A0.087
Id [lamellae/mm]  = 28.100*W[g]A-0.073
11 [cm] = 0.019*W[g]A0.294
Ip [cm] = 0.000 + 0.200*L[cm]
mf[L/day]  = not_specifled
mi[g(DW)/day] = not_specifled
mis[day] = 240.
nm[l/yr] = 0 . 740E- 01*W [g] A- 0 . 693
pa[-] = 0.820-1.250*pl [-]
pi [-] = 0.125*W[g] A0.000
rbi[-] = 0.150
rq[-] = 1.000
rt:std[-]  = 2.000
sda:in[-]  = 0.170
sg [I/day]  = 0.000*W[g]A-0. 693*exp (0.069*t[celsius])
sm[g(DW)]  = not_specifled
so[mg o2/hr]  = 0.022*W[g]A0.695*exp(0.055*t[celsius])
st [minutes] = not_specifled
wl[g(FW)]  = 0.018*L[cm]A3.032
tl_rO[cm]  = 3.500
yoy[g(FW)] = 0.025
march-October => day(s)  = 15,  45,  75,  105,  135,  165,  1
initial conditions
  initial standing stock  ...

ecotoxicological parameters:

  mean lethal activiy	 la[-] =   1.066E-03
                                                                      108

-------
summary  of special conditions  during the simulation:
RKINT_RESTART:
RKINT_RESTART:
RKINT RESTART:
RKINT RESTART:
RKINT_RESTART:
RKINT_RESTART:
RKINT RESTART:
RKINT RESTART:
RKINT_RESTART:
RKINT_RESTART:
RKINT RESTART:
RKINT RESTART:
RKINT_RESTART:
RKINT_RESTART:
RKINT RESTART:
BASS_ODESOLVR:
BASS_ODESOLVR:
BASS ODESOLVR:
BASS ODESOLVR:
BASS_ODESOLVR:
BASS_ODESOLVR:
RKINT RESTART:
RKINT RESTART:
RKINT_RESTART:
RKINT_RESTART:
RKINT RESTART:
BASS_ODESOLVR:
BASS_ODESOLVR:
BASS ODESOLVR:
BASS ODESOLVR:
BASS_ODESOLVR:
BASS_ODESOLVR:
BASS ODESOLVR :
BASS ODESOLVR:
BASS_ODESOLVR:
BASS_ODESOLVR:
BASS ODESOLVR:
BASS ODESOLVR:
BASS_ODESOLVR:
BASS_ODESOLVR:
BASS ODESOLVR:
BASS ODESOLVR:
BASS_ODESOLVR:
BASS_ODESOLVR:
BASS ODESOLVR:
BASS ODESOLVR:
RKINT_RESTART:
RKINT_RESTART:
RKINT RESTART:
RKINT RESTART:
RKINT_RESTART:
RKINT_RESTART:
BASS ODESOLVR:
BASS ODESOLVR:
BASS_ODESOLVR:
BASS_ODESOLVR:
BASS ODESOLVR:
BASS ODESOLVR:
BASS_ODESOLVR:
BASS_ODESOLVR:
RKINT RESTART:
RKINT RESTART:
RKINT_RESTART:
RKINT_RESTART:
RKINT RESTART:
BASS ODESOLVR:
BASS_ODESOLVR:
BASS_ODESOLVR:
BASS ODESOLVR:
BASS ODESOLVR:
BASS_ODESOLVR:
euler step
euler step
euler step
euler step
euler step
dn/dt for
euler step
euler step
euler step
euler step
euler step
euler step
dn/dt for
euler step
euler step
species 6
species 2
species 3
species 4
species 1
species 5
euler step
euler step
euler step
euler step
euler step
species 2
species 3
species 4
species 1
species 5
species 2
species 3
species 4
species 1
species 5
species 2
species 3
species 4
species 1
species 5
species 2
species 3
species 4
species 1
species 5
euler step
euler step
euler step
euler step
euler step
dn/dt for
species 3
species 2
species 1
species 3
species 2
species 1
species 4
species 5
euler step
euler step
euler step
euler step
dn/dt for
species 3
species 2
species 1
species 5
species 3
species 2
taken
taken
taken
taken
taken
species
taken
taken
taken
taken
taken
taken
species
taken
taken
species
cohort
cohort
cohort
cohort
cohort
cohort
taken
taken
taken
taken
taken
species
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
taken
taken
taken
taken
taken
species
cohort
cohort
cohort
cohort
cohort
cohort
cohort
cohort
taken
taken
taken
taken
species
cohort
cohort
cohort
cohort
cohort
cohort
at t= 4.50
at t= 4.62
at t= 4.63
at t= 4.63
at t= 4.63
6 cohort 1 approximates a
at t= 7.50
at t= 7.91
at t= 7.98
at t= 7.99
at t= 7.99
at t= 7.99
6 cohort 2 approximates a
at t= 9.50
at t =
4 dies
5 dies
5 dies
5 dies
8 dies
5 dies
at t =
at t =
at t =
at t =
at t =
4 dies
4 dies
4 dies
7 dies
4 dies
3 dies
3 dies
3 dies
6 dies
3 dies
2 dies
2 dies
2 dies
5 dies
2 dies
1 dies
1 dies
1 dies
4 dies
1 dies
at t =
at t =
at t =
at t =
at t =
10 . 0

on day= 12.0
on day=
on day=
on day=
on day=
on day=
350.
350.
350.
350.
350.
18.0
18.0
18 . 0
48.0
48.0





on day= 383.
on day=
on day=
on day=
on day=
on day=
on day
on day=
on day=
on day=
on day=
on day=
on day=
on day=
on day=
on day=
on day=
on day=
on day=
on day=
0.156E+04
0.156E+04
0 . 156E + 04
0 . 156E + 04
0.156E+04
383.
383.
413.
413.
748.
748 .
748.
778.
778.
0 . 111E+04
0 . 111E+04
0.111E+04
0.114E+04
0 . 114E + 04
0 . 148E+04
0.148E+04
0.148E+04
0 . 151E + 04
0 . 151E + 04






due
due
due
due
due
due





due
due
due
due
due
due
due
due
due
due
due
due
due
due
due
due
due
due
due





4 cohort 2 approximates a
1 dies
1 dies
3 dies
1 dies
1 dies
2 dies
1 dies
1 dies
at t =
at t =
at t =
at t =
on day=
on day=
on day=
on day=
on day=
on day=
on day=
on day=
0 . 226E + 04
0 . 226E + 04
0.226E+04
0.226E+04
0 . 183E + 04
0 . 186E + 04
0.187E+04
0.219E+04
0 . 222E+04
0 . 224E+04
0.224E+04
0.226E+04




4 cohort 2 approximat
1 dies
1 dies
1 dies
1 dies
1 dies
1 dies
on day=
on day=
on day=
on day=
on day=
on day=
0.256E+04
0.259E+04
0.260E+04
0 . 262E+04
0 . 292E + 04
0.295E+04
due
due
due
due
due
due
due
due




es a
due
due
due
due
due
due
step function
step function

to
to
to
to
to
to





to
to
to
to
to
to
to
to
to
to
to
to
to
to
to
to
to
to
to
to






exceeding
exceeding
exceeding
exceeding
exceeding
exceeding





exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding





step function
to
to
to
to
to
to
to
to




exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding




step function
to
to
to
to
to
to
exceeding
exceeding
exceeding
exceeding
exceeding
exceeding
for t =
for t =

maximum
maximum
maximum
maximum
maximum
maximum





maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum





for t =
maximum
maximum
maximum
maximum
maximum
maximum
maximum
maximum




for t =
maximum
maximum
maximum
maximum
maximum
maximum
4.63
7.99

longe
longe
longe
longe
longe
longe





longe
longe
longe
longe
longe
longe
longe
longe
longe
longe
longe
longe
longe
longe
longe
longe
longe
longe
longe





solution restarted
solution restarted

vity
vity
vity
vity
vity
vity





vity
vity
vity
vity
vity
vity
vi tv
v _i_ L-y
vity
vity
vity
vity
vity
vity
vity
vity
vity
vity
vity
vity
vity





0.156E+04 solution restarted
longe
longe
longe
longe
longe
longe
longe
longe




0.226
longe
longe
longe
longe
longe
longe
vity
vity
vity
vity
vity
vity
vity
vity




E+04 solution restarted
vity
vity
vity
vity
vity
vity
                                                                  109

-------
BASS_ODESOLVR:  species 4 cohort 1 dies on day= 0.297E+04  due to exceeding  maximum longevity
BASS_ODESOLVR:  species 1 cohort 1 dies on day= 0.299E+04  due to exceeding  maximum longevity
BASS_ODESOLVR:  species 5 cohort 1 dies on day= 0.299E+04  due to exceeding  maximum longevity
BASS_ODESOLVR:  species 3 cohort 1 dies on day= 0.329E+04  due to exceeding  maximum longevity
BASS_ODESOLVR:  species 2 cohort 1 dies on day= 0.332E+04  due to exceeding  maximum longevity
BASS_ODESOLVR:  species 4 cohort 1 dies on day= 0.334E+04  due to exceeding  maximum longevity
BASS_ODESOLVR:  species 1 cohort 1 dies on day= 0.335E+04  due to exceeding  maximum longevity
BASS_ODESOLVR:  species 5 cohort 1 dies on day= 0.335E+04  due to exceeding  maximum longevity
                                                                     110

-------
         total cpu =
 bass_odesolvr cpu =
     bass_dydt cpu =
       dwdtfIx cpu =
       dbdtfIx cpu =
 bass_foodwebl cpu =
 bass_foodwebO cpu =
        ee_adj cpu =
      dry21ive cpu =
R-K integrator cpu =
   load/unload cpu =
  bass_restart cpu =
            mean h =
                                                                  111

-------
APPENDIX F. Example output file (filename.bss) that tabulates annual bioenergetic and contaminant
fluxes.
                                           112

-------
                                          5.541E-03
                                          2.696E-03
                                          1 . 814E-03
                                          1.418E-03
                                          1.194E-03
                                          1 . 051E-03
                                          9 . 519E-04
                                          8.798E-04
                                          8.769E-04
                 [ug/g(FW)]  log(BAF)  log(BMP)
mean body cone.  weighted by cohort biomasses =  0.817
mean body cone.  weighted by cohort densities =  0.671
log mean BAF weighted by cohort biomasses =   6.26
log mean BAF weighted by cohort densities =   6.18
                                                                   113

-------
9.307E-04
1.424E-03
1.586E-03
1.686E-03
1.764E-03
1.819E-03
1.872E-03
1.922E-03
2.028E-03
                                                114

-------
                                                                                155.        88.0
                                                                                263 .        194.
                                                                                347.        279.
                                                                                417.        350.
                                                                                476.        409.
                                                                                45.4        40.0
mean body cone.  weighted by cohort biomasses  =   0.694
mean body cone.  weighted by cohort densities  =   0.615
log mean BAF weighted by cohort biomasses  =    6.19
log mean BAF weighted by cohort densities  =    6.14
   1           9.945E-04
   2           1.309E-03
   3           1.429E-03
   4           1.503E-03
   5           1.548E-03
   6           1.614E-03
                                                                                       76.9        0.00
                                                                                       243.        0.00
                                                                                       395.        0.00
                                                                                       530 .        0.00
                                                                                       644 .        0.00
                                                                                       64.0        0.00
                                                                   115

-------
mean body cone.  weighted by cohort  biomasses =   0.539
mean body cone.  weighted by cohort  densities =   0.467
log mean BAF weighted by cohort  biomasses  =   6.08
log mean BAF weighted by cohort  densities  =   6.02
   1           8.380E-04
   2           1.017E-03
   3           1.071E-03
   4           1.141E-03
   5           1 . 191E-03
   6           1.242E-03
                                                                  116

-------
mean body cone.  weighted  by cohort biomasses =  0.495
mean body cone.  weighted  by cohort densities =  0.482
log mean BAF weighted by  cohort  biomasses =   6.05
log mean BAF weighted by  cohort  densities =   6.04
                                                                  117

-------
                                                                                24.4        14.6
                                                                                52.6        36.7
                                                                                73.2        54.9
                                                                                90.7        70.8
                                                                                106.        84.6
                                                                                22.5        18.2
mean body cone.  weighted by cohort  biomasses =  0.416
mean body cone.  weighted by cohort  densities =  0.370
log mean BAF weighted by cohort  biomasses =   5.97
log mean BAF weighted by cohort  densities =   5.92
                                                                  118

-------
119

-------
                                                                                                              mean
                                                                                                           population
                                                                                                             [#/ha]
         6.853E+03
         5.058E+03
         3.542E+03
         2.698E+03
         2.177E+03
         1.747E+03
         1.483E+03
         1.271E+03
            240.
         2.507E+04
                                                                        1.141E+03
community level fluxes
                                                                 120

-------
                                                                                                                   mean
                                                                                                                population
                                                                                                                  [#/ha]
                                                                             .478E+04
                                                                             . 684E + 03
                                                                               447.
                                                                             .235E+03
                                                                             .564E+03
                                                                               101 .
                                                                             . 144E + 04
         6.110E+04
         3.648E+04
         2.917E+04
         2.707E+04
         1.701E+04
            349.
         1 . 712E + 05
6.717E+03 / 1.600E+03
  2.231E+03 /  147.
   606.      /  20.4
   241 .      /  5.54
community consumption  [g(DW)/ha/yr] of benthos	
community consumption  [g(DW)/ha/yr] of insects	
community consumption  [g(DW)/ha/yr] of periphyton....
community consumption  [g(DW)/ha/yr] of phytoplankton.
community consumption  [g(DW)/ha/yr] of zooplankton...
community consumption  [g(DW)/ha/yr] of fish	
                                             (0.61 of total consumption)
                                             (0.00 of total consumption)
                                             (0.00 of total consumption)
                                             (0.00 of total consumption)
                                                                    121

-------
APPENDIX G. Example output file (filename.plx) that plots the variables requested by the user.
                                           122

-------
123

-------
 I
 a
 >-»
T3


^O

~03

-------
  . ON ON ON ON
ON-—o^ m^r

V V V V V
 a a a a a
 00000
 &DOOOO&DOO
 a EH a a a
o o o o  o

V V V V V
 o o o o o
                                                                        I    I   I   I   I
                                                                                           I   I   I   I   I   I   I
                                                                 OO
                                                                 ON
                                                                                                              1!
                                                                                                                   oo
                                                                                                                   ON
                                                                                                                    oo
                                                                                                                    ON
                                                                                                                    ON
                                                                                                                    ON
                                                                                                                               a
                                                                                                                               o
                                                                                                                    ON
                                                                                                                    ON

-------
 o

'I

 a
 &
 o
 tH


 a
"
a

-------
      V  V  V  V  V
      a  a  a  a a
      00000
      &DOOOO&DOO

      s  a  a  a a
v>    o  o  o  o o
txD   -i-J -)-* -)-*  -i-J -)-*

^    V  V V  V  V
      C/3  C/3  C/3  C/5 C/3




      o  o  o  o o



           !        !    i
           I        I
                                                                                                                                                                                                                       S3

                                                                                                                                                                                                                       >•-»

                                                                                                                                                                                                                      T3
                                                                                                                                                                                                            •  "      &
                                                                                                                                                                                                                       >-.


                                                                                                                                                                                                                       cu

-------
a
o

-------
V V V V V
a a a a a
00000
aoooooaooo
a a a a a
O O O O O
                                                                     I   I   I   I   I
                                                                                       I   I   I   I  I   I   I
                                 oo

                                 o
                                                                                             \

                                                                                           oo
oo
ON
                                                                                                              oo
                                                                                                            _ ON
                                                                                                              ON

                                                                                                            _ ON
                                                                                                              ON

                                                                                                            _ ON
           00
           t4-H
           O
           c/}
           o

           'I

           a
                                                                                                                          a
                                                                                                                          o

-------
 00

 a

 m
 o

'I

 a
 >•-»
T3

,-g

"S

-------
V V V V V
a a a a a
00000
aoooooaooo
rt s a a a
O O O O O
                                                                       oo
                                                                       ON
                                                                       ON
                                                                       ON
                                                                           a   &•
                                                                           PH   s
                                                                       ON
                                                                       ON
                     <•»-]
                     oo
                                            "ouoo  Apoq

-------
a
o

-------
   ^OON ON OOOO

   °~: K~> m i— I ON
   t^' — ON) mm

    V V V V V
    a a a a a
    00000
    &DOOOO&DOO
    s s s s a
CU
oo
 o o o o o

 V V V  V V
O^OONONOO
    o o o o o
                                                                               I   I   I   I   I
                                                                                                  I   I   I   I   I    I   I
                                                                                                                        oo
                                                                                                                        ON
                                                       oo
                                                       oo
                                                                                                                           oo
                                                                                                                           ON
                                                                                                                           ON

                                                                                                                           ON
                                                                                                                    t;
                                                                                                                        ON

                                                                                                                        ON
                                                                                                                                       T3
                                                                                                                                        03
                                                                                                                                        CD
                                                                                                                                       J3
                                                                                                                                       .2
                                                                                                                                        I
O

"ca

-------
 ^
 g
 m
 o
'I
 a

"

-------
    ^oo> o> oooo
    t^' — ON) mm
     V V  V V V
     a a  a a  a
     00000
     &DOOOO&DOO
     s s  s s  a
v>   o o  o o  o
txD  -i-J -)-* -)-* -i-J -)-*
^   V V V  V V
     C/3 C/3  C/3 C/5  C/5

     o o  o o  o

         !       !   i
         I       I
                                                                                                                                                                            ^
                                                                                                                                                                            a
                                                                                                                                                                   •1     fr
                                                                                                                                                                           "

-------
f>

t4-H

 O



 o
 a
 o
 ca



 o

-------
                                                                  i  i
V V V V V
a a a a a
00000
aoooooaooo
a a a a a
rsi rsi rsi rsi rsi
o o o o o
                oo
                ON
co

•M-
OO


T>
                                                    ON
                                                    c-4

                                                    rr>
                                                                  \

                                                                m
                                                                CO

                                                                •M-
                                                                ON
 \

C-")
o

•M-
CO
                                                                uoijBjndod
                                                                                             oo
                                                                                           _ ON
                                                                                             ON
                                                                                           _ ON
                                                                                             ON
                                                                                           _ ON
                                                                                                      fl
                                                                                                      <+*
                                                                                                      o
                                                                                                      t/5
                                                                                                      o

                                                                                                      'I
                                                                                                      a
                                                                                                      a
                                                                                                      o
                                                                                                      "
                                                                                                      c^
                                                                                                      o
                                                                                             CO

                                                                                             c-4
                                                                                             co
                                                                                             co
                                                              co
                                                              co

-------
 a

 rsi
 O
 a
•5-
"

-------
V V  V V V
a a a a a
00000
aoooooaooo
a a a a a
                                                                                                               c3
                                                                                                               a

                                                                                                               "

-------
"S

t4-H
 O

 o
 ca

"3
 c^
 o

-------
                                                                                                I   I   I   I    I   I   I
V  V V V V
a a  a a a
00000
&DOOOO&DOO
a a  a a a
o o o o o
                                                                                      oo
                                                                                      ON
co

•M-
oo


c-4
                                                                                       \
                                                                                     m
                                                                                     CO
  \
CN
CO
                                                     c-4
                                                     c-4
                                                                                                                           oo
                                                                                                                           ON
                                                                                                                           ON
                                                                                                                           ON
                                                                                                                           ON

                                                                                                                           ON
                                                                                                                                       o
                                                                                                                                       'I
                                                                                                                                       a
                                                                                                                                       "
                                                                                                                                       c^
                                                                                                                                       o
                                                                                                                           CO
                                                                                                                           CO
                                                                                                                           co
                                                                                                                           CO
                                                                                  co
                                                                                  CO

-------
"

-------
V V V V V
a a a a a
00000
&DOOOO&DOO
a a a a a
o o o o o
I   I  I   I  I
               I   I  I   I  I   I  I
                                                                                               oo
                                                                                               ON
                                                                                               oo
                                                                                               ON
                                                                                               ON
                                                                                               ON
                                                                                               ON
                                                                                               ON
                                                                                               o

                                                                                               
-------
                                                       00

                                                      c^

                                                       O

                                                       c/}

                                                       O


                                                      'I


                                                       a
                                                       a
                                                       o
l^ -*&*£*

-------
ITV	 '	 ON) ON)

V V V V V
 a  a a a a
 a  a a a a
 o  o o o o
I   I    I   I    I
                     I   I   I   I   I    I   I
                                                                                                                                 oo
                                                                                                                                 ON
                                                                         oo
                                                                         K~>
                                                                                                           in

                                                                                                           O
                                                                                                                                 oo
                                                                                                                                 ON
                                                                                                                                 ON
                                                                                                                                 ON
                                                                                                                                 ON
                                                                                                                                 ON
                                                                                                                                        
                                                                                                                                        a
                                                                                                                                              oo
                                                                                                                                              c^
                                                                                                                                              O
                                                                                                                                              o
                                                                                                                                              "S

-------
 &D
 a
 a
•5

,-g
 1

-------
                                                I  I  I   I  I
                                                             I  I  I  I  I  I  I
«/~) i—I i—I Os) Os)

V V V V V
a a a a a
a a a a a
o o o o o
                                                                             oo
                                                                             ON
                                                                             oo
                                                                             ON
                                                                             ON
                                                                             ON
                                                                                    >

                                                                                    C3
                                                                                    00
                                                                             ON
                                                                             ON
                                                                                     I"
                                                                                    ,-g

                                                                                     g
                                                                             CO
                                                                             CO
                                 CO


                                 •M-
                                 ON


                                 OO
                                                                          co
                                                                          co
                                                      ON
                                                      CO
                                                                CO

                                                                ON)
                                               'ouoo Apoq

-------
                                                     INDEX
chemical parameters
  /chemical	35
  /exposure 	35
  /lethality 	36
  /log_ac 	37
  /log_kbl 	37
  /Iog_kb2 	37
  /log_p 	37
  /melting_point	37
  /metabolism  	37
  /molar_volume  	37
  /molar_weight	38
files
  chemical exposure files (.chm)	44
  chemical property files (.prp)	44, 45
  community files (.cmm)  	44, 45
  fishfiles (.fhs)  	43, 45
  generalized input file 	32
  include files  	32, 43
  management	43
  output file (.bss)	43
  output file (.msg)  	43
  output file (.plx)  	43
  project files (.prj)  	44
fish parameters
  /age_class_duration 	38
  /common_name	38
  /compostional_parameters  	38
  /ecological_parameters	38
  /feeding	39
  /initial_conditions	39
  /morphometric_parameters	39
  /physiological_parameters  	40
  /spawning_period	40
  /species	40
future features  	60
restrictions
  order of commands	45
  specifying chemical names	35
  specifying common names	38
  units recognized by BASS 	41
simulation controls
  /annual_outputs  	33
  /annual_plots  	33
  /biota	33
  /fgets	34
  /header 	 34
  /month_tO 	34
  /nsteps	34
  /simulation_control	34
  /simulation_interval 	34
  /summary_plots	34
  /temperature  	35
  /water_level  	35
simulation options
  dietary exposure via benthos  	36
  dietary exposure via insects 	36
  dietary exposure via periphyton	36
  dietary exposure via phytoplankton	36
  dietary exposure via zooplankton	36
  direct aqueous exposures  	36
  specifying non-fish prey	33,38
  specifying output   	33, 34
  specifying water levels	35
  specifying water temperatures 	35
syntax
  commenting a line	32
  continuing a line	32
  specifying an include file	32
  specifying units	41
  user specified functions  	41
technical support
  reporting comments 	31
  reporting problems	31
  reporting suggestions 	31
                                                        124

-------