EPA/600/A-93/159

       ECOTOXICOLOGICAL PRINCIPLES FOR AVIAN FIELD STUDIES
              USING RADIOTELEMETRY OR REMOTE SENSING
                         Anne Fairbrother
               U.S. Environmental Protection Agency
                Environmental Research Laboratory
                        200 SW 35th Street
                       Corvallis, OR  97333
     In this section, I will provide a wildlife toxicologist's
perspective of avian field studies.  I will focus my remarks on
the type of information needed when conducting studies in field
situations to determine how a specific use of a single pesticide
affects indigenous birds.  I view radiotelemetry as only one
subset of wildlife ecotoxicological studies that could be done,
although it is a powerful tool for determining how free-ranging
animals come in contact with a variety of contaminated
environments and what the short and long-term effects might be.
I will make no attempt in my remarks to limit myself to
discussions of applications of extant technologies.  Rather, I
will discuss the information that we wish to gain and the context
in which it will be used.  By stating the needs of the end-user,
I hope to provide a challenge to telemetry experts to advance the
engineering aspects of radiotelemetry and other remote sensing
technologies.  Hopefully, this will provide us with better tools
for collecting ecologically relevant data in a cost-effective,
real-time fashion.

                            APPROACH
     Put succinctly, the objective of a pesticide field study
usually is to test the null hypothesis that application of a
pesticide will have no effect on indigenous birds.  Of course,
this simple statement leads to many further questions: what is
the ecological significance of "effect"?  what do we mean by "no"
effect? what do we know about dose-response relationships?  is
the "application" a single application or multiple applications?
what is the time period of concern?  I will not attempt to

-------
address broad ecological concerns at this time, but will limit my
comments to direct, biological and toxicological responses of
birds to a pesticide applied under a selected field regime.
Within this context, the wildlife toxicologist is interested in
gathering information in three general areas: (1) what can we
observe about birds' movements and behavior patterns that are
likely to result in their exposure to the chemical; (2) what is
the actual exposure of each individual, and the population, to
the chemical; and  (3) what are the physiological and behavioral
consequences to the individual and population of chemical
exposure (including mortality and reproductive endpoints)?  Once
we  have this information, we can develop simple cause-and-effect
relationships between pesticide application and bird responses.
Given an appropriate study design, we can make further inferences
about how the observed responses vary depending upon the
application rate (dose-response relationships) or the relative
hazards of various compounds (comparative risk), and differences
in the magnitude of the effects on the various species present
(comparative toxicology).  What are examples of the type of data
we collect in order to develop these cause-and-effect
relationships?

Location and Movement:   One vital piece of information is
knowledge of the location of the population of birds of interest
within the study area, in three-dimensional space.  Latitude and
longitude coordinates are needed in order to know when the birds
are in the field to which the pesticide is being applied.
Multiple readings over time are needed to know when the birds are
present and, therefore, have the potential to be exposed to the
chemical.  Spatial movement patterns can also provide information
about what the bird is doing (flying, resting, feeding, nesting)
which, in turn,  provides keys to exposure potential as well as
information about the effect of the pesticide application (did
behaviors change after the spray event in a manner that differs
from control plots?).  Data about movement in the third dimension

-------
 (elevation) can be used to augment information about certain
 behaviors  (flying versus moving on the ground) and to infer
 others  (are canopy-dwelling birds spending too much time on the
 ground?).  Knowing the location of birds in real time is also
 useful  for retrieving carcasses (from pesticide-induced mortality
 or other causes) for quantifying mortality and for diagnostic
 procedures or  for capturing live birds for sampling purposes.
 Special  modifications (e.g., mortality switches, activity
 recorders, physiological-measurement devices) are useful but
 technologically difficult additions.

 Behavior;  Once we know where the birds are located, we then need
 to know  what they are doing there and if their behaviors are
 altered  due to the pesticide application.  In particular, we are
 interested in  determining the effects of pesticide applications
 on those behaviors that will impact population demographics,
 i.e., mortality, natality, and dispersal.  It is important to
 gather information about mortality in a time-dependent fashion.
 In other words, we wish to know when birds die as well as how
 many die.  This will contribute to our ability to link mortality
 to the pesticide application, both by a time association and
 through  various biochemical procedures (e.g., cholinesterase
 activity) that degrade with time after death.  Ultimately, we
 calculate the  survival rate, rather than mortality rate, but
 these data are obviously related.

Reproduction;  Reproduction is another behavior that we typically
measure. Reproduction is, actually, the sum of a series of
 integrated behaviors.  We use the word "reproduction" to
encompass the  entire process from mating behaviors, through
actual fertilization, egg incubation, and raising of young until
they leave the nest.  In strict ecological terms, we should
include the period from fledging (leaving the nest) until the
individual matures and engages in mating behaviors itself.
However, I will leave the discussion of the postfledging time to

-------
the ecologists and focus on the period from initiation of mating
behaviors until the young fledge.

     Mating behaviors in birds can be very complex and frequently
rely on visual cues.  Conspicuousness or condition of plumage is
a factor in mate selection which could be altered by pesticide
exposure (1).  Birds must initiate appropriate behaviors in the
correct sequence and phenology and then must be able to respond
appropriately to behaviors of conspecifics.  This type of
behavior has both learned and innate components so it is not
surprising that neurotropic pesticides have been shown to alter
these patterns (2-4).  Once mating has occurred, egg production
can be reduced due to pesticide exposure (5,6) as can proper
formation of the egg and eggshell (7,8).  Information about
fertility and eggshell quality generally is gathered in
controlled laboratory studies, but it would be extremely useful
to be able to gather similar data in the field to expand our
knowledge about interspecific differences and the interactions of
other environmental stressors (parasites, disease, extreme
weather) with pesticide exposure.  Nesting behaviors (amount of
time spent sitting on eggs, how frequently the eggs are turned,
whether the nest is incubated until term or abandoned early) have
only occasionally been studied in relation to pesticide effects
(9-11)  but provide additional clues about cause-and-effect
relationships relative to the final reproductive output.

Physiological Effects (Biomarkers):  In addition to gathering
data on pesticide effects on survival and reproduction,
ecotoxicological studies would benefit from data concerning
sublethal physiological effects.  This area of study has largely
been ignored to date due to the difficulty of obtaining the
required information.  Examples of questions that could be
addressed within an ecological context include, but certainly are
not limited to: (1)  does exposure to pesticide applications
change the metabolic rates of the birds,  thereby altering the

-------
amount of food and subsequent foraging time needed for survival
or reproductive efforts  (12) ; (2) does exposure to pesticides
make birds more susceptible  to concomitant environmental
stressors such as disease and parasitism  (13); and (3) do
pesticides change hormone production patterns and interfere with
growth and reproduction patterns or other more subtle behaviors
(9)?  Answers to these types of questions would help to make
definitive cause-and-effect  relationships between pesticide
application and subsequent changes in the local populations.
More importantly, they would provide clues to the mechanisms by
which the pesticides exert their effects on the birds.  This
would provide us with stronger predictive models about the
ecotoxicological effects of  pesticides and allow modifications of
application regimes or new pesticide formulations to be made with
a strong scientific basis.   Remote sensing applications for
monitoring physiological measurements will be discussed in more
detail in another chapter.

                            DISCUSSION
     It is very important in field studies to know how much
exposure to the pesticide each individual has received.  Without
this information, cause-and-effect relationships must, therefore,
be based on strong correlative relationships.  There also are
available surrogate measures (biomarkers) of exposure such as
cholinesterase activity in brain and plasma (14)  and chemical
residue on crop and stomach  contents.  For some chemicals, we
have direct exposure measurements through analysis of residues of
parent compounds or breakdown products (e.g., oxones) in various
tissues and excreta.  Tissue residue studies are not ideal,
however, as the current generation of pesticides frequently do
not leave such residues.  Those that do generally require
destructive sampling of the animal and provide information only
about the amount of chemical present at the time of sampling.
Excreta measures of chemical content would be non- destructive
and could be sampled repeatedly through time.  Excreta collected

-------
from nests can be related to a specific individual  (or two), but
this restricts our ability to measure what is occurring in  non-
nesting birds or during the portion of the day when the bird is
not in the nest.  Merely locating the individual coincident with
pesticide application in time and space does not provide a
measure of exposure.  For example, foliage can provide shelter
from exposure while preening activities can increase total
exposure.  Therefore, I challenge you to begin thinking about how
remote sensing technologies could be applied to this problem of
exposure assessment.  From an ecotoxicological point of view,
this is the weakest part of pesticide risk assessment studies.

                             SUMMARY
     In summary, ecotoxicological studies for pesticide risk
assessments strive to develop cause-and-effect relationships
between pesticide application and adverse effects on birds  (both
as individuals and as populations) and to determine the
mechanisms by which the observed effects occur.  In order to
accomplish this, data are collected to determine if the location
of the birds put them into potential contact with the pesticide,
how the pesticide changes behaviors and the physiology of the
animals, and how these changes result in increased mortality and
reduced reproduction.  Radiotelemetry and other remote sensing
technologies can be powerful tools to aid in gathering this data.
Hopefully, the summary presented here will leave you with
thoughts about how to extend the current capabilities of these
tools yet continue to provide information in real-time and  in a
user-friendly fashion.

                           DISCLAIMER
The information in this document has been funded by the U.S.
Environmental Protection Agency.   It has been subjected to Agency
review and approved for publication.

-------
REFERENCES
1.   Hamilton, W.D. and M. Zuk.  1982.  Heritable true fitness
     and bright birds:  A role for parasites?  Science 218:384-
     387.

2.   Forsyth, D.J.  1980.  Effects of dietary fenitrothion on the
     behavior and survival of captive white-throated sparrows.
     In:  I.W. Varty, ed. Environmental surveillance in Mew
     Brunswick, 1978-79.  Effects of spray operations for forest
     protection against spruce budworm.  Committee for
     Environmental Monitoring of Forest Insect Control
     Operations, Dept. For. Res., Univ. New Brunswick,
     Fredericton, pp. 27-28.

3.   Grue, C.E. and B.K. Shipley.  1981.  Interpreting population
     estimates of birds following pesticide applications —
     behavior of male starlings exposed to an organophosphate
     pesticide.  Stud. Avian Biol.  6:292-296.

4.   Busby, D.G., L.M. White and P.A. Pearce.  1990.  Effects of
     aerial spraying of fenitrothion on breeding white-throated
     sparrows.  J. Appl. Icol. 27:743-755.

5.   Stromborg, K.L.  1981.  Reproductive tests of diazinon on
     bobwhite quail.  In: D.W. Lamb and E.E. Kenaga, ed., Avian
     and Mammalian Wildlife Toxicology:  Second Conference.  ASTM
     STP757.  American Society for Testing and Materials,
     Philadelphia, PA  pp. 19-30.

6.   Rattner, B.A., L. Sileo and C.G. Scanes.  1982.  Oviposition
     and the plasma concentration of LH, progesterone and
     corticosterone in bobwhite quail (Colinus virginianus) fed
     parathion.  J, Reprod. Fert.  66:147-155.

-------
7.   Bennett, J.K. and R.S. Bennett.  1990.  Effects of dietary
     methyl parathion on northern bobwhite egg production and
     eggshell quality.  Environ. Toxicol. Chem.  9:1481-1485.

8.   Scott, M.L. J.R. Zimmermann, S. Marinsky, P.A. Mullenhoff,
     G.L. Rumsey and R.W. Rice.  1975.  Effects of PCBs, DDT, and
     mercury compounds upon egg production, hatchability, and
     shell quality in chickens and Japanese quail.  Poultry Sci.
     54:350-368.

9.   Bennett, R.S., B.A. Williams, D.W. Schmedding and J.K.
     Bennett.  1991. Effects of dietary exposure to methyl
     parathion on egg laying and incubation in mallards.
     Environ. Toxicol. Chem. 10:501-507.

10.  White, D.H., C.H. Mitchell and E.G. Hill.  1983.  Parathion
     alters incubation behavior of laughing gulls.  Bull.
     Environ. Contam. Toxicol.  31:93-97.

11.  Busby, D.G., L.M. White and P.A. Pearce.  1990.  Effects of
     areal spraying of fenitrothion nonbreeding white-throated
     sparrow.  J. Appl. Ecol.  27:743-755.

12.  Dominguez, S.E., J.L. Menkel, A. Fairbrother, B.A. Williams,
     and R.W. Tanner.  Effect of 2,4-dinitrophenol on metabolic
     rate of bobwhite quail.  J. Appl. Toxicol. Phamacol. (in
     press).

13.  Porter, W.P., R. Hinsdill, A. Fairbrother.,  L.J. Olson, J.
     Jaeger, T.M. Yuill, S. Bisgaard, W.G. Hunter, and K. Nolan.
     1984.  Toxicant-disease-environment interactions associated
     with suppression of immune system, growth, and reproduction.
     Science.  224:1014-1017.

-------
14.  Mineau, P.   1991.   Choiinesterase-inhibiting Insecticides:
     Their Impact on Wildlife and the Environment.  Elsevier.
     Amsterdam, The Netherlands.  348pp.

-------
                         M     TECHNICAL REPORT DATA
                         (rtcnt ma Instmeiioiu on the re vent he fort eom/rf
 1. REPORT NO,
  EPA/600/A-93/159
                          2.
                            PB93-212793
 a.TITLt AND SUBTITLE
 Ecotoxicological  Principles for  Avian Field
 Studies Using Radiotelemetry or  Remote Sensing
                                                    I. REPORT DATE
                     ». PERFORMING ORGANIZATION CODE
 7. AUTMOR(S)
 Anne  Fairbrother
                                                    I. PERFORMING ORGANIZATION REPORT NO,
•.PERFORMING ORGANIZATION NAME AND ADDRESS
 US  EPA,  ERL-Corvallis,  OR
                                                    1C. PROGRAM ELEMENT MO.
                                                    lireONTRACT/QRANT NO.
 12. tPONSORlNC AGENCY NAME AND ADDRESS
  US Environmental Protection Agency
  Environmental Research Laboratory
  200 SW 35th Street
  Corvallis, OR 97333	
                     13. TYPE OP REPORT AND PERIOD COVERED
                       	 Symposium paper
                     14. SPONSORING AGENCY CODE
                      EPA/600/02
 IB, SUPPLEMENTARY NOTES
 1993.    Pellston  Workshop;
 Asilomar, CA.
Radiotelemetry  for Avian Field Studies,
 IS. ABSTRACT
 In  this section,  I  will provide  a wildlife toxicologist's perspective
 of  avian  field  studies.    I  will  focus  my  remarks  on the type  of
 information  needed  when  conducting  studies  in  field  situations  to
 determine how a  specific use of  a single pesticide affects  indigenous
 birds.     I  view  radiotelemetry  as  only  one  subset  of  wildlife
 ecotoxicologieal  studies that could be done,  although  it  is'  a powerful
 tool  for determining how  free-ranging animals come  in contact  with a
 variety of contaminated environments  and what  the short and long-term
 effects might be.  I will make no attempt in my remarks to limit myself
 to  discussions of applications of extant technologies.  Rather,  I will
 discuss the information that we  wish  to gain and the context in which
 it  will be used.   By  stating the needs  of the end-user,  I hope  to
 provide a  challenge  to telemetry experts  to advance  the engineering
 aspects  of  radiotelemetry and   other  remote  sensing technologies.
 Hopefully,  this  will  provide us with  better  tools  for   collecting
 ecologically relevant data in a  cost-effective,  real-time fashion.
 7.
                            KEY WORDS AND DOCUMENT ANALYSIS
                DESCRIPTORS
         b.IDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
 radiotelemetry, birds,
 remote sensing, pesticides
 S. DISTRIBUTION STATEMENT

   Release to Public
         »» SECURITY. Ct,ASS (T*H Htpertj
          UncTas smear
21. NO. Of PACES
      9
         »0 SECURITY CLASS
          Unclassified
22. PRICE
KPA P»rm §220-1 (»-7J)

-------