United States
Environmental Protection
Agency
Environmental Research
Laboratory
Corvallis, Oregon 97333
EPA/600/R-93/222
November 1993
Research and Development
EPA
HABITAT QUALITY ASSESSMENT OF TWO WETLAND
TREATMENT SYSTEMS IN FLORIDA -- A PILOT STUDY
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Uji^MiJB
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HABITAT QUALITY ASSESSMENT OF TWO WETLAND TREATMENT SYSTEMS
IN FLORIDA--A PILOT STUDY
By:
Lynne S. McAllister
ManTech Environmental Technology, Inc.
USEPA, Environmental Research Laboratory
Corvallis, OR 97333
Project Officer:
Mary E. Kentula
U.S. Environmental Protection Agency
U.S. Environmental Protection Agency
Environmental Research Laboratory
.200 SW 35th Street
Corvallis, OR 97333
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DISCLAIMER
The information in this document has been funded wholly or in part
by the United States Environmental Protection Agency under contract
number 68-C8-0006 to ManTech Environmental Technology, Inc. and 68-
C8-0056 to AScI Corporation, Duluth, MN. It has been subjected to
the Agency's peer and administrative review, and it has been
approved for publication as an EPA document. Mention of trade
names or commercial products does not constitute endorsement pr
recommendation for use.
This document should'be cited as:
McAllister, L.S. 1993. Habitat quality assessment of two wetland
treatment systems in Florida—A pilot study. EPA/600/R-93/222.
U.S. Environmental Protection Agency, Environmental Research
Laboratory, Corvallis, Oregon.
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CONTENTS
DISCLAIMER ii
TABLES . . v
FIGURES vii
ACKNOWLEDGEMENTS ........... .... viii
EXECUTIVE SUMMARY ......... x
INTRODUCTION !
Role of EPA in WTS Operations i
Assessing Wetland Function and Ecological Condition . . 2
Factors Affecting Habitat Quality . 3
Research Objectives ...... 3
METHODS ..... 5
Pilot Study Overview 5
Site Selection and Sampling Schedule 5
Habitat Quality Assessment 6
Florida Study . . . . 7
Site Descriptions 7
Field and Laboratory Methods ...... 9
Site Characterization 11
Vegetation Sampling 11
Invertebrate Sampling and Identification ... 13
Whole Effluent Toxicity Testing 14
Bird Surveys . 15
Site Morphology 17
Acquisition and Use of Existing Data on 'Water
Quality 18
Data Analysis 19
Comparison Data-from the Literature ........ 20
Quality Assurance 21
RESULTS AND DISCUSSION ,......._ . 24
Vegetation . . . . 24
Invertebrates ....... 30
Whole Effluent Toxicity Tests 40
Bird Use 42
Aerial Surveys ......... 42
Following Flights ............ 48
Ground Counts and Ancillary Bird Data 48
Bird Indicator Discussion 50
Site Morphology ........ 52
Water Quality 58
CONCLUSIONS AND RECOMMENDATIONS 66
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LITERATURE CITED .
APPENDIX A. Site Maps and Sampling Points ,
APPENDIX B. Site Contacts and Local Experts Consulted
APPENDIX C.
APPENDIX D.
APPENDIX E.
Invertebrate Biologists and Identification
Keys Used
Water Chemistry of Replicate Samples Used for
Whole Effluent Toxicity Tests
Bird Species Lists Based on Ground Counts and
Inventories
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89
91
94
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TABLES
Table 1. Names, locations, construction dates, and sizes of
WTS sampled in the pilot study 6
Table 2. Pilot study field sampling schedule '. 6
Table 3. Indicators of wetland habitat condition measured
during the 1991 pilot study . 8
Table 4. Cover types'delineated on air photos . . 17
Table 5. The types of water quality data obtained from each'
site 18
Table 6. Percent of the total number of plant species (out
of a total of 63 species) and average percent cover
per square meter (± one standard deviation) '.
comprising each vegetation structural layer at the
Orlando site, 1991 25
Table 7. Frequency of occurrence and average percent cover
per square meter ± standard deviation for each
plant species sampled at the Orlando site, 1991 . . 27
Table 8. Plant species richness at palustrine emergent non-
WTS wetland sites in Georgia and Florida, 1983-
1990 29
Table 9. Aquatic invertebrate taxa and their relative'
abundances at the Orlando and Lakeland .Florida -
sites, 1991 31
Table 10. Number of invertebrates collected per person-hour
in each cell at the Orlando and Lakeland sites . . 36
Table 11. Number of invertebrates collected per person-hour
in each habitat type at the Orlando and Lakeland
sites 36
Table 12. Relative abundances of invertebrate functional
groups, Orlando and Lakeland sites, Florida, 1991 . 38
Table 13. Reproduction and survival of Ceriodaphnia dubia . . 41
Table 14. Measurements on water samples performed by ERL-
Duluth 41
Table 15. Numbers and densities of wading birds detected
during six aerial surveys at the -Orlando and
Lakeland sites, FL, 1991-1992. 44
Table 16. Landscape data acquired from aerial photographs . . 54
Table 17. Summaries of water quality data at the Orlando and
Lakeland sites 59
Table 18. Surface (0.3 m depth) water quality means, ranges,"
and sample sizes from eight Lower Mississippi River
non-WTS abandoned channel and oxbow lakes, 1984 . 61
Table 19. Water quality in created and natural herbaceous
non-WTS marshes near Tampa, Florida, 1988 .... 62
Table 20. Surface water quality means (N=4) and ranges for
Agrico Swamp non-WTS (reclaimed phosphate mine,
marsh and swamp habitat) and an open water area in
a nearby non-WTS natural marsh in Florida, 1982 . 64
Table 21. Surface water quality mean values (depth=0.15-0.29
m) from Nags Head non-WTS marsh ponds, NC, May
1987 64
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Table 22. Surface water quality mean values for non-WTS marsh
sites in the Okefenokee Swamp . .
Table 23. General relationship of data from the WTS studied
in Florida to the range of values reported for non-
WTS in the southeast United States
Table 24. Summary of indicator suitability for assessing the
wildlife habitat quality'of WTS . . .
65
67
68
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FIGURES
Figure 1. Location and general design of the constructed
wetland sites studied in Florida ......... 10
Figure 2. Monthly densities of foraging wading birds at the
WTS and St. Johns sites in central Florida .... 46
Figure 3. Comparison of densities of six foraging wading bird
species at the WTS and St. Johns sites in central
Florida 47
Figure 4. Comparison of non-breeding wading bird densities at
the WTS and St. Johns sites with the results of
similar surveys at subtropical non-WTS wetlands . 49
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ACKNOWLEDGEMENTS
Numerous individuals contributed to the completion of this
research project, and, although I cannot list all of them, I am
greatly appreciative of their efforts. I am especially grateful to
Jane Schuler, who served as half of the field team and worked many
long, difficult days in the field to complete data collection on
schedule, and to JoEllen Honea, who made a substantial contribution
to the final document by conducting extensive literature searches,
developing the computer data base, performing all the data
analyses, and preparing tables for the report.
Richard Olson served as the technical lead and provided
guidance throughout the project. Robert Bastian, Richard Olson,
and Robert Knight conceptualized the research approach and
initiated project planning. I am grateful to Paul Adamus, who
provided literature for supporting material, training in the
Wetland Evaluation Technique, and advice and guidance in the
planning and analysis stages of the project. Arthur Sherman
provided important documentation on sampling and quality assurance
procedures. Cindy Hagley, Debra Taylor, and Bill Sanville at the
EPA Environmental Research Laboratory in Duluth, MN, were very
helpful in planning and preparing for the field season.
Janelle Eskuri received water samples from the field and
conducted whole effluent toxicity tests at EPA's Duluth
Environmental Research Laboratory. Janelle Eskuri, Teresa Norberg-
King, and Lara Anderson prepared documentation of whole effluent
test methods and results, which is incorporated in this report.
Nan Allen at the University of Minnesota-Duluth identified and
enumerated all the invertebrates, prepared documentation, and
provided data for the final report. Ann Hershey conducted the data
quality checks for invertebrate quality assurance. Brehda Huntley
digitized cover types on aerial photographs, conducted all the
Geographic Information System work, and prepared the site location
maps. Robert Gibson and Ted Ernst wrote data analysis programs and
provided data base and software operation support. Kristina Miller
assisted with word processing and editing and prepared Figure 1.
I thank the site managers -- Alan Oyler at the Bureau of
Wastewater/ Orlando, FL, and David Hill with Wastewater Operations
in Lakeland, FL -- for permission to sample at their wastewater
wetlands, for providing existing water quality data, and for their
cooperation throughout the project. I am grateful to Seth Blitch,
Jim Burney, Dr. Bill Dunn, and Mike Mahler for the time they saved
the field crew by identifying pressed plant specimens. Dr. Peter
Frederick and Steven McGehee from the University of Florida in
Gainesville conducted aerial bird surveys and provided data and
supporting documentation for this report. Dave Hill, the Lakeland
site manager, conducted several informal ground bird surveys at the
Lakeland site. Post, Buckley, Schuh, and Jernigan, Inc., provided
species lists of biota at the Orlando site. The time and effort
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spent by numerous individuals who contributed data for use in the
discussion are greatly appreciated.
Bill Ainslie, Robert Knight, and Glenn Guntenspergen provided
technical review for the manuscript. Deborah Coffey and Allan
Deutsch provided quality assurance and editorial reviews,
respectively. All reviewers provided constructive comments and
suggestions for the final draft.
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EXECUTIVE SUMMARY
The use of constructed wetland treatment systems (WTS) for
treating municipal wastewater is increasing in the United States,
but little documentation exists concerning the ability of these
systems to duplicate or sustain wetland functions. A pilot study
was designed primarily to examine methods and the usefulness of
various wetland indicators for assessing wildlife habitat as a
wetland function. The study took place at six WTS sites throughout
the United States. This report focusses on two of those sites,
located in Florida, one near Orlando and one near Lakeland.
Results from the other four sites are presented in two separate
reports, one covering two sites in Mississippi and the other '
covering two sites in the arid West.
Data for vegetation, macroinvertebrate, site morphology, water
quality, and bird use were collected in the field or compiled from
existing data sets. To examine the wildlife habitat function,
various metrics were calculated and assessed for their usefulness
as indicators of wildlife habitat quality. Wildlife habitat
quality was assessed mainly with respect to bird habitat.
Indicator values were compared with ranges of values of the same
indicators from wetlands in the southeastern United States not used
for wastewater treatment (non-WTS). Comparison data from non-WTS
sites were found in the literature. Comparisons were meant to
provide a very preliminary examination of the. wildlife habitat
condition of the two WTS studied by identifying any obvious
deviations from indicator values from non-WTS. In addition to
indicator testing, whole-effluent toxicity tests were conducted on
influent and effluent water samples from each WTS to determine
whether contaminants are entering the WTS and potentially affecting
biota.
Comparisons of habitat indicators for which data from non-WTS
existed showed that indicator values from the two Florida WTS were
generally within the range of values found in non-WTS in the
southeastern U.S. Macroinvertebrate genera richness and bird
species richness were within the upper part of the range or above
the range of values reported for non-WTS. Foraging wading bird
densities were in the lower range of densities calculated from
simultaneous surveys at a nearby non-WTS marsh system. However,
the WTS appear to be important as nesting habitat for wading birds.
Concentrations of various water parameters were at the low to
middle portion of the range of values for non-WTS. Plant species
richness was at the high end of the range of values for non-WTS.
Survival and reproduction of Ceriodaphnia dubia and Pimephales
promelas were not significantly reduced (P<0.05) in whole-effluent
toxicity tests at the two WTS studied.
These preliminary results provide evidence that the habitat •
condition of the two WTS studied is comparable with that of non-WTS
in the same region and suggest that the two WTS provide favorable
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wildlife habitat as an ancillary benefit. Both sites are large,
contain remote areas with a variety of habitats, and support
breeding bird colonies, which is evidence that wastewater treatment
and wildlife habitat enhancement are compatible. .
It is recommended that, for future assessment of wildlife
habitat quality in WTS, indicators from the following categories be
further tested and developed:
• vegetation
• macroinvertebrates
• site morphology
Bird use may be a suitable indicator of the faunal component of;a
WTS, but further consideration should be given to reduction of
sampling effort, collection of more specific metrics, and the
direct relevance of bird use to habitat qoiality. Macroinvertebrate
sampling should be expanded to include benthic macroinvertebrates.
Use of existing water nutrient data and whole-effluent toxicity
tests should have low priority for evaluating and monitoring the
wildlife habitat function of WTS.
Water quality data are difficult to interpret consistently in
terms of wildlife habitat quality. Data quality and comparability
are difficult to assure when using existing data, which are
collected and analyzed differently among sites and are intended for
purposes other than evaluating habitat quality. The collection of
a smaller set of water parameters during the field effort, such as
dissolved oxygen, turbidity, and ammonia nitrogen, might provide
information on system stressors, which can be used to help explain
the status of other indicators.
The whole-effluent toxicity testing methods were'successful
and confidence in the results was high. Single, whole-effluent
tests, however, do not provide time-integrated information about
the effects of specific substances in wastewater on wildlife.
Because documentation of effects is a long-term process and can
become very expensive, toxicity testing should be a separate
activity. It should be done routinely to detect potential
contamination in suspect wetlands. Suspect wetlands could be those
receiving industrial discharges, where contaminants have been found
in the past, or where routine biological monitoring indicates a
potential problem requiring further investigation.
Future studies comparing wildlife habitat quality of- WTS to
non-WTS should include simultaneous measurement of selected
indicators at nearby reference sites (non-WTS) so that confounding
factors are minimized and systematic comparisons can be made
between WTS and non-WTS. For assessing the actual habitat quality
of WTS, however, it is necessary to establish guidelines and
criteria for rating habitat quality to avoid the possibility that
habitat quality assessment is based on comparisons with suboptimal
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wetlands. Data reduction and assessment techniques, possibly
including development of habitat,_ quality indices, should be
explored in future studies so that various indicators can be
aggregated and conclusions about overall habitat quality can be
derived from more rigorous analyses.
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INTRODUCTION
Freshwater, brackish, and saltwater wetlands often serve as
natural water purifiers for wastewater from point and non-point
sources. Wetlands designed specifically for treating water are
often built to take advantage of this purifying function. Recent
declines in federal funds allocated to municipal pollution control,
as well as water pollution control mandates under the Clean Water
Act for both municipal and industrial point source dischargers,
have led to an increase in the construction of wetlands for
treating wastewater. Municipal constructed wetland treatment
systems (hereafter referred to as WTS) are engineered complexes of
saturated substrates, emergent and submergent vegetation, animal
life, and water that simulate natural wetlands for the primary
purpose of wastewater treatment (Hammer and Bastian 1989). These
systems receive partially treated wastewater and are designed to
reduce biochemical oxygen demand (BOD), nutrient and metals con-
centrations, and levels of other pollutants (Kadlec and Kadlec
1979, Nixon and Lee 1986) . WTS are used for a variety of purposes,
including treatment of municipal and home wastewater (US EPA 1988a,
Conway and Murtha 1989), acid mine drainage (Brodie et al. 19,89) ,
landfill and industrial wastewater (Staubitz et al. 1989), nonpoint
source pollution (Dickerman et al. 1985, Costello 1989'), and urban
stormwater (King County 1986).
Wetland treatment systems fall into two general categories:
1) vegetated submerged-bed wetlands, in which water moves through
a soil or rock substrate in the bed of the system where it makes
contact with plant roots; and 2) free water surface wetlands, in
which most of the water flow is above ground over saturated soils
(US EPA 1988a, Reed et al. 1988) . Free water surface wetlands were
the focus of this study because they are designed to replicate
natural wetland systems. They are usually constructed with several
sections, or cells, separated by weirs which can be used to control
water_ level and flow rate. Water is treated primarily through
assimilation of nutrients and other pollutants by microorganisms in
the substrate and attached to plant roots. Plant species selected
for these systems often contain large amounts of aerenchyma and are
efficient in translocating oxygen from the atmosphere to their root
zones, which facilitates respiration by microorganisms.
Role of EPA in WTS Operations
One objective of the Clean Water Act is to restore and
maintain the physical, chemical, and biological integrity of waters
of the United States through the elimination of discharges of
pollutants (Yocum et al. 1989). Under the Clean Water Act, most
natural wetlands are considered to be waters of the United States.
The EPA is responsible for implementing the Clean Water Act and
associated regulations on the discharge of wastewaters to the
Nation's waters. Discharges must meet requirements set in a
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National Pollutant Discharge Elimination System (NPDES) permit
issued by EPA or a delegated state (Da.vis and Montgomery 1987) .
Presently, WTS usually are not considered "waters of the United
States" (Bastian et al. 1989) and therefore discharges to these
systems are not regulated by EPA under the Clean Water Act.
However, discharges from WTS to waters of the United States must
meet NPDES requirements. Therefore, EPA must evaluate the
capability of WTS to meet water quality standards under Sections
401 and 402 of the Clean Water Act. Water monitoring programs are
in place at WTS which discharge to waters of the U.S.
In addition to its regulatory role, the' EPA is interested in
the ancillary functions of WTS, including wildlife habitat. WTS
attract wildlife and therefore cannot be considered isolated
operations. Habitat quality concerns Include potential risks to
wildlife by substances entering in wastewater (Davis and Montgomery
1987). Because many wildlife species are mobile, conditions in WTS
can influence wildlife health and use in a network of wetlands,
including wetlands that are waters of the U.S. It is therefore
important for the EPA to develop methods for assessing and
monitoring the condition of WTS and to coordinate these methods
with methods used for natural, restored, and created wetlands. ;
Assessing Wetland Function and Ecological Condition
While WTS can duplicate structural aspects of some natural
wetlands, little is known about the replication of wetland
functions. The functions that wetlands perform depend upon wetland
type, location, the local geology, topography, and hydrology, and
other watershed characteristics. Typical wetland functions
include: wildlife habitat, recreation, nutrient and pollutant
assimilation and retention, detritus and dissolved nutrient and
organic matter production, reduction of downstream sedimentation,
floodwater retention, and groundwater recharge. With the exception
of nutrient removal, wetland functions are normally considered
"ancillary", or supplemental in WTS because these systems are
designed primarily for wastewater treatment and secondarily for
other purposes.
Wetland treatment systems can and do provide various ancillary
functions, but concerns exist about potential contamination and
effects on wetland ecological condition caused by additions of
wastewater (Godfrey et al. 1985, US EPA 1984, Mudroch and
Capobianco 1979). The ecological condition, or "health" of a
wetland refers to its biological integrity, sustainability, and
ability to serve multiple functions. A "healthy" wetland exhibits
structures and functions necessary to sustain itself and is free of
most known stressors or problems (Rapport 1989, Schaeffer et al.
1988) .
Ecological condition can be assessed and monitored on the
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basis of various wetland attributes, or indicators. Indicators are
characteristics of the environment that, when measured, quantify a
habitat characteristic, magnitude of stress, degree of exposure to
the stressor, or degree of ecological response to the exposure
(Hunsaker and Carpenter 1990). Indicators can be measured or
quantified through field sampling, remote sensing, or analysis of
existing data. Many potentially valuable indicators exist for
assessing and monitoring a resource, but it is most desirable to
identify a suite of indicators that best describes the overall
condition of the resource.
Factors Affecting Habitat Quality
Wetland treatment systems often provide wildlife habitat as an
ancillary function (Piest and Sowls 1985, Sather 1989). Nutrient
additions usually increase net primary productivity (Guntenspergen
and Stearns 1985) and promote waterfowl production (Cedarquist
1979) . Alternatively, extremely high nutrient concentrations or
loadings and lack of variation in water depth can encourage estab-
lishment of macrophyte monocultures with lower habitat value
(Fetter et al. 1978, Kadlec and Bevis 1990). Nutrient enrichment
in eutrophic and hypereutrophic systems can cause algal blooms,
resulting in highly variable dissolved oxygen concentrations and
reduced light penetration. The latter condition greatly affects
plant species diversity and distribution, particularly of
submergent species. Species composition and extent of aquatic
macrophytes can affect the abundance and diversity of aquatic
invertebrates (Dvorak and Best 1982, Reid 1985, Voights 1976);
subsequently, plant-invertebrate associations influence use by
waterfowl (Krull 1970, Teels et al. 1976). Wetland morphology,
location, and hydrologic regime also interact to influence the
quality of habitat that develops.
Wildlife using WTS can be exposed to pollutants. Although
municipal discharges to wetlands are regulated by state and federal
agencies, and industrial discharges are not recommended for WTS,
occasional exceptions and/or violations of regulations can result
in at least temporary discharge of potentially harmful substances
to WTS. This creates potential for some organisms to be affected
through exposure, ingestion, or bioaccumulation of substances.
Detailed information about wetland animal communities in WTS is
lacking in the literature (Brennan 1985).
Research Objectives
There have been no comprehensive, large-scale studies of the
ecological condition and wildlife use of WTS (Bastian, personal
.communication, U.S. EPA, Washington, DC). A pilot study was
designed as an exploratory effort for examining research methods,
indicators, logistics, and capabilities for conducting preliminary
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assessments of wildlife habitat as an ancillary function of WTS.
The study was not intended to provide probability samples to
statistically characterize a defined population of WTS. However,
many of the conclusions about wildlife habitat quality drawn from
the data collected in this 'study can be used to design future
research.
Because WTS are not considered waters of the U.S., the issue
of jurisdiction during and after the operational phase is complex.
Results of this study should not be used to make inferences
regarding jurisdiction of WTS or to provide support for mitigation
credit for WTS under Section 404. There "is still inadequate
knowledge of the ability of WTS to repleice wetland functions.
The objectives of the study were:
• to assess the usefulness of methods and indicators for
evaluating the wildlife habitat qusility of WTS,
• to identify any major differences in values of wildlife
habitat indicators in WTS and non-WTS, and
• to provide baseline data and identify approaches for a more
focussed follow-up project that will provide specific
information for developing measures of the wildlife habitat
quality of WTS.
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METHODS
The pilot study included sampling and habitat quality
assessment at six WTS in the United States (Table 1) . The same
general framework and study design was used for conducting work at
all sites. Pilot study results, however, are reported in three
separate EPA documents, each dealing with two sites: 1) Florida
sites (this report); 2) Mississippi sites (McAllister 1992); and 3)
western sites (McAllister 1993).
Pilot Study Overview
This section discusses activities concerning the design of the
overall pilot study, including selection of the six WTS sites
studied, habitat quality assessment techniques, the indicators
chosen for measurement, and the field sampling schedule.
Site Selection and Sampling Schedule
Six free water surface municipal WTS in-the United States were
chosen for sampling in 1991. The sites were chosen based on the
following criteria:
• location in the Southeast or in the arid and semi-
arid West, so that WTS in two different geographic
and climatic regions of the country could be
studied,
• representing a range of sizes,
• representing a range of ages and in operation for
at least one year,
• availability of water quality data for use in
indicator analysis,
• permission to use the site, and
• interest in collaboration by site operators and
"other groups. . . -
Field data were collected in July and August 1991 according to the
schedule shown in Table 2.
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Table 1. Names, locations, construction dates, and sizes of WTS
sampled in the pilot study.
Site name Location Year built Size(ha)
Orlando Orlando, FL 1987 486.00 .
Lakeland Lakeland, FL 1987 498.00 ;
Collins Collins, MS 1987 4.47
Ocean Springs Ocean Springs, MS 1990 9.28
Show Low Show Low, AZ ' 1980 284.00
Incline Village Incline Village, NV 1985 198.00
Table 2. Pilot study field sampling schedule.
Sampling location Dates
Incline Village, NV July 8-12
Show Low, AZ July 19-23
Ocean Springs, MS July 30-Aug. 3
Collins, MS Aug. 6-9
Orlando, FL Aug. 14-19
Lakeland, FL Aug. 19-23
Habitat Quality Assessment
Habitat quality was assessed mainly with respect to birds
because birds were used as a faunal indicator in the project. More
species of birds than of mammals are dependent on wetlands, thus
more literature exists on wetland habitat requirements of birds.
Many of the habitat components necessary for birds are also
beneficial to mammals (e.g., cover extent and diversity, food
resources, a landscape habitat mosaic).
Two general assessment techniques were evaluated in the pilot
study for use in assessing Wildlife habitat quality as an ancillary
benefit. One technique was the measurement of selected indicators
of habitat quality. A suite of indicators was chosen for
measurement at the WTS sampled. Indicators were selected based on
the likelihood that
• sample collection, processing, and labor costs would not
exceed budget constraints,
• data collection would not exceed available human
resources,
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• adequate data could be collected within the 4-5 days
spent at each site,
• chosen indicators could be used to effectively
characterize and evaluate wildlife habitat quality,
• required sampling would minimize environmental impact,
and
• variability of collected data would be low within a site
and consistent among sites.
Some of these criteria were unknown for some of the candidate
indicators (e.g., ability of indicators to characterize and
evaluate wildlife habitat quality, data variability, adequate
number of data) . One of the objectives of the study, however, was
to test the indicators by determining their ease of "measurement and
the quality of data obtained in relation to logistics involved in
collecting them. Indicators chosen for testing are listed in Table
3. They are grouped into one of three data source categories:
• data collected in the field
• data acquired from aerial photographs
• existing data sets and records kept for each site
The other assessment technique, performed at only half the
sites, was the use of the Wetland Evaluation Technique (WET)
(Adamus et al. 1987), a rapid assessment technique for evaluating
wetland ancillary values, including wildlife habitat. WET was
given low priority in the pilot study, and limited time at some of
the larger sites prevented its completion. It was therefore not
conducted at either of the Florida sites. Its, use in WTS is
discussed in more detail by McAllister (1992, 1993') .
Florida Study
_The remainder of this document addresses only the Florida
portion of the pilot study. This section contains- site
descriptions, and field and laboratory methods.
Site Descriptions
The general locations and designs of the Florida sites are
shown in Figure 1. Additional site details are shown on site maps
in Appendix A. In addition, a management/operations contact is
given for each site in Appendix B. Each site is briefly described
below.
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Table 3. Indicators of wetland habitat condition measured during
the 1991 pilot study.
Ecological Component Indicators
A. Indicators measured in the field:
Vegetation -Species composition and percent
coverage
-Structural diversity and dominance
-Species dominance
-Species richness :
Invertebrates -Species and functional group
composition and relative abundance
-Genera richness
Water -Whole effluent toxicity tests on
inflow and outflow
Birds -Density ;
-Species richness
B. Indicators taken from aerial photographs:
Site morphology -Wetland area
-Distance of land/water interface
per hectare •
-Distance of edge between selected
cover types per hectare •
-Ratio of open water area to area
covered by vegetation <-
-Relative coverage of selected
vegetation types
C. Indicators obtained from existing data sets:
Water -pH
-Dissolved oxygen
-Biochemical oxygen demand
-Total suspended solids
-Ammonia nitrogen
-Total Kjeldahl nitrogen
-Total phosphorus
-Fecal coliform bacteria
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Orlando, FL The 494-ha WTS was constructed in 1987 in an active
cattle pasture to provide additional nutrient removal for. tertiary
treated' domestic wastewater 'from the City of Orlando's Iron Bridge
Regional Water Pollution Control Facility. The nutrient
sensitivity of Florida's rivers and lakes necessitates advanced
tertiary treatment before water can be discharged into the St.
John's River, .approximately 1.3 km away. The project is one of the
first large-scale artificial wetlands designed to treat domestic
wastewater as well as to provide wildlife habitat. The WTS has 17
cells and a lake. The design flow is 75,700 m3/day (20 mgd), which
results in an average residence time of water in the WTS of 30
days. Most of the necessary water treatment is accomplished in
cells 1-12, which are composed primarily of bulrush and cattail.
Cells 13-17, which are designed and managed to provide habitat
diversity for wildlife, are composed of communities of mixed
vegetation, including palm and cypress swamps. In the off-hunting
season, the site serves as a recreational park for area residents.
Post, Buckley, Schuh, and Jernigan, a consultant for the city of
Orlando, regularly collects water, flora, and fauna data and
conducts monitoring and management at the site.
Lakeland, FL This WTS receives secondary treated water and
provides tertiary treatment for the city of Lakeland, FL. The
treatment plant in Lakeland primarily handles domestic wastewater
but also _receives some wastes from packaging and food industries,
photo finishing, and linen services (Dave Hill, personal
communication, Wastewater Operations, Lakeland, FL). The WTS has
a_design flow of 86,400 m3/day (14 mgd), and a design detention
time of 80-100 days (Dave Hill, personal communication, Wastewater
Operations, Lakeland, FL) . The Lakeland plant treats'domestic and
industrial wastewater before discharging water to the WTS. The
site is located 97 km west of Orlando on an old phosphate mine.
Built in 1987, the WTS is comprised of seven cells and'covers 498
ha, making it the largest free water surface WTS in the U.S. at the
time of construction. It supports herbaceous wetland plants,
primarily cattails, and very dense shrub communities, which have
colonized the site since shortly after its construction. The
sediment is a very fine silt or clay that is settling out slowly,
so the substrate is soft and unstable, and the bottom contour is
irregular. Many areas of the site, particularly in cells 4-7, are
deep and more characteristic of lakes than of palustrine wetlands.
Cell 6, the deepest cell, is over .>14 m deep. This and other cells
are possibly receiving groundwater. Islands in cell 5 support
large wading bird rookeries. Water monitoring data are collected
routinely at the site.
Field and Laboratory Methods
This section describes the methods for all activities
conducted during the field season in July and August, 1991 (Table
2), as well as laboratory analysis of water and invertebrate
-------
N
ORLANDO
LAKELAND
Figure 1. Location and general design of the constructed wetland
sites studied in Florida. The cells of each WTS are
numbered for reference.
10
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samples. The activities described are: site characterization;
vegetation, invertebrate, water, and bird sampling; and
invertebrate and water laboratory analyses. Indicators measured in
the field or calculated are listed in Table 3.
Site Characterization
Site characterization included gathering information about the
layout of the site and the distribution of major vegetation types,
photographing the major habitat types on the site, and recording
wildlife species observed during the several days spent sampling
the site.
The first task at each site was to drive and/or walk around
the entire site and along all interconnecting dikes to roughly map
the locations of major vegetation types, open water, bare soil,
roads, and rookeries visible from the dikes. Cover type boundaries
were delineated on available site maps. This exercise provided
cover maps of dominant plant species to verify air photo
interpretation and to ensure that vegetation transects could be
sited representatively.
Vegetation Sampling
Because of the dense shrub community and unstable substrate at
the Lakeland site, vegetation was sampled only at the Orlando site.
Vegetation sampling included transect establishment through major
cover types, cover estimation at points along transects, plant
specimen preservation, and identification of unknown plants by
local botanists. Collected data were used to calculate indicators
listed in Table 3. At the Lakeland site, effort was'devoted to
mapping plant communities as ground truth for aerial photo
interpretation.
•Transect establishment
_Transect placement required a great deal of judgement based on
the initial site survey and the distribution of vegetation types.
In general, transects were placed:
• through the major vegetation strata at the site. Major
strata were defined for this study as: emergent-Typha,
emergent -Scirpus, emergent-other dominant, emergent-mixed
species, submerged, floating-leaved, scrub/shrub,
forested, and open water; and
• to intersect a diversity of dominant plant species
represented within each'stratum.
11 .
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Wetland area, accessibility to vegetation sample points, and
configuration and size of plant communities were factors considered
when determining the length of individual! transects and the. number
of sample points along transects.
Due to the large size of the Orlando WTS, sampling was not
conducted in all cells. Cells 1-10 were dominated by a relatively
uniform cover of either Typha spp. or Scirpus spp. Therefore one
transect was established in each of those communities -- cell 2 aiid
cell 9, respectively -- to characterize percent cover. In
addition, one transect was established in the mixed community in
cell 13, and one transect was established in the forested community
of cell 16 to characterize a variety of plant species and strata
more typical of cells 13-17. A greater number of points were
sampled in the mixed community than in the Typha and Scirpus
communities of cells 2 and 9 to characterize a greater variety of
plant communities and structures (Appendix A). Transects began at
the wetland edge (i.e., where hydrophytic plants or hydric soils
were present) and extended into the wetland. Upland habitats were
not sampled. Sixty-five points were sampled at the Orlando WTS.
Sampling points were spaced 20 m apart eilong all transects. Cells
11, 12, and 15 to the south of the entraince road were not sampled.
Cover estimation
One, two, or three plots were established at each sample point
along transects, depending upon the structural types of vegetation
present. A 1-m2 quadrat was used for sampling herbaceous
vegetation (emergent, submergent, floating-leaved); a 5-m2 quadrat
was used for shrubs (0.5-6.0 m tall, including tree seedlings and
saplings) ; and a 10 m radius circular plot was used, to sample trees
(>12.5 cm diameter at breast height and >_6 m tall) .
Scientific names were recorded for all species found within
each plot, and absolute percent cover of each species was estimated
as close as possible to the following categories: 1%, 5%, 10%, 20%,
35%, 50%, 65%, 80%, 90%, 99%, or 100%. The estimate was made of
the undisturbed canopy of all plant species that fell within the
plot, even if plants were rooted outside of the plot. No effort
was made to adjust for discontinuities in the canopy of species
with open growth habits or in the coverage of small float ing-leaved
species such as Lemna and Wolffia. Because species can overlap
each other, the sum of cover percentages often exceeded 100%. The
estimates included only vegetation that was visible. The percent
cover of submerged species were therefore often not recorded, but
submerged vegetation was noted as being present. Both members of
the field crew discussed cover percentages for each species in each
plot and together agreed on an estimate. Unknown plants were
collected, coded, and pressed for later identification.
Professional botanists who identified unknown plants are listed In
Appendix B.
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For herbaceous plots (1-m2) , the strata was the cover type
that predominated in the plp;t.. Strata types were emergent-Typha,
emergent-Scirpus, emergent-other dominant, emergent-mixed species,
submerged, floating-leaved, and open water. The strata type was
scrub/shrub for 5-m2 plots and forested for 10 m radius circular
plots. In addition, each species observed in plots was assigned to
one of the following structural types (or layers):
submergent
emergent (or herbaceous)
scrub/shrub
forested
floating-leaved
dead (standing or fallen).
Invertebrate Sampling and Identification
A semi-quantitative dip-net sampling method was used for
collecting invertebrates. Collection techniques were qualitative,
but the picking of invertebrates from nets was timed so that the
numbers of invertebrates could be expressed per unit time and in
relative abundances. This approach has been used in various forms
to make general assessments and to determine relative abundance of
the taxa of aquatic insects (e.g., Plafkin et al. 1989, Merritt and
Cummins 1984, Tucker 1958, Smith et al. 1987, Brooks and Hughes
1988, Jeffries 1989, Voights 1976). The semi-quantitative method
was chosen because the objective of the pilot study was to
determine richness and. relative abundance of taxa found at the time
of sampling. Study objectives did not require statistical
comparisons among sites or sampling points, so quantitative samples
per unit area were not necessary. The semi-quantitative net method
requires less time, labor, and equipment and has been shown to
sample more taxa than quantitative methods such as Hester-Dendy
samplers and sediment cores (Peter M. Wallace, personal
communication, Environmental Consultants, Gainesville, FL).
_Sample points were distributed among the wetland cells and
within major vegetation strata. Locations of invertebrate sampling
points are shown on the site maps in Appendix A. Because both WTS
were large, not all wetland cell/habitat combinations were sampled.
Where several adjacent cells supported similar plant communities,
a subsample of cells and habitats was arbitrarily selected for
sampling.
At the Orlando site, invertebrates were sampled in only half
of the first ten cells because the plant communities of those cells
were very similar. Samples were also collected from cells 13, 14,
and 17 to characterize invertebrates in the mixed plant and
forested communities. Two field crew members sampled each
cell/habitat simultaneously. Effort was divided between the two
people by dividing areas to be sampled in half. At the Lakeland
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site, invertebrates were sampled in all cells except cell 6. In
all except cell 1, invertebrates were sampled from a raft because
the substrate was too unstable to walk on and the water was usually
over 5 feet deep. One person netted invertebrates, primarily in
the upper water column around plant stems, while the other person
steadied the raft.
Sweeps were made with a rectangular kick net (#30 'mesh) along
the wetland bottom (Orlando site only), around plant stems, and
along the surface where floating-leaved species were present.
After several sweeps with a kick net in. one habitat, contents of
the nets were placed into enamel pans, a timer was started, and
invertebrates were picked out by hand or with forceps. Specimens
were placed into 95% ethyl alcohol preservative in prelabelled
glass jars. When all individuals had been picked from the sample,
the timer was stopped while a new net sample was obtained. The two
field crew members picked invertebrates for a total of 30 minutes,
which resulted in a 1-hour collection period for each sampling
point.
Invertebrates were shipped to the University of Minnesota-
Duluth for identification (Appendix C) . Collection jars were
emptied into a glass pan and sorted by life stage and order/family.
Individuals were identified to family arid genus using a microscope
and the taxonomic keys listed in Appendix C. Each genus was placed
in one of the following functional groups: shredder, collector,
predator, scraper, and piercer (Merritt and Cummins 1984). In some
cases, Merritt and Cummins list two functional groups for a genus
so both were specified when data were recorded. All functional
groups except piercers are defined by Vannote and others (1980).
Merritt & Cummins (1984) define piercers as insects that suck
unrecognizable fluids from vascular hydrophytes. Functional groups
were not assigned to terrestrial invertebrates or to imm'atures that
could be identified only to family.
Invertebrates of the class Oligochaeta (aquatic earthworms)
were keyed only to family based on external characteristics and
were counted by totaling the terminal ends collected and dividing
by two. Functional groups were not assigned to Oligochaeta.
Chironomids were divided into groups based on external feature^.
A few individuals from each group were then mounted on microscope
slides for identification to genus. The total count for each genus
was the total in the group. Partial invertebrates were counted if
a head was present with the exception of snails for which whole
shells were counted regardless of whether the animal was present.
Whole Effluent Toxicity Testing
One-liter water grab samples were collected at the inflow,
where water had not yet received wetland treatment, and. at the
outflow, after water had undergone advanced treatment in the WTS
14
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(collection locations are shown in Appendix A) . The purpose of the
two sampling locations was ,i;6 determine whether toxic substances
were entering the WTS and, it so, whether they were being removed
from the water during residence in the WTS. Samples were shipped
in ice to the Environmental Research Laboratory in Duluth (ERL-
Duluth). Samples arrived at the laboratory for acute and chronic
whole effluent toxicity tests the day after they were collected (<.
36 hours). .The purpose of the tests was to identify sites where
toxicity might be a problem so that more intensive studies could be
done in the future if necessary.
Standard laboratory operating procedures of the National
Effluent Toxicity Assessment Center (ERL-Duluth) (US EPA 1988b)
were used for making routine measures and for conducting toxicity
tests. At ERL-Duluth, water samples underwent the following
routine measurements for whole effluent toxicity testing:
alkalinity, hardness, ammonia, total residual chlorine, and
temperature.
Chronic toxicity tests were conducted over a period of 7 days
with renewal of test solutions every other day. Lake Superior
water was used for a performance control, and undiluted influent
and effluent samples from the Florida WTS sites were tested.
Aliguots of each sample were slowly warmed to 25° C prior to use.
Ceriodaphnia dubia (water flea) six hours old or. less were obtained
from the ERL-Duluth culture. Ten replicates for each sample and
the control were used. Each replicate contained one organism in 15
ml of test solution in a 1-oz. polystyrene plastic cup. Block
randomization was used. The Ceriodaphnia dubia were fed daily with
100 uL of a yeast-cerophyll-trout food mixture and 100 uL of algae,
Selenastrum capricornutum. Initial measurements of pH,
temperature, conductivity, and dissolved oxygen were taken after
each sample was warmed and prior to each renewal. The'mean young
produced per original female and the mean percent survival were
recorded after seven days.
Fathead minnows (Pimephales promelas) 24 hours old or less
were obtained from the ERL-Duluth culture for acute tests. Two
replicates for each sample and the control (Lake Superior water)
were used. Each replicate contained ten fish in 15 ml of test
solution in a 1-oz. polystyrene plastic cup. The test was not
renewed and the fish were not fed. The mean number of surviving
minnows was determined after 96 hours and expressed as a percentage
of the total at the beginning of the" test. Fathead minnow tests
were not conducted on the Lakeland water samples.
Bird Surveys
Data on waterbird use of the wetlands for foraging' and nesting
were acquired from surveyors from the University of Florida in
Gainesville (Appendix B) . Low altitude (60 m) aerial surveys were
15
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conducted once per month in October arid December, 1991, and in
February, March, April, and May, 1992. In addition, surveys were
conducted at some of the relatively undisturbed natural wetlands in
the St. Johns River marshes just to the east of the Orlando site to
look for differences in waterbird use between the WTS and the
natural wetlands. No similar natural wetlands were located near
the Lakeland site for making comparisons. Surveys were scheduled
to provide information about seasonal variation in waterbird use of
the WTS. Surveys were conducted between 0700 and 1200 EST as close
to the 15th of each month as weather and aircraft availability
would permit. The Orlando site was always surveyed first, the St.
Johns marshes second, and the Lakeland site last.
The number of foraging and nesting wading birds seen at each
WTS was estimated on each survey flight. Surveys were conducted on
east-west transects to provide 100% coverage of the sites.
Transect boundaries were pre-determined to avoid double counting of
birds on successive transect passes. Two observers conducted
surveys from a Cessna 172 aircraft at an altitude of 200 feet.
Observers sat on opposite sides of the aircraft and counted birds
on their side. Each observer tallied the number of each wading
bird species seen on each transect, and tallies from both observers
were summed over all transects. Large flocks of mixed species were
circled and counted several times to confirm the numbers before
continuing on the transect. Waterbirds in colonies at the WTS were
counted on March, April, and May aerial surveys. . Counts were
confirmed by repeatedly counting nesting birds at both low and high
altitudes. Wading birds that could not be distinguished to species
from flying altitude (e.g., snowy egrets and immature little blue
herons) were lumped together as unidentified small white herons,
following the methods of Hoffman et al. (1990).
In addition to aerial surveys, wading birds were followed on
foraging flights from colonies at the Lakeland and Orlando WTS
sites to examine the relative importance of the WTS to breeding
wading birds. Randomly-selected breeding birds from colonies were
followed to the first site at which they landed and foraged.
Following was done by one observer and the pilot in a Cessna 172.
Locations of foraging sites were noted using U.S. Geological Survey
topographic maps and, on most flights, a Trimble TransPac Global
Positioning System with a 100-m accuracy. Following flights
concentrated on white ibises, great egrets, and snowy egrets.
Dave Hill, the site manager at Lakeland, conducted five ground
counts at the Lakeland site between November 1991 and June 1992,
Counts were made during the same period as the aerial surveys.
Although only one of the counts was done on the same day as an
aerial count, the ground counts provide a cursory field
verification of aerial counts of breeding wading birds, as well 'as
information on the presence of species not visible from the air.
All individuals of each bird species weire counted between 0900 and
1200 hours from fixed survey points along the dikes in ten
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designated areas, comprising approximately 15% of the total site
area. The breeding islands :in cell "5 were given the most complete
areal coverage. These areas were also surveyed on every date,
whereas. other areas were surveyed on only two or three of the
dates.
Site Morphology
Color infrared photographs were taken of each site in summer
1991 by a local aerial survey company (Appendix B) . Photos
overlapped with a scale of approximately 1:5000. Photos were
encased in mylar and the major cover types at each site were hand
delineated on the mylar and labeled. Delineation varied depending
upon the plant communities present and which could be consistently
resolved based on photographs and ground truth mapping done during
reconnaissance. Table 4 lists the cover types delineated at each
site. Dikes were considered upland and were not delineated on
photos.
When vegetation was sparse but all of the same type, small
interstitial gaps in cover were ignored and the area was delineated
with only one polygon. If two vegetation types were distributed
Table 4. Cover types delineated on air photos.
Orlando Lakeland
Typha spp. Typha spp.
.Scirpus spp. Upland/Grasses
Other emergent Dying willows ,
Scrub/shrub Scrub/shrub
Forested Forested
Floating-leaved Floating-leaved
Dead trees Dead shrubs
Submerged Live/dead shrubs mixed
Open water. Open water
Bare ground
evenly over the same area, the polygon was labelled as both types
and the area was counted twice. This often occurred when floating-
leaved plants formed a solid cover over the water surface within a
sparse stand of Typha or Scirpus. Therefore, the sum of the areas
of different vegetation types at a site can exceed the total
vegetated area. Polygons were electronically digitized. Data were
entered into the ARC/INFO Geographic Information System (GIS) and
estimates were calculated for the indicators listed in Table 3 (B) .
Calculations are described in the Data Analysis section below.
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Acquisition and Use of Existing Data on Water Quality
Under state and federal regulations, constructed wetland
operators are required to sample certain water quality parameters
routinely to demonstrate compliance with standards set for
discharge to streams. Managers at some sites acquire data beyond
what is required and most acquire data on influent to, as well as
effluent from, the wetland for their own performance records.
Table 5 shows the parameters for which data were available at each
site.
At the Orlando site, water samples are collected on three
successive days per month at ten collection stations on the site.
Data for 1989 and 1990 from the influent station in cell 1 and the
effluent station in cell 17 were summarized for this study. When
data were recorded as less than the detection limit, the number
half way between zero and the detection limit was used. For fecal
coliform bacteria counts, however, data were entered as whole
numbers, so an entry of <1 was considered to be zero. For two
samples, fecal coliform counts were entered as <10, and both
Table 5. The types of water quality data obtained from each site.
Ph=Ph (standard units) ; DO==dissolved oxygen (mg/L) ;
BOD=biochemical oxygen demand (mg/L) ; TSS=total suspended
solids (mg/L); NH3-N=ammonia nitrogen (mg/L); TKN=total
Kjeldahl nitrogen (mg/L); TP=total phosphorus (mg/L);
TFC=total fecal coliforms (# colonies per 100 Ml).
Site Parameter
pH DO BOD TSS NH3-N TKN ' TP TFC
Orlando x x x x x x x
Lakeland xxxxx x x x
entries were deleted from the data set before conducting analyses.
When a parameter was not measured (e.g., due to instrument
malfunction), data were entered as missing.
At the Lakeland site, water samples are collected three to
five times per month at eight stations within the WTS, and monthly
averages are calculated for each station and water parameter.
Monthly averages from the influent and effluent stations from
January 1990 through July 1991 were summarized for this study.
Fecal coliform bacteria data were available 'only for 1991.
Samples from the Orlando site are analyzed by the City of
Orlando Bureau of Wastewater Laboratory, Orlando, FL; those from
18
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the Lakeland site are analyzed by the City of Lakeland Wastewater
Treatment Laboratory, Lakeland, FL (Appendix B).
Data Analysis
Vegetation, invertebrate, and site morphology data were
summarized by calculating descriptive statistics for each WTS and
for the cells within the WTS where data were collected. Analysis
of data by cell was intended to show potential patterns in
indicator values along a wastewater treatment gradient.
•Vegetation and water quality data were summarized using SAS,
and invertebrate data were summarized using the Paradox database
system. Air photo data were analyzed with the ARC/INFO geographic
information system.
Water quality data from each site were summarized by
calculating the mean, range, and standard deviation for each
parameter (e.g., pH, total P, etc.) from the inflow and outflow
points of the wetlands. Water quality indicators were summarized
for all sampling dates included in the time frames specified in the
subsection, Acquisition and Use of Existing Data on Water Quality
above.
Vegetation data were analyzed for each site and for each cell
where vegetation was sampled at a site. Species richness was
defined as the total number of species sampled at a site. Average
percent cover of a given plant species was calculated by summing
cover estimates at all sample points and dividing by the total
number of sample points. Structural diversity of vegetation was
evaluated by counting the number of structural layers present at a
site. Structural dominance was assessed by 1) calculating the
average percent coverage of each structural layer per site and 2)
calculating the percentage of species sampled belonging to each
layer. Dominant species were determined by ranking all species at-
a site in descending order based on their average percent coverage
and then summing the average percent coverage values for each
species in order of the ranking until 50% was exceeded. All
species contributing to the 50% threshold and any additional
species with an average coverage of 20% or more were considered
dominants.
Analyses on invertebrates were made by first totaling the
number of individuals of each species from each sampling point.
Percent relative abundance of invertebrate species at each site was
calculated by totaling the number of individuals of each species
and dividing by the total number of individuals of all species
combined. The percent relative abundance of individuals belonging
to each functional group was calculated similarly. The number of
invertebrates collected per person hour was calculated for each
cell and habitat type in which invertebrates were sampled. Species
19
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richness was defined as the total number of species collected at
each site.
Bi-rd densities were calculated by dividing the total numbers
of wading birds seen on any given survey flight by the total area
of each WTS. The area of each WTS was measured by scanning the WTS
boundaries from topographic maps (1:24,000) and measuring the
interior area using SPYGLASS software. Species richness was the
total number of species detected on all surveys. Although cattle
egrets are considered terrestrial, they were seen at all wetlands
and were breeding at the Orlando site and were therefore included
in survey counts.
Indicators were calculated from physical habitat features that
had been digitized and entered into a GIS. Calculations were made
for each entire wetland and for each cell within the wetland as
follows:
• Wetland area was measured as the area within surrounding
dikes. :
• Distance of the land/water interface is the total length
of shoreline in a wetland and is a measure of shoreline
irregularity or development; for this calculation, the
area of floating-leaved plants was considered water.
• Length of shoreline (land/water interface) was divided by
wetland area to normalize the shoreline irregularity
estimate. ;
• Distance of cover/cover interface is the length of edge
between cover types and is a measure of cover type
interspersion.
- • The length of edge between different cover types was
divided by wetland area to normalize the estimate of
cover type interspersion.
•• The area of open water (no vegetation) was divided by
vegetated area (including floating-leaved plants) to
obtain an index of the relative amounts of the two cover
types.
• Relative coverage of selected cover types (Table. 4) was
calculated by dividing the area of each cover type by the
total wetland area.
Survival and reproduction in whole-effluent toxicity tests
were tested against the controls using Dunnett's multiple t-test
for the chronic tests, and a t-test for the acute tests (P<0.05) :
Comparison Data from the Literature
The indicator values obtained from the two WTS were compared
to data from non-WTS obtained from the literature to put the
information from WTS in the context of what was' known about
wetlands in the region. Comparison data were obtained for plant
20
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species richness, percent cover,, invertebrate genera richness,
surface water quality, and bird species richness and density. Data
from WTS and non-WTS were compared- to get a preliminary idea of
where the indicator values for WTS lie in relation to the range of
indicator values from other types of wetlands. Data from
palustrine systems, primarily marshes, in the southeastern United
States were used for comparisons. Comparison wetlands were
natural, created, restored, and enhanced. No further attempt was
made to match comparison sites to the WTS sites studied.
Comparisons were intended to be very broad and preliminary and to
identify any large differences in indicator values between WTS and
non-WTS.
Comparison data were obtained from published documents and
personal communication or records from the southeastern United
States. A library search produced a few journal articles and
agency reports, but many published reports did not contain the
detailed data required for summarizing the indicators of interest,
and it was difficult to find data on many specific indicators'.
Therefore, regional scientists and resource managers were contacted
directly and asked to provide relevant data.
Quality Assurance
Three types of indicator data were used during this study: (1)
data collected in the field (vegetation, invertebrates, bird use,
whole-effluent toxicity); (2) data derived from maps and aerial
photographs (site morphology); and (3) existing data (water
quality) (Table 2) , Laboratory analytical data quality procedures
and data quality objectives (DQOs) for whole effluent toxicity
testing were based on the ERL-Duluth Quality Assurance Plans and
Standard Operating Procedures (US EPA 1988b). Detailed quality
assurance information was not available from bird surveyors.
However, the same two observers were present during all flights,
and they sat in the same positions during all flights. On each
flight, the Orlando site-was surveyed first, the St. Johns marshes
second, and the Lakeland site last. This procedure was implemented
to control the time of day effects within sites.
At all vegetation plots, both members of the field crew
discussed cover percentages for each species in a plot and together
agreed on an estimate. Precision and accuracy were assessed for
identification and percent cover estimation of plants so that, in
case the team members had to identify or estimate percent coverage
separately, the quality control (QC) exercises would indicate the
degree of precision and accuracy in estimates. Because solo work
was unnecessary during the 1991 field season, all estimates were
made by both crew members together. Evaluation of QC data was
therefore not /necessary for interpreting data from this study but
was calculated as a reference for future studies, if needed.
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The following procedures were used to collect and evaluate QC
vegetation data. A QC check was performed at 10% of sampling plots
to determine how similarly the two field crew members were
estimating percent coverage and identifying species. The decision
to make a plot a QC plot was usually made while sampling the plot
just before it. Each person prepared a data sheet and estimated
cover percentages separately without any interaction with the other
crew member. Percent cover precision was computed by calculating
the mean difference between percent cover values recorded by two
team members for each jointly recorded species (i.e., recorded by
both team members in the same plot) . For each team member, percent
cover estimates were summed across all QC plots, by species, for
each species that was jointly recorded. Mean percent cover
estimates for each species and team member were derived by dividing
the percent cover sums by the number of QC plots in which each
species was jointly recorded. The mean difference was simply the
difference in the mean percentages for each team member. Cover
precision for the site was the mean precision for all species.
Plant recognition comparability was calculated by counting the
number of species in each QC plot that were jointly recorded,
dividing by the total number of species observed in each plot,
summing the quotients, dividing the sum by the total number of
plots, and multiplying by 100.
Because vegetation was not sampled at the Lakeland site, QC
calculations were done only for the Orlando site. Plant
recognition comparability was 91%, and the mean percent cover
comparability was 97.3% Both values meet the data quality
objective of 85% set prior to the study. It is recommended that
the QA/QC exercises continue to be part of future field work so
that, in the event that crew members must work alone, a record of
the precision of data collected will be available.
I
Data QC was also performed in the laboratory at University of
Minnesota-Duluth to check the precision and accuracy of the
identification and counts of invertebrates. Contents of 10% of the
sample jars (of sites combined) were re-identified and recounted by
a second person. Subsequently, discrepancies were resolved through
discussion and comparison of results obtained using different keys.
Invertebrate identification comparability "represents the number of
taxa both people jointly observed and identified during the QC
check. It was computed for each QC sample jar by calculating the
ratio of invertebrate taxa jointly observed to the total taxa
observed and multiplying by 100. Identification comparability for
both sites combined was obtained by calculating the mean of all QC
sample jars. The mean identification comparability for
invertebrates was 96%. This value meets the identification
comparability objective of >85% established prior to the study.
The reconnaissance portion of field work included vegetation
mapping, which served as the best guide and accuracy check for
delineation of cover types on aerial photos. One of the field crew
22
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members interpreted and delineated cover types on all photos so
that precision was maximized.
Existing water quality data were evaluated to determine the
usefulness of water quality variables as indicators, not 'to draw
conclusions about constructed wetland performance or to use the
data_ in subsequent analyses. Standard operating procedures and
quality control procedures were obtained from the laboratories that
analyze water samples collected at the constructed wetland sites.
All laboratories follow specified protocols for sample handling and
custody, calibration, analytical procedures, preventative
maintenance, and data reduction and validation. The laboratories
also incorporate QC checks into analyses using duplicates, spiked
samples, split samples, external performance standards, internal
standards, reagent checks, and calibration standards. Protocols
and data quality objectives, however, varied among labs. Because
data from NTS sites were not being compared, data were used
regardless of laboratory protocols and measurement consistency
among testing labs.
23
-------
RESULTS AND DISCUSSION
Summary data are presented separately for each indicator group
for each WTS. Discussion addresses 1) indicator suitability for
future research, 2) wildlife habitat quality, based primarily on
comparisons to non-WTS data from the literature, and 3)
recommendations for fo.llow-up studies. It is recognized that study
methods (e.g., sample design and intensity), wetland size, and
various other factors confound comparisons with literature data.
Comparisons, however, are used simply for establishing a context
for making general postulations about the ecological condition of
the two WTS studied and for generating hypotheses for future
research.
Vegetation
Because much of the Lakeland site was inaccessible for
sampling, vegetation was sampled quantitatively only at the Orlando
site. Plants sampled at the Orlando site belonged to all six
structural layers identified: emergent, submergent, floating-
leaved, scrub/shrub, forested, and dead. The emergent layer was
the most dominant, with an average percent coverage of 81% -and
containing 67% of the species sampled at the site (Table 6). The
float ing-leaved and dead layers were eilso common, with average
percent coverages of 52% and 34%, respectively. Although the,
scrub/shrub layer had one of the lowest percent coverages, it had
the second highest species richness (Table 6) . Conversely, the
high percent cover of floating-leaved species was due to only 11%
of the species sampled. The dead category was composed primarily
of -persistent emergent vegetation (Scirpus and Typha). Dead
vegetation was evaluated separately because it can contribute cover
for waterfowl or nesting habitat for passerines that is different
from cover of live plants of the same species.
Structural types were the most diverse and well-interspersed
in the mixed marsh hardwood swamp habitats at the Orlando site
(cells 13-17, Fig. 1)). These cells are designed and managed to
provide habitat, and the varied vegetation structures result in
habitats for a variety of species and activities (e.g., feeding,
roosting, nesting). The deep marsh areas (cells 1-12) were
designed primarily for water treatment and are comprised
predominantly of bulrush and cattails with interspersions of
float ing-leaved species, shrubs, and a few palm groves. Vegetation
structure in those cells is more uniform, but scattered openings in
an otherwise dense growth of vegetation provide protected areas
and, in a few areas where snags or shrubs are present, serve as
bird rookery sites.
Wildlife use of a habitat for nesting and cover is usually
considered to be more dependent on the structure of vegetation than
on the species of vegetation (Beecher 1942, Weller and Spatcher
24
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1965, Swift et al. 1984). Well-interspersed vegetation structures
are often associated with high diversity and abundance of wetland
dependent birds. Complex plant zonation results in an increase in
the number of niches available for breeding birds (Swanson and
Meyer 1977, Weller 1978, Dwyer et al. 1.979, Ruwaldt et al. 1979,
Roth 1976). The diversity and interspersion of plant community
structures in cells 13-17 at the Orlando site likely satisfy the
needs of many wetland-dependent wildlife species.
The particular species of plants are important when
considering wildlife food preferences. Plant species sampled and
their average percent coverages per square meter are listed for the
Orlando site in Table 7. Standard deviations of average percent
cover are high due to patchiness in spiecies distribution, which
often results in highly variable cover values. The interspersion
and patchiness of plant species, however, can enhance wildlife
habitat.
Dominant species are those whose percent coverages comprise
the first 50% of vegetative cover on a site when ranked in
descending order, plus any species whose coverages are 20% or
greater. Dominant cover types at the Orlando site were dead
emergents and Lemna spp. Species that were common but which were
not classified as dominants were Salvinia rotundifolia (17.9%),
Typha spp. (16.2%), and Hydrocotyle umbellata (13.7%) (Table 7).
The majority of plant species identified had average percent site
coverages of less than 1%. Dominant species varied to some degree
from one cell to another. Dead emergents were dominant in all
cells sampled. Lemna spp. was dominant in three of the four cells
sampled, but comprised an average of only 2% of the cover in the
hardwood swamp community of cell 16. Also dominant in cell 16 was
Hydrocotyle umbellata, Ludwigia peruviana, Panicum spp. and
Salvinia rotundifolia. Aside from deiad emergents a'nd several
float ing-leaved species, Typha spp. was dominant in cell 2, and
Scirpus californicus was dominant in cell 9. Floating-leaved
species are consumed by many species of waterbirds. Typha spp. and
Scirpus spp. are important as cover for many species of birds but
are consumed by few species of wildlife.
Species richness (the number of species sampled) at the
Orlando site was 63. For comparison, the numbers of plant species
at several non-WTS marshes in Georgia and Florida ranged from 9 to
68 (Table 8) . In addition, plant species richness in 25 non-WTS
Lower Mississippi River borrow pits ranged from 65 to 196 for the
period 1981-1983 (Buglewitz et al. 1988). Brown (1991) reported
plant species richness between 13 and 93 for 18 created and natural
non-WTS in Florida in 1988. Erwin (1991) reported plant species
richness values between 7 and 39 for wetland mitigation habitats in
Florida. Plant species richness at the Orlando WTS was within the
range of values reported for non-WTS. Post, Buckley, Schuh, and
Jernigan, Inc., the City of Orlando contractor which conducts
regular sampling on the site, has identified 150 plant and tree
26
-------
Table 7. Frequency of occurrence and average percent cover per square
meter ± standard deviation for each plant species sampled at
the Orlando site, 1991. .-Frequency of occurrence is the
percent of sample points at which each species was present.
Average percent coverage was rounded to 0.0 if it was below
" 0.05%. The sum of percent coverages at a site can exceed 100
since species can have overlapping coverages. The total
number of points sampled was 65.
Frequency of Average percent
Species Occurrence (%) . cover7m2 +/Std. Dev.
i
Emergent
Aeschynomene indica 2 o.2 ± 1.2
'Alternanthera philoxeroides 3 0.7 T 4.5
Al ternanthera sessilis 2 0.0 ±0.1
Andropogon virginicus 2 0.2 T 1.2
Bacopa monnieri 5 0.2 ±1.4
Bidens spp. • 2 0.2 T 1.2
Carex albolutescens 2 0.0 ± 0.1
Carex spp. 2 0.1 T 0.6
Centella asiatica 12 0.7 ± 2.3
Conoclinium coelestinum 2 0.1 T 0.6 '
-Commelina diffusa 6 1.6 Til.2
Cyperus haspan 2 0.0 T 0.1
Cyperus odoratus 6 0.3 ± 1.5
Dichromena colorata 3 0.2 ± 0.9
Diodea virginiana 5 0.2 ± 1.2
Echinochloa spp. 2 0.0 ± 0.1
Eleocharis spp. 2 - Q.3 T 2.5
Galium spp. 9 0.2 T 0.9
Galium tinctorium 2 0.1.+ 0.6
Juncus effusus 5 0.5 ± 2.1
Ludwigia peruviana 6 5.6 ±22.4
Ludwigia repens 2 0.1 ± 0.6
Lycopus rubellus 3 0.2 ± 1.2
Mixed grasses 2 0.5 ± 4.3
Mikania scandens 9 ' 2.8 ± 13.7
Myrica cerifera 2 0.8 T 6.2
Panicum repens 25 8.5 ± 22.9
Panicum spp. 5 4.4 ± 20.4
Paspalum urvillei 5 0.4 ± 1.8
Phyla spp. 12 2.5 ± 11!7
Pontederia cordata 5 .2.7 ± 14.7
Polygonum punctatum 12 1.6 ± 5.7
Rhynchospora spp. 2 0 . 5 ± 4 .3
Sagittaria lancifolia 8 1.3 ± 8.2
Scirpus americanus 5 1.2 ± 8.1
Scirpus californicus 6 . 5.5 T 21.9
Setaria geniculata 2 0.2 ± 1.2
27
-------
Table 7, continued
Species
Smilax bona-nox
Typha spp.
Unidentified emergent 1
Unidentified emergent 2
Unidentified emergent 3
Submerged
Cera tqphyll urn demersum
Chara spp .
Najas guadalupensis
Utricularia foliosa
Utricularia spp.
Float ing- leaved
Azolla caroliniana
Eichhornia crassipes
Hydrocotyle ranunculoides
Hydrocotyle umbellata
Lemna spp.
Limnobivm spongia
Salvinia rotundifolia
Wolffia spp.
Scrub/shrub
Frequency of
Occurrence (%)
2
34
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2
2
26
6
11
9
6
20
11
28
54
17
51
3
Boehmeria cylindrica 3
Bupatorium capilli folium 6
Bupatorium filamentosa 2
Sabal minor 5
Unidentified shrub 2
Urena lobata 2
Liguidambar styraciflua (seedling) 3
Forested
Nyssa sylvatica 3
Sabal palmetto 15
Dead
Emergent 55
Scrub/shrub 2
Forested 18
Average percent
cover /m2 +/Std. Dev.
0.1 ± 0.6
16.2 + 29.5
0 . 1 +_ 0 . 6
0 . 0 ± 0 . 1
0.2 ± 1.2
4 . 6 ± 14 . 5
0.1+0.2
2.3 +. 10.4
3.9+15.4
1.0 +. 6.3
5.8 ± 18.7
1.7
12.4
"3.9 ± 15.6
13.7+27.5
26.7 +35.7
5.4 +_ 18.3
17.9 ± 30.7
1.3 ± 7.5
0.2 +.
0.8 ±
0.2 +.
0 . 5 ±
0.1+
0 . 3 ±
1.4
4.5
1.2
2 . 6
0.6
2 . 5
0.2 ± 1.4
0.5+2.8
6.4 + 18.1
30.4 ± 36.9
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1.7 + 4.7
28
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species at the Orlando site since its construction (personal
communication, Post, Buckley, Schuh, a.nd Jernigan, Inc., Winter
Park, FL) , which places the site above most non-WTS with respect to
plant species richness. . •
Vegetation is one of the most significant components of
wildlife habitat, and the continued development of indicators of
vegetation for the assessment of habitat quality in WTS is
recommended. The methods used in this, study, were effective for
characterizing vegetative structure, and percent cover of plant
species. Identification of unknown species by regional botanists
assured accuracy and eliminated the need for later laboratory
processing of samples. Sampling was possible during a single site
visit at the peak of plant growth. Other researchers have also
found vegetation indicators to be effective for wetland monitoring
(e.g., Aust et al. 1988; Brooks et al. 1989; Brooks and Hughes
1988; Brown et al. 1989; US EPA 1983; Sherman, personal
communication, J.D. White Company, Vancouver, WA).
Because the Orlando site was large, additional sampling time
might have better characterized the diversity of plant communities.
Adequate sampling time should be allowed, depending on site size
and community diversity. Alternatives to transect sampling may be
necessary for inaccessible sites, such as the Lakeland site. Some
vegetation indicators can be obtained from aerial photographs, and
field verification can then be accomplished with minimal time and
effort during field visits.
Because structural diversity is an important component of
wildlife habitat quality, future work could include development of
methods for quantifying structure, particularly within the emergent
category, which is usually dominant in WTS. Short and Williamson
(1986) describe one method for measuring the relative'structural
diversity of terrestrial habitats using the Habitat Layer Index,
originally developed for use with the Hcibitat Evaluation Procedure
(HEP) (U.S. Fish and Wildlife Service 1980) . It may be possible to
test and develop methods such as this for wetland habitats.
Evaluation of habitat quality should focus less on plant species
richness and cover types. Species-specific information, hbwever,
can be used to extract various metrics such as the abundance of
wildlife food plants or rare and sensitive plants.
Invertebrates
Eight and one-half person-hours were spent sampling
invertebrates at the Orlando site, and six person-hours were spent
at the Lakeland site. The total number of invertebrates collected
was 785 (92.4 per person-hour) at .the Orlando site and 1639 (273.2 .
per person-hour) at the Lakeland site. Forty-nine taxa were
collected at the Orlando site, and 52 taxa were collected at the
Lakeland site.
30
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:es at the Orlando and Lakeland
collected was 785 and 1639 at
ional groups were not assigned
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Non-insect invertebrates were dominant at both Florida sites,
particularly at the Lakeland.site (Table 9). Dominant non-insect
invertebrates were primarily from the class Crustacea, order
Decapoda, at the Orlando site and orders Decapoda and Amphipoda at
the Lakeland site. Palaemonetes in the family Palaemonidae were
the dominant decapods at both sites, comprising 18.5% of the
Orlando site total and 18.2% of the Lakeland site total. At the
Lakeland site, Amphipoda were also numerous and were composed
entirely of Hyalella azteca of the family Talitridae (30.2% of the
site total).
Coleoptera was the most numerous insect' order. It was found
in abundance only at the Orlando site and consisted primarily of
Peltodytes in the family Haliplidae (13.2% of the site total) . The
majority of taxa collected at both sites had relative abundances
less than 1%.
Aquatic insect orders not represented in Table 9 are
Collembola, Plecoptera, Neuroptera, Megaloptera, Hymenoptera, and
Trichoptera. Aquatic Collembolans have a spotty distribution and
are most common in the early spring or late autumn (Pennak 1978).
Plecoptera are usually associated with clean, cool running waters
or large oligotrophic lakes .(Merritt and Cummins 1984) . Aquatic
Neuroptera comprise only one family, the larvae of which are
associated with fresh water sponges. Large numbers of these and
the Megaloptera are rarely seen because they are short-lived and
many species are nocturnal (Merritt and Cummins 1984). These
characteristics may partially explain the absence of some aquatic
insect orders in the WTS samples. Ephemeroptera numbers were low
at both sites. Most Ephemeroptera prefer a high concentration of
dissolved oxygen (Pennak 1978).
Many species of Chironomids tolerate the, low oxygen' conditions
in wetlands (Adatnus and Brandt 1990) and are often an important
component of a wetland's macroinvertebrate community. Chironomid
abundance and species richness was relatively low at both sites
(Table 9) , but benthic sampling was not conducted. Benthic
sampling is recommended for future studies to assure accurate
estimation of all invertebrate groups. Ratios of the number of
invertebrate species tolerant of low oxygen ,to those that are
intolerant have often been used to indicate ecological status of
surface waters, and could be tested for use in wetlands (Adamus and
Brandt 1990).
The number of invertebrates collected per hour is related to
density. The highest collection rates occurred at the Lakeland
site, particularly in cells 1 and 5 (Table 10). Macroinvertebrate
abundance normally increases with increasing nutrient
concentrations (Cyr and Downing 1988, Tucker 1958). High abundance
in cell 1 is likely due to higher nutrient concentrations and high
productivity nearer to the inlet of the wetland (see Table 17 in
Water Quality section below). The high abundance in cell 5 could
be caused by water enrichment by the colonial waterbirds that breed
on the islands in that cell.
35
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The high collection rate in cell 6 at the Orlando site may be
more related to the habitat than the position of the cell. The
sample was the only one at that site that was taken in a Scirpus
spp. habitat, where the collection rate of 141/hr is noticeably
higher than in other habitats at the site (Table 11). Invertebrate
collection rates were also highest in the Scirpus spp. community at
the Ocean Springs WTS studied in Mississippi (McAllister 1992). -
Because the same habitats were not sampled in every cell, the
effects of cell number and habitat type are confounded in these
analyses. Although it is often difficult to find the same habitat
types in every cell, a more sound experimental design and analysis
of variance of the influences on invertebrate abundance should be
attempted in future studies. Identifying the factor that explains
most of the variance in invertebrate abundance or the plant
community that is most suitable for both habitat and water
treatment might provide information for designing WTS to enhance
habitat quality.
Table 12 shows the percent relative abundance of invertebrate
functional groups present at the Orlando and Lakeland sites. A
total^ of 363 invertebrates (46.2%) at the Orlando site and 965
(58.9%) at the Lakeland site were not assigned functional groups.
These invertebrates included immatures, terrestrial invertebrates,
and non-insect invertebrates. The high percentage of unassigned
functional groups was due to the high abundance of crustaceans at
both sites (Table 9) . Predators were the most dominant functional
insect group at both sites (35.0% relative abundance at the Orlando
site and 32.5% at the Lakeland site). At the Orlando site, the
piercer/shredder group comprised 13.2% of the total, the result of
a high abundance of Peltodytes. All other functional groups
comprised less than 4% of the total at each site.
The distribution of invertebrates among functional feeding
groups is difficult to evaluate because the functional evaluation
of Vannote et al. (1980) is based on lotic systems. Wetlands are
usually predator-based systems (Hoke Howard, personal
communication, U.S. EPA Region 4, Athens, GA) . Although no current
protocol exists for evaluating the viability of a macroinvertebrate
community of a wetland, comparisons of functional group composition
between reference wetlands and the wetland in question are
sometimes made to identify differences in community structure. In
contrasting a reference wetland to another wetland, biologists in
Region IV have observed the elimination in impacted wetlands of
certain taxonomic groups such as amphipods and odonates (H. Howard,
personal communication, U.S. EPA Region IV, Athens, GA) . This kind
of comparison might be considered for functional groups in future
studies if reference sites are sampled simultaneously.
For comparison, genera richness of invertebrates varied from
25 to 41 in four non-WTS palustrine wetlands in North Carolina
(MacPherson 1988). In addition, genera richness for, invertebrates
37
-------
Table 12. Relative abundances of invertebrate functional groups,
Orlando and Lakeland sites, Florida, 1991. Terrestrial
and non-insect invertebrates were not assigned functional
groups.
Orlando Site
Functional Group Relative Abundance
Not assigned 46.2%
Predator . , 35.0
Predator/collector 0.9
Collector/scraper 0.5,
Collector . 1.4
Piercer/collector 0.9 .
Piercer 0.1
Piercer/shredder 13.2 ;
Collector/shredder 0.8
Shredder 0.1
Shredder/collector/predator 0.5
Shredder/collector/scraper/piercer 0.3
*
Lakeland Site
Functional Group Relative Abundance
Not assigned : 58.9%
Predator - 32*5
Collector 0.7"
Collector/scraper : 0.9
Collector/shredder 1.5
Shredder 0.2
Shredder/collector/predator 0.1
Shredder/collector/scraper/piercer 3.9
Piercer 0.7.
Piercer/shredder 0.1 '
Piercer/collector 0.4
38
-------
in several Lower Mississippi River abandoned channel and oxbow
palustrine wetlands in 1984 ranged from 8 to 28 (Lowery et al.
1987) . Erwin (1991) reported invertebrate species richness between
7 and 44 for various sections and habitats in wetland mitigation
sites in Florida. - Genera richness for benthic invertebrates in
several Lower Mississippi River borrow pit palustrine wetlands
ranged from 7 to 29 in 1981 (Cobb et al. 1984).
The taxon level to which invertebrates are identified, the
collection techniques, and the group of invertebrates collected
(e.g., nektonic, benthic) vary, so comparison is difficult.
Nevertheless, genera richness values of 49 and 52 for the Orlando
and Lakeland sites, respectively, appear to be high compared to the
range of richness values from non-WTS in the same region. Data on
invertebrate abundance as determined with the Timed Qualitative
Sampling Technique were not found for comparisons, so invertebrate
abundance in the two WTS studied in relation to that in non-WTS
could not be assessed..
Continued development of macroinvertebrates for habitat
evaluation in WTS is recommended. In this study, the semi-
quantitative sampling method was simple to implement, required
minimal equipment, and could be adapted for difficult sampling
situations, such as at the Lakeland site. It can easily be done in
a variety of selected habitats during a single site visit.
Macroinvertebrates have been suggested as monitoring
indicators by various other researchers (Brooks et al. 1989, Brooks
and Hughes 1988, Brown et al. 1989, Schwartz 1987, US EPA 1983).
Macroinvertebrates are important to habitat quality and system
function because they serve as a major food source for waterbirds,
fish, reptiles, and amphibians, and they are a critical link
between primary production/detrital resources of systems and higher
order consumers (Murkin and Batt 1987, Murkin and Wrubleski 1987).
Because of their relatively low position on the food chain,
invertebrates can serve as indicators of food chain function and
its implications for higher organisms. Invertebrates are also .less
likely than birds or mammals to migrate from one wetland to
another.
Further development of macroinvertebrate indicators should
include standardization of collection methods, expansion of
collection techniques (e.g., sampling for benthic invertebrates),
looking for relationships between invertebrate abundance and bird
use, adherence to a rigorous experimental design, and simultaneous
sampling at reference sites.
The time and cost involved in identification might be a
limiting factor in future monitoring work, and approaches should be
explored for simplifying the identification process, such as
sorting by gross morphological characteristics, order, or family.
A courser level of sorting can often be done in the field after
39
-------
collection, does not require collection and laboratory
identification (Robert Knight, personal communication, CH2M Hill,
Gainesville, FL) , and might provide sufficient information for
assessing habitat quality. The abundcince of specific taxonomic
groups, such as Chironomids or Oligochaetes, could also be tested
as indicators of environmental conditions at a site. Functional
group data might be- useful for comparisons with reference wetlands
and for future development of protocols for assessment of
invertebrate community viability in wetlands, but their usefulness
as an effective indicator at this time is uncertain.
Whole Effluent Toxicity Tests
There were no statistically significant toxicity effects
(P<0.05) at either site for the Ceriodaphnia acute or chronic tests
or for the fathead minnow acute tests on the Orlando water sample
(a fathead minnow test was not done for the Lakeland sample) .
Survival was 80% or more for all samples (Table 13) . Measurements
of each water sample performed by the Duluth Laboratory are shown
in Table 14, and initial and final chemistries for water samples
and the controls are shown in Appendix p.
Toxic heavy metals, primarily from industrial sources, and
organic contaminants are sometimes present in municipal wastewater
(US EPA 1984, Hicks and Stober 1989, Richardson and Nichols 1985).
Their-concentrations are typically reduced by approximately 30-95%
in secondary treatment before entering a wetland (Richardson and
Nichols 1985) . In addition, most WTS do not receive water from
industries. The wastewater treatment plant in Lakeland does
receive wastes from industries in the a.rea, and some heavy metals
have' been detected in the WTS. Some wetland influent silver,
cadmium, and zinc concentrations exceed the Florida standards for.
class III waters, although the wetland brings the effluent averages
into compliance with the standards (Post, Buckley, Schuh, and
Jernigan, Inc. 1992) . Although there is no indication that any of
the average metal concentrations are increasing through time, the
concentrations are of concern to the city of Lakeland.
The field sampling, sample transfers, and laboratory
procedures involved in whole-effluent toxicity testing were
successful in the pilot study. The method is feasible
logistically, and the data are of high quality for identifying
potential problems requiring further testing. Single, whole-
effluent toxicity tests, however, will not be effective unless a
contaminant is entering the wetland at the time of sample
collection. To increase the probability of detecting potential
contaminants, whole-effluent tests should be conducted on a routine
basis and should be one of several initial assessments focussed on
wetlands suspected as higher riskis for the presence of
contaminants, such as the Lakeland site. Another initial test
could be the measurement of sediment concentrations of
40 . !
-------
Table 13. Reproduction and survival of Ceriodaphnia dubia.
Sample
Orlando
Influent
Effluent
Control
Lakeland
Influent
Effluent
Control
Mean young/original female
(95% confidence interval)
26.4 (20.2-32.8)
25.6. (21.4-29.8)
25.2 (18.5-31.9)
19.9 (11.8-28.0)
25.7 (19.1-32.3)
20.9 (12.2-29.6)
Mean Survival
100
100
100
80
90
lO'O
Table 14. Measurements on water samples performed by ERL-Duluth
immediately upon arrival of samples at the laboratory.
Sample
Orlando
Influent
Effluent
Lakeland
Influent
Effluent
Hardness
(mg/L as
CaCQ,)
119
93
180
360
Alkalinity
(mg/L as
CaCO,)
85
80
130
85
Ammonia
N:NH3
(mg/L)
TRC*
(ma/L)
0.03
0.02
0.04
0.70
TRC=total residue chlorine
41
-------
contaminants.
Suspect wetlands might be those where toxic substances or
metals have been found in the past, where wastewater treatment
plant user violations have occurred in the past, or where routine
sampling suggests possible problems. Signs of possible problems
might be a sharp reduction in invertebrates present, signs of
stress or disease in birds that use the WTS, or a combination of
indicator measurements that suggests a marked decrease in wetland
integrity from one year to the next.
If contamination is detected in initial tests, a full
examination should follow to measure tissue concentrations of
contaminants in aquatic organisms, to determine whether
bioaccumulation is occurring, and to relate tissue levels of
contaminants to adverse effects on wildlife. A full examination,
however, is a much more lengthy and expensive process than a
general assessment of wildlife habitat quality and thus should be
a separate activity. Results of these preliminary whole-effluent
tests should not be used to evaluate wildlife habitat quality until
a full examination of the contamination can be conducted and
wildlife risks can be assessed.
Bird Use
This section provides summaries of: 1) wading birds surveyed
on six surveys at the two WTS and at natural marshes near the St.
Johns River; 2) breeding wading bird foraging use of WTS and
surrounding wetlands based on following flight data; and 3) results
of ground surveys conducted at the Lakeland site. Aerial bird
surveys were designed to explore the range and. variability of
wading bird use of WTS and to compare bird use of nearby natural
wetlands with WTS. Cursory ground surveys were conducted to
provide ancillary data about use by species that were not surveyed
from the air. Species 'composition and abundance were highly
variable on a monthly basis. Between-site consistency was low,
while differences within sites was high from month to month. Also,
variation in numbers of each species at each site in the winter and
spring periods was very high. Results therefore cannot be used to
determine whether WTS are more or less attractive than natural
wetlands. However, several observations are notable.
Aerial Surveys
A total of ten species of waterbirds were detected on aerial
surveys at the Orlando site, and nine species were detected at the
Lakeland site. Species richness varied from a low of three at the
Lakeland site in December to a high of eight at both sites during
the March, April, and May surveys (Table 15) . Species richness was
higher at the Orlando site than at the Lakeland site on four of the
42
-------
six surveys. Species richness, however, is difficult to estimate
by aerial surveys, so the1 accuracy of the above figures is
uncertain.
The highest counts of foraging and breeding wading birds at
the two WTS sites occurred at the Lakeland site where breeding wood
storks and great egrets were abundant during the March and April
surveys in the cell 5 rookeries. Great egrets were also abundant
in October at the Orlando site and in February and May at the
Lakeland site. Wading bird densities at the WTS sites varied from
a low of 0.04 birds/ha at the Lakeland site in October 1991 to a
high of 0.71 birds/ha at the Lakeland site 'in April 1992 (Table
15) .
In comparison, ten wading bird species were surveyed at the
natural St. Johns marshes over the survey period. Species richness
varied from four to nine for each survey. Foraging and breeding
wading bird densities were higher at the St. Johns Marshes than at
the two WTS for the December, February, and March surveys (Table
15). The high densities were largely due to flocks of white ibis.
When white ibis are removed from the analysis, differences in
overall and species-specific densities among the three sites are
much less discernable (Frederick and McGehee, personal
communication, University of Florida, Gainesville, FL) . Densities
varied from 0.02 birds/ha in October to 1.64 birds/ha in February.
Among all three sites surveyed, densities of foraging and breeding
birds combined were highest in April and May at the Lakeland site,
due to large numbers of nesting wood storks and great egrets, and
in October at the Orlando site due to large numbers of non-nesting
great and snowy egrets.
In addition to surveyed species, the Irpn Bridge site
attracted large numbers of blue-winged teal, including'520 on the
December survey. On' the March survey, 45 mottled ducks were seen
at the Orlando site, while 111 were seen at the St. Johns Marshes.
Ducks were not found in large numbers at the Lakeland site.
Cormorants and anhingas were consistently seen at both WTS during
surveys, and roosting black and turkey vultures were noted at the
Orlando WTS. :
Wading birds formed colonies at both of the WTS but not in the
St. Johns Marshes. Breeding at both sites was apparently
successful, although nest checks and counts of immature birds were
not conducted. The Lakeland site had the largest colonies,
composed primarily of wood storks and great egrets. The highest
colony counts at the site included 190 wood storks and 180 great
egrets in March, and 272 wood storks and 173 great egrets in April.
At the peak of nesting activity, surveyors counted between 145 and
188 wood stork nests, 155-173 great egret nests, 12 snowy egret
nests, 8 white ibis nests, and 235 double-crested cormorant nests
on the islands in cell 5 (the ranges of estimates result from
differences between aerial and ground estimates). The wood stork
43
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and great egret nesting attempts at Lakeland were apparently
successful. Although nest success was not monitored, many chicks
of both species were seen fledging from the islands in late May and
early June. The success of snowy egret nests is less certain.
During a separate May 7 observation at the Orlando site, 13
nesting great egrets were counted in a palm grove in the southwest
corner of the site, and 5 nests were counted in palms in the
northeast corner. The birds probably began nesting in the last two
weeks of April. On the May 18 survey flight, 55 pairs of nesting
cattle egrets were counted in the center of the WTS. Because the
May survey was the last one conducted, it is riot known whether this
colony grew, but a late May initiation and early summer building of
the colony would be characteristic for cattle egrets (Frederick and
McGehee, personal communication, University of Florida,
Gainesville, FL).
The persistence of breeding colonies at both WTS suggests that
the sites are valuable as nesting habitat. Birds are attracted by
the deep, permanent water at the WTS sites. At natural wetlands in
central Florida, water depth is less predictable from year to year.
With a dependable water supply, WTS may have great importance as
breeding sites in an area where many breeding wetlands are being
lost or annual conditions are variable.
When breeding birds are removed from the survey counts, the
value of the St. Johns Marshes as foraging habitat is apparent.
Foraging bird densities were higher at those marshes on four of the
six surveys (Table 15; Figure 2). The high densities in the
December, February, and March surveys are due primarily to large
flocks of foraging white ibises. White and glossy ibis appeared to
prefer the St. Johns marshes over the WTS site,s for foraging
(Figure 3) . Very few white ibises were surveyed at the Lakeland
site. Large flocks of shorebirds were also noted at the St. Johns
sites but not at either of - the WTS sites. Of the three sites
surveyed, it appears that the shallower St. Johns Marshes are most
effective in attracting shallow-water and moist soil foragers such
as ibis and shorebirds (Frederick and McGehee, personal
communication, University of Florida, Gainesville, FL). The St.
Johns Marshes also appeared to be more important than the two WTS
for foraging great and snowy egrets and wood storks (Table 15).
Although the St. Johns Marshes are used to a greater degree by
foraging birds than the two WTS, the foraging wading bird densities
at all three sites surveyed appear to be high in comparison with
other tropical and subtropical wetlands that have been surveyed
using similar methods (Figure 4). Two of these comparison wetland
types, mangrove areas of the Everglades and the freshwater
Everglades, are known to attract high concentrations.and a large
proportion of the southeastern wading bird populations (Bancroft
1989, Bancroft et al. 1992). When numbers of breeding birds are
included in density calculations, the densities at the Lakeland
45
-------
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site are much higher for the last three surveys and are more
similar to the St. Johns Marshes, with the exception of the
February survey. These observations suggest that the habitat value
for foraging and breeding wading birds at the two WTS sites is
high. The value of a wetland to wildlife is also greatly
influenced by its position in the landscape and the habitat
requirements that are available on a larger scale. The value of
the Orlando site is enhanced by its position near the productive
St. Johns Marshes because nesting birds are in close proximity to
several important feeding areas.
Following Flights
Surveyors followed a total of 166 birds from colonies at the
two WTS, Lake Mary Jane (27 km southwest, of the Orlando site) , and
Homeland (14 km southeast of the Lakeland site) . Most of the
flights followed great egrets, snowy egrets, and white ibises.
Birds from the two natural wetlands did not travel to the WTS
sites to forage. However, this was probably because sufficient
foraging wetlands existed close to the natural wetlands or because
the species of birds followed typically do not travel more than 20
km to feed (Frederick and Collopy 1988, Bancroft et al. 1991). All
of the flights from Lake Mary Jane and Homeland were less than the
distance from those sites to the WTS sites. Therefore, the results
of following flights are inconclusive with respect to bird
preference of WTS versus non-WTS.
The WTS sites were valuable as foraging areas to resident
nesting great and snowy egrets. Foraging flight destinations were
within the WTS sites for 65% of the flights at the Lakeland site
and 46% of the flights at the Orlando site. Of the flights that
ended elsewhere, the majority from the Lakeland site ended at
phosphate pits and artificial ponds and ditches, while most from
the Orlando site ended at natural wetlands. This is consistent
with the types of wetlands available in the vicinity of each of the
WTS sites.
Ground Counts and Ancillary Bird Data
Ground surveys, conducted independently of aerial surveys at
the Lakeland site, provided cursory data on non-wading bird species
richness and relative abundance. During the five ground surveys at
the Lakeland site, 57 species were detected (Appendix E) . Six
additional species were detected during the field visit in August.
Total birds counted in the 10 designated areas at the site ranged
from a low of 574 in December, 1991, to a high of 1011 in June,
1992. The most abundant species on the first three ground counts
(November, December, and January) were double-crested cormorants,
which were seen mostly on the breeding islands in cell 5. On the
48
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Density (birds/km2)
150
100
50
jfr
|i
l
Coastal
._ . .
Central Everglades
Everglades
Nicaragua
ILlI
II!
Southwest
T?
1
I I I I 1 I
Orlando St. Johns Lakeland Other Subtropical Wetlands
Figure 4. Comparison of non-breeding wading bird densities at the
WTS and St. Johns sites with the results of similar
surveys at subtropical non-WTS wetlands (adapted from
Frederick and McGehee , personal communication, University
of Florida, Gainesville, FL) . Bars for the Orlando, St.
Johns, and Lakeland sites represent months of the 1991
surveys, as shown for Orlando. Bars for the remaining
sites represent results from multiple surveys. Data are
from Hoffman et al. (1990) for the central Everglades,
Jelks (1991) for southwest Florida, Robin Bjork and
George Powell (unpublished, personal communication, P.
Frederick, University of Florida, Gainesville, FL) for
the coastal Everglades, and Peter Frederick and Marilyn
Spalding (unpublished, personal communication) for the
Miskito Coast of Nicaragua.
49
-------
March and June surveys, the colonial nesting species -- wood stork,
great egret, anhinga, snowy egret, and double-crested cormorant --
were most numerous. ,
Because ground and aerial counts were usually not
simultaneous and because ground counts did not provide complete
areal coverage of the site, it is difficult to .use one type of
survey to evaluate the accuracy of the other. However, it would be
preferable to do this kind of evaluation in future studies to
estimate the error associated with aerial surveys. The only ground
count that was conducted on the same day as an aerial survey was
the December 17 count. More species of wading birds were detected
on that count than on the aerial survey, but fewer individuals of
each species were counted. This suggests that species
identification may be a problem on aerial surveys, while bird
counts may be difficult from the ground when not all areas of the
site are visible. If all areas of the site are not accessible on
the ground, which is the case at the Lakeland site, one approach
would be to obtain separate aerial counts in a smaller area that is
also visible from the ground so that comparisons and error
estimates can be made using both types of counts.
A total of 141 bird species have been recorded (as of 1991)
for the Orlando site by Post, Buckley, Schuh, and Jernigan, Inc.,
the city of Orlando site contractor (Appendix E) . The Orlando list
represents a greater amount of time and effort devoted to inventory
of the biota present at the site and is likely to be more complete
than the Lakeland site list. Species seen during routine field
work in August, 1991, are indicated on the lists.
At several southeastern palustrine non-WTS comparison
wetlands, species richness ranged from 13 to 98 (Edelson and
Collopy 1990, Henigar and Ray 1990, U.S. Army Engineer Mississippi
River Commission, 1986). Richness at the Orlando site is above
this range of values, while richness at(the Lakeland site falls in
the upper half of the range.
Bird Indicator Discussion
The intensity of bird use at the two WTS can probably be
attributed to the large size of the sites, the availability and
diversity of suitable habitats within the sites, and the observed
high biological productivity. Both WTS have been stocked with
fish, which is likely an important food resource for colonial
nesting birds at the WTS, as evidenced by destinations within the
WTS of many of the bird following flights. Sixteen species of fish
have been observed at the Orlando site (personal communication,
Post, Buckley, Schuh, and Jernigan, Inc., Winter Park, FL) ,
including Florida gar, largemouth bass, bluegill, and bullhead.
Apple snails (Pomacea spp.) , food of the snail kite, we're also very
abundant. Bird species richness is high, which suggests a gopd
50
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habitat diversity and suitability. Benefits to wildlife from use
of wastewater for habitat r?enhance.ment have been reported in
numerous other cases (e.g., Cedarquist and Roche 1979, Cedarquist
1980a, 1980b, Demgen 1979, Demgen and Nute 1979, Wilhelm et al
1988).
It is possible that bird use indicators may be useful for
future habitat assessments, but the time and level of effort
required for bird surveys should be considered. Birds are very
mobile, and their use of a wetland may be erratic and/or seasonal.
To adequately characterize bird use, multiple surveys, throughout
at least the spring and fall migratory seasons, are necessary.
Advanced planning must assure that necessary work contracts,
personnel, and funding are arranged on time so that surveys
coincide with the annual cycles of bird use.
Birds are more visible and audible than other faunal
components and are easily identified by trained biologists, which
makes bird use a relatively reliable measurement in many cases.
Information on birds is sometimes useful for assessing other system
components, such as the types of food resources that might be
present in the wetland or the presence of habitat features required
by certain species. Because birds are mobile and- often use a
complex of wetlands, most species might be better as indicators of
overall landscape conditions than of single wetland conditions'
(Adamus and Brandt 1990).
If traditional bird surveys are continued in future studies
and monitoring efforts, the following should also be considered:
• At least some effort should be devoted to ground counts
to: verify aerial survey data; estimate the error
associated with aerial counts; and survey other groups of
birds that are not detectable from the air, such as
passerines and shorebirds. Ground counts should be done
immediately prior to aerial counts and should maximize
areal coverage of a site. This level of effort, however,
may be too great for sites as large as the two WTS
visited in Florida.
• The amount of sampling effort that can be devoted versus
that required to obtain an accurate representation of
bird use, density, and diversity should be evaluated. If
the level of effort possible is insufficient to make
accurate estimates, then objectives should be . re-
evaluated, surveys re-designed, or resources allocated to
other indicators.
• Experienced aerial surveyors might not always be
available; if inexperienced surveyors are used, the
quality of data may be questionable.
51 .
-------
J
• Indicators such as bird activity (breeding, feeding,
resting) and the presence of threatened, endangered, or
keystone species should be considered to provide more
information about the types of habitat present and its
value to species of interest in a particular region.
• A plan for data integration, and reduction should be
designed for summarizing results of multiple surveys.
Analysis by taxonomic group (e.g., waterfowl, shorebirds,
passerine's) or feeding guildsi should also be considered
for a more detailed assessment of habitat quality.
• Logistics and QA issues involved in coordinating bird
surveys with other agencies, universities, or
organizations, and conflicts that might arise due to
diverging interests in the kinds of data collected should
be anticipated.
• Surveys should be conducted at nearby non-WTS reference
wetlands, or habitat quality criteria should be developed
for use as a "gauge" when making habitat quality
assessments.
A method for rapid estimation of the habitat importance of
specific wetlands is currently being developed and tested by Adamus
(1993) and may prove useful when many wetlands are being assessed
on a regular basis. The procedure, which emphasizes biodiversity
and an ecosystems approach, estimates the number of bird species
likely to occur regularly in a particular wetland and uses this to
assign importance to the wetland. Development of a procedure such
as this for use in WTS may be a feasible alternative to traditional
bird surveys.
Site Morphology
Diversity, abundance, and density of wetland-dependent animals
is usually higher when vegetation and water are well-interspersed
(Steel et al. 1956, Weller and Frederickson 1973). Weller and
Frederickson (1973) concluded that marshes with 50-70 percent open
water that is well interspersed with emergent vegetation (or a
ratio of water to cover of 1.00-2.33) produced the highest bird
diversities and numbers. Weller and Spatcher (1965) noted that
maximum bird species richness and abundance occurred when a well-
interspersed water:cover ratio of 50:50 (or 1.00) existed. Based
on these findings, the most optimal ratios of open water to
vegetated area occurred in the lake at the Orlando site (ratio of
1.59) and in cells 5 and 6 at the Lakeland site (ratios of 1.05 and
1.29, respectively) (Table 16). Some of the land:water ratios at
the Orlando site and in cell 3 at the Lakeland site, however, may
be biased low because areas of small floating-leaved plants were
not considered to be open water when the GIS analysis was done.
52
-------
Cells 1 and 2 at the Lakeland site were almost entirely vegetated,
primarily with scrub/shrub. ,
The open water category primarily describes large expanses of
open water with no vegetation (i.e., those that are visible on
photos); it is not the total amount of water present. Waterbirds
can use 'areas covered by small floating-leaved plants and areas
under the canopies of shrubs, trees, and large emergent plants,
such as Typha and Scirpus. At both of the WTS, surface water
underneath other vegetation, but not visible on photographs, was
sufficient to allow use by waterbirds for protection and feeding.
These-areas, particularly abundant in the forested areas at the
Orlando site, provided habitat for a diversity of birds.
Land/water interface per hectare is a measure of edge. It is
also another measure of the degree of interspersion of water and
cover. Harris and others (1983) concluded that edge habitat is
important to bird species diversity. Numerous dikes at both sites
and ^ islands at the Lakeland sjlte contribute to the amount of edge
habitat available. The amount of land/water interface in relation
to wetland area, however, is relatively low, averaging only 107.0
m/ha at the Orlando site and 67.0 m/ha at the Lakeland site. This
is a result of the large area of most cells at both WTS in relation
to shoreline. Although no land/water interface data were available
from non-WTS for comparison, the landrwater interface of two.WTS
studied in Mississippi were 410 and 230 m/ha (McAllister 1992) .
These WTS had construction similar to the Florida WTS but were much
smaller. The incorporation of peninsulas, islands, or additional
cells in the design of large WTS would result in a greater amount
of shoreline per unit area of wetland.
The interface between different cover types is another measure
of interspersion and edge. Wetlands with moderate to high
vegetation richness and interspersion can support a greater density
and species richness of aquatic animals than those with low
interspersion (Weinstein and Brooks 1983, Rozas and Odum 1987).
Weller and Spatcher (1965) noted that many marsh bird species
nested near water-cover interfaces or the interface of two cover
types. At the two WTS, plant species were observed to be diverse
and well-interspersed. Plant communities have been allowed to
develop naturally at the Lakeland site. Plant communities in the
mixed marsh and hardwood swamp communities at the Orlando site are
managed to provide wildlife habitat diversity. The. cover/cover
interface in these communities at the Orlando site was 387.4 m/ha
and 443.7 m/ha, respectively, which is higher than the deep marsh,
the lake, and the overall site. The cover/cover interface per ha
was also very high in cell 4 at the Lakeland site (499.1 m/ha)
(Table 16) . The cover/cover ratio in Cell 5, which contains the
bird rookeries, was 373.1, which is also high relative to the
overall site.
The large areas of both WTS indicate that the sites have
53
-------
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potential to provide many of the habitat requirements of birds.
Because wetlands are numerous in the southeastern United States'
however, it is not essential that the WTS provide all the habitat
requirements of wildlife. Large wetlands or complexes of wetlands
types and upland areas may be necessary for fulfilling all wildlife
needs or for attracting birds (Weller 1978). Birds, in particular
can move between different wetlands (i.e., within a wetland
complex) , using certain locales for nesting, feeding, roosting and
cover. The habitat value of the Orlando WTS, for example, is
likely increased because of its setting adjacent to the St. Johns
Marshes, a productive feeding area for wading birds in central
Florida. Site morphology indicators might provide more information
if calculated for a complex of wetlands in a watershed or within a
chosen distance from the wetland in question so that single
wetlands can be assessed in the landscape context and not as
isolated entities. The landscape setting and its influence on
wildlife habitat quality is also a very important consideration
when choosing the most appropriate construction site for a WTS.
The use of aerial photographs for obtaining site morphology
indicators is highly recommended for future assessment and
monitoring. Aerial photography can easily be arranged through
regional photographic companies as long as photo specifications are
clearly defined. Photographs should be timed to coincide with
field sampling of other indicators. This is often problematic,
particularly in the southeastern U.S., because late summer haze
obstructs visibility and photo quality. Photographers often will
not fly on hazy days, which can potentially delay photography until
autumn.
• Physical habitat features such as shoreline length, amount of
edge, ratio of open water to vegetated area, and vegetation
interspersion and structural diversity are good indicators of
habitat quality because their relationships to wildlife production
and/or use have been demonstrated. Data interpretation is
therefore facilitated by using guidelines found in the literature.
Site morphology measurements can be obtained from maps or aerial
photographs in a relatively short time and with less effort than
field work. They can be taken in every wetland of interest, and
replicate samples and assessment of variability are not necessary.
Some field ground truthing of vegetation types, however, is
necessary for air photo interpretation.
Aerial photos and maps can also be used to evaluate the larger
landscape setting, which is of great importance in evaluating
wildlife habitat. Photo interpretation and field sampling should
be _used interactively to maximize the information obtained.
Estimation of the dominant structural layers can be obtained from
photos while field work might focus on gathering data on cover
.types and species richness. Methods for evaluating vegetative
structure using aerial photographs have been described (Short and
Williamson 1986) and may be adaptable for WTS. One limitation of
using landscape indicators is the high cost of aerial photography
Current existing photos, if available, may be an alternative.
57
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Water Quality
Water quality can influence the biological components of
wetland systems, such as plant and animal abundance and species
diversity. Water quality data are presented for both WTS in Table
17. With the exception of total phosphorus at the Lakeland site,
water quality values are generally within the range of values for
non-WTS, and there is some indication that water quality at the WTS
is superior to that in non-WTS in the southeastern U.S. Both WTS
have achieved permitted effluent requirements (Jackson 1989).
There is evidence from data collected at the Orlando site that
nutrient concentrations lower than those attained through
conventional advanced waste treatment processes can be achieved in
WTS (Swindell and Jackson 1990) .
Average TSS concentrations at the two WTS ranged from 5.02 to
8.10 mg/L. The lowest concentration recorded was <0.02 mg/L in the
effluent at the Orlando site. Neither site ever had' TSS
concentrations over 21 mg/L, and the TSS concentrations were
reduced from the influent to the effluent points (Table 17). For
comparison, TSS concentrations in non-WTS wetlands near the lower
Mississippi River and in created and natural marshes in central
Florida ranged from 1.0-25.7 mg/L (Tables 18 and 19). Values at
the WTS fell within the lower part of this range, and the lowest
WTS concentration was lower than any of the values found for non-
WTS. Wetlands that receive water with TSS levels less than 80 mg/L
and never more than 200 mg/L are more likely to support a greater
diversity and/or abundance of fish and invertebrates (Adamus,
personal communication, ManTech Environmental Technology, Inc.,
Corvallis, OR). The two WTS clearly fall into this category. :
Average DO concentrations at the WTS ranged from 1.47 to 8.09
mg/L (Table 17) . The average concentration dropped by over 3 mg/L
between the influent and effluent at the Orlando site and increased
only slightly from the influent to the effluent ends of the
Lakeland WTS. Average DO concentrations for non-WTS ranged from
1.0 to 12.1 mg/L (Tables 18, 20, 21, 22). Most non-WTS values,
however, were between 2 and 8 mg/L, and some of the highest of
those were recorded in abandoned channel and oxbow lakes (Table
18). The average effluent DO of 1.47 mg/L at the Orlando site is
low in comparison to other wetlands in the region and does not meet
the site permit requirement of 3.5 mg/L (Jackson 1989), even when
the standard deviation is added. Dissolved oxygen concentrations
of 2 and 4 mg/L are common in many Florida streams and swamps
(Dierberg and Brezonik 1984, Friedemann and Hand 1989, Hampson,
1989). Consequently, low DO often naturally limits the richness of
invertebrates (Ziser 1978) and fish (Tonn and Magnuson 1982) in
wetlands. There was no evidence from this study, however, that the
richness of aquatic life was limited at the Orlando site.
58
-------
Table 17. Summaries of water quality data at the Orlando and
Lakeland sites. I=influent; E=effluent; N=number of
samples; Substandard units; TSS=total suspended solids;
DO=dissolved oxygen; BOD=biochemical oxygen demand (5-
day) ; NH3-N=ammonia nitrogen; TKN=total Kjeldahl
nitrogen; TP=total phosphorus; Fee.Col.-fecal' coliform
bacteria. Standard error was calculated at the Lakeland
site because the values used to calculate means• were
monthly averages.
Variable I/E N
pH Not measured
pH Not measured
TSS (mg/L) I 72
TSS E 71
DO (mg/L) I 51
DO E 69
BOD (mg/L) I 71
BOD E 71
ORLANDO
Range
Mean
Std Dev
NH3-N (mg/L) I 71
NH3-N E 71
TKN (mg/L) I 70
TKN E 71
TP (mg/L) I 71
TP E 71
Fee.Col. I 71
(no./lOO mL)
Fee.Col. E 70
1.80-17.00
0.10-20.60
0.20-11.60
0.01- 6.00
0.30-32.20
0.20- 5.00
0.05- 8.74
0.00- 0.80
0.59- 9.10
0.32- 1.64
0.15- 3.30
0.02- 0.24
0.00-75.00
0.00-180.00
8.10
5.02
4.72
1.47
4.57
2.36
2.36
0.11
3.15
0.91
0.68
0.08
5.66
53.26
3.83
4.66
3.38
1.68
4.62
1.08
1.97
0.15
2.07
0.22
0.50
0.04
11.99
43.19
59
-------
-^."'-'-il^j'iirt^
(Table 17, continued) [
•
Variable
pH (S.U.)
pH
TSS (mg/L)
TSS
DO (mg/L)
DO
BOD (mg/L)
BOD
NH3-N (mg/L)
NH3-N
TKN (mg/L)
TKN
TP (mg/L)
TP
Fee . Col .
(no./100 mL
Fee . Col .
I/E
I
E
I
E
I
E
I
E
I
E
I
E
I
E
I
)
E
• H
19
19
19
19
19
19
19
19
19
19
19
19
19
19
7
7
LAKELAND
Range
7.10- 7.50
7.60- 8.40
2.00-14.00
4.00- 9.00
6.50- 9.80 ;
6.20-10.50
3.00- 8.00
3.00- 6.00
0.20- 4.35
0.06- 0.30
2.20- 5.90
0.96- 1.88
5.70-13.05
1.97- 5.02
1.00- 2.00
17.00-61.00
Mean
7.33
7.97
7.68
6.00
7.92
8.09
4.74
3.89
1.36
0.17
3.46
1.42
8.36
4.15
1.14
33.43
Std Err
*
*
0.75
0.30
0.19
0.26
0.34
0.20
0.25
0.02
0.30
0.06
0.42
0.19 ;
0.14 ;
6.48
* pH means were calculated by taking the log of the average
hydrogen ion concentration; standard errors were not considered
meaningful.
60
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Table 18. Surface (0.3 m depth) water quality means, ranges, and sample
sizes from eight Lower Mississippi River non-WTS abandoned
" channel and oxbow lakes, 1984 (Lowery et al/, 1987) pH in
standard^ units, DO (dissolved oxygen and TSS (total suspended
solids) in mg/L. Sample sizes were 3 for each measurement at
all lakes except Deer Park, where sample sizes were 6.
pH DO TSS
Canadian Reach 6.9 6.3 10.7
6.8-7.1 4.8-7.4 9.0-13.0
Crutcher Lake 7.9 7.6 13.7
7.5-8.2 5.7-8.9 6.0-29.0
Catfish Chute 7.7 4.5 8.0
7.6-7.8 3.0-6.7 6.0-12.0
Driver Bar 7.6 6.3 5.3
7.4-7.9 4.2-8.4 4.0-6.0
Lake Whittington 7.5 4.9 25.7
7.4-7.5 4.0-5.6 17.0-42.0
Yucatan Lake 7.4 7.0 8.0
7.3-7.6 5.9-7.6 7.0-9.0
Raccourci Lake 7.7 6.2 5.0
7.5-7.8 5.3-6.8 4.0-7.0
Deer Park Lake 7.2 4.6 7.2
7.0-7.4 2.3-6.0 4.0-11.0
61
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Table 19. Water quality in created and natural herbaceous non-WTS
marshes near Tampa, Florida, 1988 (Brown 1991). Values
represent one sample; "a" denotes a duplicate sample.
TSS (total suspended solids), TP (total phosphorus), arid
TKN (total Kjeldahl nitrogen) in mg/L.
TSS TP TKN
Natural Wetlands
107 11.0 0.05 2.20
108 800.0 1.50 15.00
108a 4.0 0.05 2.20
110 66.0 0.11 2.50
201 5.0 0.05 1.90
206 3.0 2.10 6.40
207 270.0 6.10 10.00
207a 280.0 8.70 13.00
Created Wetlands
101 21'. 0 0.42 - 1.40
102 13.0 0.13 1.30
103 10.0 0.06 1.30
103a 13.0 0.05 0.65
104 1.0 0.05 1.20
105 24.0 0.19 ' 2.40
106 20.0 0.18 1.10
204 43.0 0.44 3.90
204a 4.0 0.05 7.50
205 50.0 0.05 1.20 :
208 59.0 0.05 6.60
62
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Average total phosphorus concentrations at the WTS ranged from
0.08 to 8.36 (Table 17). These 'values are within the range of
values found for non-WTS, which ranged from 0.02 to 8.70 mg/L
(Tables 19-22). The mean at the Orlando site fell at the low end
of the range, while the Lakeland site mean was toward the upper end
of the range. Nevertheless, the phosphorus removal rate within the
Lakeland site averaged 50%, which is the expected rate for the
site, based on the original site design (Jackson 1989). Jackson
(1989) reported 60% removal of phosphorus for the first year of
operation at the Lakeland site. Also, the Florida Department of
Environmental Regulation operation permit and the U.S. EPA permit
do not state a limit for total phosphorus because of the nature of
the Lakeland system and because the Alafia River, which receives
effluent from the WTS, is not phosphorus limited (Post, Buckley,
Schuh, and Jernigan, Inc. 1992).
Average fecal coliform bacteria counts at the WTS sites (1.14-
53.26 per 100 mL) (Table 17) fell generally in the lower range of
values reported, for non-WTS (<10-100) (Table 21) . The variability
of fecal coliform data, however, is high at the Orlando site, which
makes comparison difficult.
The average ammonia nitrogen concentrations at the WTS (0.11-
2.36 mg/L) (Table 17) were within or above the range found for non-
WTS, although only four comparison values were found and may not be
completely appropriate because they are from ponds in North
Carolina (Table 21). Average BOD concentrations (2.36-4.74 mg/L)
(Table 17) were in the lower range of values found for non-WTS
(2.3-7.4 mg/L) (Tables 20 and 21). Average TKN values at the WTS
ranged from 0.91 to 3.46 mg/L (Table 17) and fall in the lower
range of values found for non-WTS (0.65-15.00 mg/L) (Tables 19 and
21) .
Interpreting precisely what some water quality indicators mean
for assessing wildlife habitat quality is difficult because the
relationships between water quality and habitat quality are usually
indirect. Water quality influences community composition of
plants, invertebrates, and fish, which are more direct measures of
habitat quality and better integrators of conditions important to
wildlife than is water quality. In addition, the influences of
water quality on habitat are not always consistent. Relationships
between nutrient concentrations and wildlife habitat quality often
are not applicable under a variety of environmental conditions.
In addition, water quality parameters are often variable, and
many measurements must be taken over time to accurately
characterize conditions on the site. In a monitoring program,
available resources and logistics may not permit the number of
measurements required. Use of existing data is also problematic.
The measurements are usually readily available from site operators
because discharge permits require monitoring of certain
constituents in wastewater. However, data management and record-
63
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ro CQ
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6 0S
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rtf E 4->
--H 0) fd
CQ d ,d 4->
m n3 o u ra
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d o E -H m
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rH
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rt
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rH O
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H
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• — •
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0
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O
m
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^
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ro
o
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-- - (£>
cn i
in
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CN i
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vo • «
vo
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d
— m — CN
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64
-------
,-1, - -. ' •
Table 22. Surface water quality mean values for non-WTS marsh sites in
the Okefenokee Swamp (Greening and Gerritsen 1987). pH in
standard units, DO ' (dissolved oxygen) and TP (total
phosphorus) in mg/L. Sample size was not reported. Range is
given for pH and DO; standard error given for TP.
DO TP
Little
Mizell
Mack' s
Cooter Prairie
Prairie
Island Rookery
3
3
3
Reference
3
4
.08
.87-4.53
3
.72
4
.93.
4
.88
.87
-4.15
.17
-4.77
.15
-4.81
5
1.3
4
2.1
2
0.6
2
0.7
.09
-7.
.88
-6.
.50
-7.
.20
-4.
2
6
1
0
0
±0
0
±0
0
±0
0
±0
.021
.006
.031
.013
.052
.031
.020
.002'
keeping by site operators can vary, making it potentially difficult
to acquire specific data and to be certain that all data have been
obtained. There is also some discrepancy among laboratories and
individuals about exactly which metric is measured and what it is
called (e.g., ammonia vs. ammonium, total phosphorus vs. total
phosphorous as phosphate). .
Proper evaluation of acquired data requires review and
evaluation of standard operating and quality assurance procedures
used by Afield crews and each analytical laboratory. This may be
too subjective and lengthy a procedure for routine monitoring.
Interpretation and comparison of data can be difficult if methods,
collection frequencies, or intended uses of the data vary from one
site to another. Because future studies could involve statistical
comparisons, precision and consistency in collection and analysis
methods are important and would be difficult to achieve using
existing data sets. In addition, it is difficult to find non-WTS
for which comparable amounts of existing data are available. For
these reasons, the use of existing water quality data sets is not
recommended. However, sampling of some water quality indicators,
such as dissolved oxygen, ammonia, or suspended solids, during
field sampling might provide information on system stressors. This
information can be used to interpret indicator data collected at
the same time and to determine the reasons for the status of a
particular habitat indicator.
65
-------
CONCLUSIONS AND RECOMMENDATIONS
Based on indicators measured in this study, wetlands used for
treating wastejvater also appear to provide suitable wildlife
habitat in central Florida. Wetland, treatment systems are an
efficient reuse of water for environmental enhancement; they
eliminate some of the chemical treatment; they can be very cost-
effective; and they can be beneficial to wildlife. Wildlife
habitat is most often an ancillary function of WTS, and the
wetlands vary greatly in the habitat values they provide. Much of
the variation can be attributed to whether wildlife habitat
features are considered when the wetlands are designed, funding
available for incorporating specific features, such as islands,
wildlife food plants, irregular shoreline, varying depths, and
vegetation interspersion, and the degree of management and
monitoring of habitats once the wetland is operating.
Table 23 contains a summary of the comparisons between the two
WTS studied and non-WTS in the Southeast. Overall, most of the
indicator values from the two Florida WTS (for which comparison
values were available) were in the mid to high portion of the range
of values for non-WTS. None of the indicator values from the two
WTS studies were below the range of values for non-WTS. With the
exception of ammonia nitrogen, which was at the high end or above
the range, the water quality indicator values were in the low to
mid range of values for non-WTS. Foraging wading bird densities
were higher than densities in some non-WTS in the tropics but were
lower than those in the nearby St. Johns Marshes. The two WTS
appear to be important as breeding habitat for several species of
wading birds, including the endangered wood stork.
The available data suggest that the two WTS provide wildlife
habitat similar or superior in quality to that of non-WTS in the
same region. Habitat quality was assessed in relation to non-WTS
comparison wetlands, but little is known about the habitat quality
of comparison wetlands. Guidelines are needed for selecting
comparison (i.e., reference) wetlands with good wildlife habitat or
for developing criteria for defining good habitat to serve as a
gauge for ranking habitat quality.
A summary of the indicators used in this study, including
sampling effort, expense, reliability of information collected,
direct relevance to wildlife habitat quality, and recommendatiqn
for development in future studies, is given in Table 24.
Vegetation, invertebrate, and site morphology indicators are
recommended for development for evaluating wildlife habitat quality
in WTS. Birds may also be good indicators, but focus should be on
relating bird numbers to habitat quality or on exploring indicators
that may be more informative than bird numbers for assessing
habitat quality, such as bird feeding activity or brood counts.
66
-------
Table 23. General relationship of data from the WTS studied in
Florida to the range of values reported for non-WTS in
the southeast United State's.
Plant Species
Richness
Invertebrate
Genera Richness
Water Nutrient
Concentrations
Bird Species
Richness
Non- breeding
Wading Bird
Density
_
Below
Range
Low
X_
Within
Range
Middle
X
Hiah
'
X
X_
Above
Range
i
Y
A 1
1
1
1
1
|
- - Y 1
A |
1
1
1
Use of existing water quality data was not considered
effective for making general assessments of wildlife . habitat
quality in WTS, and should be given lower priority in future
indicator development. Water quality data can be variable. The
water quality constituents sampled, collection frequencies,
collection methods, and intended uses of the data vary from one
site_to another. Laboratory techniques vary among laboratories,
and information on QC protocols at each laboratory may be time-
consuming to acquire and assess with the same subjectivity in
different geographic areas. Nutrient concentrations do not have
consistent, direct relationships with wildlife habitat quality that
can be applied with certainty under a variety of environmental
conditions. Other indicators, such as vegetation structural
diversity, number of nests, number of singing birds, relative
abundance of wildlife food plants, invertebrate and fish abundance,
and site morphology characteristics are more directly related to
wildlife habitat and may be more reliable indicators.
Toxicity testing can be expensive, particularly beyond the
whole-effluent level of testing. In addition, single, whole-
Affluent tests do not provide time-integrated information,
information about the effects of specific substances in wastewater
on wildlife, or the cause of the problem. The discharge of harmful
substances to WTS is likely a short-term or intermittent event, and
67
-------
1043
0>J
a
•o
M
•rl
|S§2
w °*
•p >1
1 C 4J
4) 4J-H
rH 3 O
O rH-rl
S
.
O
<4H
4)
4J
2
4)
•o
O
e
1
rH
1
Expense
(Sample collect
&
analysis)
moderate
o
low-
moderate
•a
•H
4)
sf
g£
g
X!
•H
*4H O -P
[Reliability o
information f
assessing habi
possibly
0
possibly
in some
cases
a
a
n
&
H a
1 Recommend
development f
future studi<
bird
mobility;
logistics;
contracts
•P ^-P
^ V> S -PrH
5iJ o o 2-ri
^5 rH-H _p 3 A
"»a ?l
i
C
I
,
Ijll
^ 4^ So e
^j «J W B
0)
V
0
C
Problems
68
-------
toxicity in water could be missed by taking only one sample.
-•',**;'• \- - •
^Whole-effluent tests should therefore be conducted on a
routine basis as initial testing for contaminants in selected
wetlands suspected to be at risk from contamination or toxic
inputs, such as wetlands that receive industrial discharges, where
user violations have occurred in the past, or where other data
collected indicate a potential problem requiring further
investigation. Determining the source of any substances found and
making the connections between the levels found and actual effects
on wildlife would then be necessary.
Some topics regarding wildlife habitat quality (e.g., how to
measure it, how to evaluate it) require further study. The
following are suggestions for future studies:
• For comparing WTS with non-WTS, future studies should include
simultaneous sampling on nearby reference (non-WTS) wetlands
so that results from both types of wetlands are more directly
comparable and confounding factors are minimized. It As not
possible to assess collected data if comparison values are
unavailable or unreliable. Comparison with literature values
might be sufficient for preliminary studies, but to put in
context the indicator values from WTS and to make valid
conclusions about the quality of wildlife habitat, the best
data for comparison are those that are collected at the same
time, in close proximity, on similar classes of wetlands, and
with the same sampling techniques.
Reference wetlands should be natural, enhanced, or restored
wetlands that are not used for wastewater treatment. Created
wetlands should not be used for comparisons because there is
not enough information to show that they duplicate wetland
functions on a long-term basis (Kusler and Kentula 1990).
Establishing appropriate criteria for selection of reference
wetlands will require further thought. One approach would be
to establish guidelines for selection of reference sites that
represent "good" habitat quality. Data collected can be used
as a gauge against which measurements or an aggregation of
measurements taken at WTS can be rated. Reference wetlands
should also be as similar as possible to the WTS in question
with respect to size, wetland classification, location, and
type of surrounding land use. Comparisons should be
quantitative.
• In addition to comparison with non-WTS reference sites in the
same_region, guidelines should be developed for rating habitat
quality. ^ In some landscapes, potential reference sites might
all be in marginal or poor condition. Using suboptimal
reference sites as a gauge for assessing habitat quality is
not _ desirable or wise. Although it allows an assessment of
habitat value .relative to the predominant condition in a
69
-------
region, it can weaken the overall concept of good wildlife
habitat. Guidelines should be performance standards that are
applied on the basis of best professional judgment and provide
for. flexibility for dealing with environmental uncertainty
(Chapman 1991).
Future work Should also focus on developing means for
assessing and reducing data. Developing assessment methods
can identify potential stressors,. or causes of condition,
which can then be used to establish a gauge for rating habitat
value. Data reduction involves combining information from a
group of indicators or from data on multiple species to form
a single indicator, or index. For instance, species diversity
incorporates richness and abundance of all species into a
single value. A similar index might be developed for
vegetation structural diversity based on the number of
vegetation layers and their relative coverages. Multivariate
analyses are also useful for analyzing combined data and
forming indices. Species-specific data, however, can be used
to identify stressors or to monitor long term changes at a
wetland and should not be overlooked in favor of indices.
The suite of indicators for this study was limited by level of
funding, labor, and logistical constraints. Future studies
could assess the usefulness of indicators that were not
examined in this study, including new metrics for evaluating
habitat in terms of vegetation, invertebrates, site morphology
and bird use. New indicators might include benthic
invertebrates, basin slope, average water depth, water
permanence, size and configuration of open water areas, and
degree of human disturbance. At this stage, future work
should focus on development of biological indicators that are
directly related to wildlife habitat rather than on attributes
that might only infer wildlife use through an indirect
relation (e.g., nutrients, sediment type, hydrologic regime).
Indirectly-related indicators, however, can be useful for
identifying ecosystem stressors and the reasons for the status
of a particular biological indicator (e.g., hydrologic regime
and sediment types can influence the plant communities that
develop).
If bird use is retained as an indicator, a greater focus
should be placed on bird activity (breeding, feeding,
roosting, resting) in the WTS and the presence of threatened,
endangered, or keystone species.
The elimination of some indicators, if different indicators
provide essentially the same information, would save money and
time in sampling and analysis. For instance, some vegetation
indicators measured in the field can easily be obtained from
air photos (e.g., structural diversity, relative'coverage of
each structural type). Development of remotely-sensed
70
-------
indicators should be further explored, particularly for large
wetlands, such as the two WTS in Florida, where time restricts
thorough ground sampling of the wetland.
This pilot study provided evidence that the two WTS provide
favorable wildlife habitat, comparable to that of non-WTS in the
same geographic region. A dependable water supply at both wetlands
helps ensure permanent, deep water, which makes the sites
attractive as nesting sites for several wading bird species.
Wildlife habitat at both sites has been enhanced while maintaining
effective water treatment, which is evidence that the two interests
are compatible.
71
-------
LITERATURE CITED
Adamus, P.R. 1993. Irrigated Wetlands;of the Colorado Plateau:
Information Synthesis and Habitat Evaluation Method. EPA/600/R-
93/071. U.S. Environmental Protection Agency, Environmental
Research Laboratory, Corvallis, OR.
Adamus, P.R. and K. Brandt. 1990. Impacts on Quality of Inland
Wetlands of the United States: a Survey of Indicators, Techniques,
and Applications of Community-Level Biomonitoring Data. EPA/600/3-
90/073. U.S. Environmental Protection Agency, Environmental
Research Laboratory, Corvallis, OR.
Adamus, P.R., E.J. Clairain, R.D. Smith, and R.E. Young. 1987.
Wetland Evaluation Technique (WET), Vol. II: Methodology. U.S.
Environmental Protection Agency, Environmental Research Laboratory,
Corvallis, OR, and Department of the Army, Vicksburg, MS.
Aust, M.W., S.F. Mader, and R. Lea. 1938. Abiotic changes of a
tupelo-cypress swamp following helicopter and rubber-tired skidder
timber harvest. Fifth Southern Silvicultural Research Conference,
Memphis, TN.
Bancroft, G.T. 1989. Status and conservation of wading birds in
the Everglades. American Birds 43:1258-1265.
Bancroft, G.T., S.D. Jewell, and A.M. Strong. 1991. Foraging arid
nesting ecology of herons in the lower Everglades relative to water
conditions. South Florida Water Management District, West Palm
Beach, FL.
Bancroft, G.T., W. Hoffman, and R. Sawicki. 1992. The importance
of the Water Conservation Areas in the Everglades to the endangered
Wood Stork (Mycteria americana). Conservation Biology 6:392-98.
Bastian, R.K., P.E. Shanaghan, and B.P., Thompson. 1989. Use of
wetlands for municipal wastewater treatment and disposal
regulatory issues and EPA policies. Pages 265-278 IN D.A. Hammer
(Ed.), Constructed Wetlands for Wastewater Treatment: Municipal,
Industrial and Agricultural. Lewis Publishers, Inc., Chelsea, MI.
Beecher, W.J. 1942. Nesting Birds and the Vegetation Substrates.
Chicago Ornithological Society, Chicago, IL.
Brennan, K.M. 1985. Effects of wastewater on wetland animal
communities. Pages 199-223 IN P.J. Godfrey, E.R. Kaynor, S.
Pelczarski, and J. Benforado (Eds.), Ecological Considerations in
Wetlands Treatment of Municipal Wastewaters. Van Nostrand Reinhold
Company, New York, NY.
Brodie, G.A., D.A. Hammer, and D.A. Tomljanovich. 1989. Treatment
of acid drainage with a constructed wetlsind at the Tennessee Valley
72
-------
Authority 950 Coal Mine. Pages 201-209 IN D.A. Hammer (Ed.),
Constructed Wetlands for Wastewater Treatment: Municipal',
Industrial and Agricultural. Lewis 'Publishers, Inc., Chelsea, Ml!
Brooks, R.P., D.E. Arnold, E.D. Bellis,. C.S. Keener, and M.J.
Croonquist._ 1989. A methodology for biological monitoring of
cumulative impacts on wetland, stream, and riparian components of
watersheds. Proceedings of the International Wetlands Symposium,
Charleston, SC. Association of State Wetland Managers, Inc.,
Berne, NY.
Brooks, R.P. and R.M. Hughes. 1988. Guidelines for assessing the
biotic communities of freshwater wetlands. Pages 276-282 IN J.'A.
Kusler, M.L. Quammen, and G. Brooks (Eds.), Proceedings of the
National Wetland Symposium: Mitigation of Impacts and Losses.
Association of State Wetland Managers, Berne, NY.
Brown, M.T. 1991. Evaluating Created Wetlands through comparisons
with natural wetlands. EPA/600/3-91/058. U.S. Environmental
Protection Agency, Environmental Research Laboratory, Corvallis,
OR.
Brown, M.T., J. Schaefer, and K. Brandt. 1989. Buffer zones for
water, wetlands, and wildlife in the east central Florida region.
Center for Wetlands, University of Florida, Gainesville, FL.
Buglewitz, E.G., W.A. Mitchell, J.E. Scott, M. Smith, and W.L.
King. 1988. A physical description of main stem levee borrow pits
along the lower Mississippi River. U.S. Army Corps of Engineers,
Mississippi River Commission, Vicksburg, MS.
Cedarquist, N.W. 1979. Suisun Marsh management study, progress
report on the feasibility of using wastewater for duck club
management. U.S. Department of Energy, Water and Power Resources
Service, Sacramento, CA.
Cedarquist, N.W. 1980a. Suisun Marsh management study, progress
report on the feasibility of using wastewater for duck club
management. U.S. Department of Interior, Water and Power Resources
Service, Sacramento, CA.
Cedarquist, N.W. 1980b. Suisun Marsh management study, 1979-1980
progress report on the feasibility of using wastewater for duck
club management. U.S. Department of Interior, Water and Power
Resources Service, Sacramento, CA.
Cedarquist, N.W. and W.M. Roche. 1979. Reclamation and reuse of
wastewater in the Suisun Marsh of California. Proceedings of the
Water Reuse Symposium, Vol. 1. American Water Works Association
Research Foundation, Denver, CO.
Chapman, P.M. 1991. Environmental quality criteria: what type
73 •
-------
should we be developing? Environmental Science and Technology
25:1353-1359.
Cobb, S.P., C.H. Pennington, J.A. Baker, and J.E. Scott. 1984.
Fishery and ecological investigations of main stem levee borrow
pits along the lower Mississippi River. U.S. Army Corps of
Engineers, Mississippi River Commission, Vicksburg, MS.
Conway, T.E. and J.M. Murtha. 1989. The Iselin Marsh Pond Meadow.
Pages 139-144 IN D.A. Hammer (Ed.), Constructed Wetlands for
Wastewater Treatment: Municipal, Industrial and Agricultural.
Lewis Publishers, Inc., Chelsea, MI.
Costello, C.J. 1989. Wetlands treatment of dairy animal wastes in
Irish drumlin landscape. 'Pages 702-709 IN D.A. Hammer (Ed.),
Constructed Wetlands for Wastewater Treatment: Municipal,
Industrial and Agricultural. Lewis Publishers, Inc., Chelsea, MI.
Cyr, H. and J.A. Downing. 1988. Empirical relationships of
phytomacrofaunal abundance to plant biomass and macrophyte bed
characteristics. Canadian Journal of Fisheries and Aquatic
Sciences 45:976-984.
Davis, D.G. and J.C. Montgomery. 1987. EPA's regulatory and policy
considerations on wetlands and municipal wastewater treatment.
Pages 69-70 IN K.R. Reddy and W.H. Smith (Eds.), Aquatic Plants for
Water Treatment and Recovery. Magnolia Publishing Inc., Orlando,
FL.
Demgen, F.C. 1979. Wetlands creation for habitat and treatment at
Mt. View Sanitary District, California. Pages 61-73 IN R.K.
Bastian and S.C. Reed (Project Officers), Aquaculture Systems for
Wastewater Treatment: Seminar Proceedings and Engineering
Assessment. EPA 430/9-80-006. U.S. Environmental Protection
Agency, Office of Water Program Operations, Municipal Construction
Division, Washington, DC.
Demgen, F.C. and J.W. Nute. 1979. Wetlands creation using
secondary treated wastewater. Pages 727-739 IN American Water
Works Association Research Foundation Water Reuse Symposium, Vol.
I. American Water Works Association Research Foundation,
Washington, DC.
Dickerman, J.A., A.J. Stewart, and J.C. Lance. 1985. The impact of
wetlands on the movement of water and nonpoint pollutants from
agricultural watersheds. A report to the Soil Conservation
Service. U.S. Department of Agriculture, Agricultural Research
Service, Water Quality and Watershed Research Laboratory, Durant,
OK.
Dierberg, F.E. and P.L. Brezonik. 1984. Water chemistry of a
Florida cypress dome. Pages 34-50 IN K.C. Ewel and H.T. Odum
(Eds.), Cypress Swamps. University Presses of Florida, Gainesville,
74
-------
FL. -
Donovan, D.B. 1990a. First"Annual Report, Monitoring of Wetland
Vegetation at IMCF Section 12 Hookers Prairie Reclamation Site Polk
County, FL. IMC Fertilizer, Inc., Bartow FL.
Donovan, D.B. 1990b. Forth Annual Report, N.E. 7/12 Reclaimed
Stream. IMC Fertilizer, Inc., Bartow, FL.
Dvorak, J. andE.P.H. Best. 1982. Macroinvertebrate communities
associated with the macrophytes of Lake Vechten: structural and
functional relationships. Hydrobiologia 95:115-26.
Dwyer, T. J., G. L Krapu, and D. M. Janke. 1979. Use of prairie
pothole habitat by breeding mallards. Journal of Wildlife
Management 43:526-531.
Edelson, N.A. and M.W. Collopy. 1990. Foraging ecology of wading
birds using an altered landscape in central Florida. Florida
Institute of Phosphate Research, Bartow, FL.
Erwin, K.L. 1988. Fort Green Reclamation Project, 6th annual
report for Agrico Chemical Company, Mulberry, FL. Erwin Consulting
Ecologist, Inc., Fort Myers, FL.
Erwin, K.L. 1990. Payne Creek Reclamation Project, 3rd annual
report for Agrico Chemical Company, Mulberry, FL. Erwin Consulting
Ecologist, Inc., Fort Myers, FL.
Erwin, K.L. 1991. An evaluation of wetland mitigation in the South
Florida Water Management District - Volume II. Report to South
Florida Water Management District, West Palm Beach, FL. Fort
Myers, FL.
Erwin, K.L. and F.D. Bartleson. 1985. Water quality within a
central Florida phosphate surface mined reclaimed wetland. Pages
74-85 IN F.J. Webb (Ed.), Proceedings of the Twelfth Annual
Conference on Wetland Restoration and Creation. Hillsborough
Community College, Tampa,. FL.
Erwin, K.L. and G.R. Best. 1985. Marsh community development in a
central Florida phosphate surface-mined reclaimed wetland
Wetlands 5:155-66.
Fetter, C.W., Jr., W.E. Sloey, and F.L. Spangler. 1978. Use of a
natural marsh for wastewater polishing.- Journal of the Water
Pollution Control Federation 50:290-307.
Frederick, P.C. and M.W. Collopy. 1988. Reproductive ecology of
wading birds in relation to water conditions in the Florida
Everglades. Florida Fish and Wildlife Cooperative Research Unit
Technical Report No. 30. U.S. Fish and Wildlife Service,
Gainesville, FL.
75
-------
Friedemann, M. and J. Hand. 1989. Typiccil water quality values for
Florida's lakes, streams and estuaries. Florida Department of
Environmental Regulation, Tallahassee, FL.
Greening, H.S. and J. Gerritsen. 1987. Changes in macrophyte
community structure following drought in the Okefenokee Swamp,
Georgia, U.S.A. Aquatic Biology 28:113-128.
Godfrey, P.J., E.R. Kaynor, S. Pelczarski, and J. Benforado (Eds.).
1985. Ecological Considerations in Wetlcinds Treatment of Municipal
Wastewaters. Van Nostrand Reinhold Company, New York, NY. ',
Guntenspergen, G.R. and F. Stearns. 1985. Ecological perspectives
on wetland systems. Pages 69-97 IN P.J. Godfrey, E.R. Kaynor, S.
Pelczarski, and J. Benforado (Eds.), Ecological Considerations in
Wetlands Treatment of Municipal -Wastewaters. Van Nostrand Reinhold,
New York, NY.
Hammer, D.A. and R.K. Bastian. 1989. Wetlands ecosystems: natural
water purifiers? Pages 5-19 IN D.A. Hammer (Ed.), Constructed
Wetlands for Wastewater Treatment: Municipal, Industrial and
Agricultural. Lewis Publishers, Chelsea, MI.
Hampson, P.S. 1989. Dissolved oxygen concentrations in a central
Florida wetlands stream. Pages 149-159 IN D.W. Fisk (Ed.),
Proceedings of the Symposium on Wetlands: Concerns and Successes,
Tampa, FL. American Water Resources Association, Bethesda, MD.
Harris, H.J., M.S. Milligan, and G.A. Fewless. 1983. Diversity:
quantification and ecological evaluation in freshwater marshes.
Biological Conservation 27:99-110.
Henigar and Ray Engineering Associates, Inc. 1990. A qualitative
and quantitative assessment of the West-6f-K6 reclamation unit,
Hillsborough County, FL. Prepared for IMC Fertilizer, Inc.,
Bartow, FL.
Hicks, D.B. and Q.J. Stober. 1989. Monitoring of constructed
wetlands for wastewater. Pages 447-455 IN D.H. Hammer (Ed.),
Constructed Wetlands for Wastewater Treatment, Municipal,
Industrial and Agricultural. Lewis Publishers, Inc., Chelsea, MI.
Hoffman, W., G.T. Bancroft, and R.J. Sawicki. 1990. Wading bird
populations and distributions in the Water Conservation Areas of
the Everglades: 1985-1988. South Florida Water Management
District, West Palm Beach, FL.
Hunsaker, C.T. and D.E. Carpenter, Eds. 1990. Ecological
indicators for the Environmental Monitoring and Assessment Program.
•U.S. Environmental Protection Agency, Atmospheric Research and
Exposure Laboratory, Research Triangle,Park, NC.
76
-------
Jackson, J. 1989. Man-made wetlands for wastewater treatment: two
case studies. Pages 574-580 IN D.A. Hammer (Ed.), Constructed
Wetlands for Wastewater Treatment:' Municipal, Industrial, and
Agricultural. Lewis Publishers, Inc., Chelsea, MI.
Jeffries, M. 1989. Measuring Tailing's element of chance in pond
populations. Freshwater Biology 20 : 383-93 .
Jelks, H. 1991. The distribution of foraging wading birds in
relation to the physical and biological characteristics of
freshwater wetlands in southwest Florida. MS Thesis, University of
Florida, Gainesville, FL.. '
Kadlec, R.H. and F.B. Bevis. 1990. Wetlands and wastewater:
Kinross, Michigan. Wetlands 10(l):77-92.
Kadlec, R.H. and J.A. Kadlec. 1979. Wetlands and water quality.
Pages 436-456 IN P.E. Greeson, J.R Clark, and J.E. Clark (Eds.),
Wetland Functions and Values: The State of Our Understanding.
American Water Resources Association, Minneapolis, MN.
King County. 1986. The Use of Wetlands for Stormwater Storage and
Nonpoint Pollution Control: A Review of the Literature. Resource
Planning Section, Department of Planning and Community Development,
King County, WA.
Krull, J.N. 1970. Aquatic plant macroinvertebrate associations and
waterfowl. Journal of Wildlife Management 34:707-718.
Kusler, J.A. and M.E. Kentula (Eds.). 1990. Wetland Creation and
Restoration: The Status of the Science. Island Press, Washington,
DC.
Lowery, D.R., M.P. Taylor* R.L. Warden, and F.H. Taylor. 1987.
Fish and benthic communities of eight lower Mississippi River
floodplain lakes. Lower Mississippi River Environmental Program
Report 6. Mississippi River Commission, Vicksburg, MS.
MacPherson, T.F. 1988. Benthic macroinvertebrates of selected
ponds in the Nags Head Woods Ecological Preserve. The Association
of Southeastern Biologists Bulletin 35 (4) : 181-188.
McAllister, L.S. 1992. Habitat quality assessment of. two wetland
treatment systems in Mississippi - A pilot study. EPA/600/R-92-
229. U.S. Environmental Protection Agency, Environmental Research
Laboratory, Corvallis, OR.
McAllister, L.S. 1993. Habitat quality assessment of two wetland
treatment systems in the arid West - A pilot study. EPA/600/R-93-
117. U.S. Environmental Protection Agency, Environmental Research
Laboratory, Corvallis, OR.
Merritt, R.W. and K.W. Cummins (Eds.). 1984. An Introduction to
77
-------
the Aquatic Insects of North America, Second Edition. Kendall/Hunt
Publishing Company, Dubuque, IA.
Mudroch, A. and J.A. Capobianco. 1979. Effects of treated effluent
on a natural marsh. Journal of Water Pollution Control Federation
51(9):2243-2256.
Murkin, H.R. and B.D.J. Batt. 1987. Interactions of vertebrates
and invertebrates in peatlands and marshes. Memoirs of the
Entomological Society of Canada Vol. 40.
Murkin, H.R. and D.A. Wrubleski. 1987. Aquatic invertebrates of
freshwater wetlands: function and ecology. Pages 239-49 IN D.D.
Hook, W.H. McKee Jr., H.K. Smith, J. Gregory, V.G. Burell, Jr.,
M.R. DeVoe, R.E. Sojka, S. Gilbert, R. Banks, L.H. Stolzy, D.
Brooks, T.D. Matthews and T.H. Shear (Eds.), The Ecology and
Management of Wetlands, Vol. I: Ecology of Wetlands. Groom Helm,
London.
Nixon, S.W. and V. Lee. 1986. Wetlands and water quality: a
regional view of recent research in the United States on the role
of freshwater and saltwater wetlands as sources, sinks, and
transformers of nitrogen, phosphorus, and various heavy metals.
Technical Report Y-86-2. U.S. Army Corps of Engineers, Vicksburg,
MS.
Pennak, R.W. 1978. Freshwater Invertebrates of the United States.
Second Edition. John Wiley and Sons, Inc., New York, NY.
Piest, L.A. and L.K. Sowls. 1985. Breeding duck use of a sewage
marsh in Arizona. Journal of Wildlife Management 49:580-585.
Plafkin, J.L., M.T. Barbour, K.D. Porter, S.K. Gross, and R.M.
Hughes. 1989. Rapid bioassessment protocols for use in streams and
rivers: benthic macroinvertebrates and fish. EPA/444/4-89-001.
U.S. Environmental Protection Agency, Office of Water, Washington,
DC.
Post, Buckley, Schuh, and Jernigan, Inc. 1992. Performance Review
for City of Lakeland's Glendale Wetland Treatment System:
Monitoring report for years 1987 through 1991. Prepared for City
of Lakeland Department of Public Works. PBS&J, Winter Park, FL.
Rapport, D.J. 1989. What constitutes ecosystem health?
Perspectives in Biology,and Medicine 33(1):120-132.
Reed, S.C., E.J. Middlebrooks, and R.W. Crites. 1988. Natural
Systems for Waste Management and Treatment. McGraw-Hill, New York,
NY.
Reid, F.A. 1985. Wetland invertebrates in relation to hydrology
and water chemistry. Pages 72-79 IN M.D. Knighton (Ed.)., Water
Impoundments for Wildlife: a Habitat Management Workshop. General
78
-------
Technical Report NC-100. North Central Forest Experiment Station
St. Paul, MN.
Richardson, C.J. and D.S, Nichols. 1985. Ecological analysis of
wastewater management criteria in wetland ecosystems. Pages 351-
391 IN P.J. Godfrey, E.R. Kaynor, S. Pelczarski, and J. Benforado
(Eds), Ecological Considerations in Wetlands Treatment of Municipal
Wastewaters. Van Nostrand Reinhold Company, New York, NY.
Roth, R.R. 1976. Spatial heterogeneity and bird species diversity.
Ecology 57:773-82.
Rozas, L.P., and W.E. Odum. 1987. The role of submerged aquatic
vegetation in influencing the abundance of nekton on contiguous
tidal freshwater marshes. Journal of Experimental Marine Biology
and Ecology 114:289-300.
Ruwaldt, J.J., Jr., L.D. Flake, and J.M. Gates. 1979. Waterfowl
pair use of natural manmade wetlands in South Dakota. Journal of
Wildlife Management 43:375-383.
Sather, J.H. 1989. Ancillary benefits of wetlands constructed
primarily for wastewater treatment. Pages 353-358 IN D.A. Hammer
(Ed.), Constructed Wetlands for Wastewater Treatment: Municipal,
Industrial and Agricultural. Lewis Publishers, Inc., Chelsea, MI.
Schaeffer, D.J., E.E. Herricks, and H.W. Kerster. 1988. Ecosystem
health I: measuring ecosystem health. Environmental Management
12 (4) :445-455.
Schwartz, L.N. 1987. Regulation of wastewater discharge to Florida
wetlands. Pages 951-958 IN K.R. Reddy and W.H. Smith (Eds.),
Aquatic Plants for Water Treatment and Resource Recovery. Magnolia
Publishing, Inc., Orlando, FL.
Short, H.L. and S.C. Williamson. 1986. Evaluating the structure of
habitat for wildlife. Pages 97-104 IN J. Verner, M.L. Morrison,
and C.J. Ralph (Eds.), Wildlife 2000: modeling habitat
relationships of terrestrial vertebrates. University of Wisconsin
Press, Madison, WI.
Smith, B.D., P.S. Maitland, andS.M. Pennock. 1987. A comparative
study of water level regimes and littoral benthic communities in
Scottish Locks. Biplogical Conservation 39:291-316.
Staubitz, W.W., J.M. Surface, T.S. Steenhuis, J.H. Peverly, M.J.
Lavine, N.C. Weeks, W.E. Sanford, andR.J. Kopka. 1989. Potential
use of constructed wetlands to treat landfill leachate. Pages 735-
742 IN D.A. Hammer (Ed.), Constructed Wetlands for Wastewater
Treatment: Municipal, Industrial and Agricultural. Lewis
Publishers, Inc., Chelsea, MI.
Steel, P.E., P.D. Dalke, and E.G. Bizeau. 1956. Duck production at
79
-------
Gray's Lake, Idaho, 1949-51. Journal of Wildlife Management
20:279-85.
Swanson, G.A. and M.I. Meyer. 1977. Impact of fluctuating water
levels on feeding ecology of breeding blue-winged teal. Journal of
Wildlife Management 41:426-433.
Swift, B.L., J.S. Larson, and R.M. DeGraaf. 1984. Relationship of
breeding bird density and diversity to habitat variables in
forested wetlands. Wilson Bulletin 96:48-59.
Swindell, C.E. and J.A. Jackson. 1990. Constructed wetlands design
and operation to maximize nutrient removal capabilities. Pages
107-114 IN P.P. Cooper and B.C. Findlater (Eds.), Constructed
Wetlands in Water Pollution Control. Pergamon Press, Oxford, NY.
Teels, B.M., G. Anding, D.H. Arner, E.D. Norwood, and D.E. Wesley.
1976. Aquatic plant, invertebrate and waterfowl associations in
Mississippi. Proceedings of the Southeast Association of Game Fish
Commission 30:610-616.
Tonn, W.M. and J.J. Magnuson. 1982. Patterns in the species
composition and richness of fish assemblages in northern Wisconsin
lakes. Ecology 63:1149-1166.
Tucker, D.S. 1958. The distribution of some fresh-water
invertebrates in ponds in relation to annual fluctuations in the
chemical composition of the water. Journal of Animal Ecology
27:105-119.
U.S. Army Engineer Mississippi River Commission. 1986. Bird and
Mammal Use of Main Stem Levee Borrow Pits along the Lower
Mississippi River. Lower Mississippi River Environmental Program
Report 3, Vicksburg, MS.
U.S. Environmental Protection Agency. 1983. The Effects of
Wastewater Treatment Facilities on Wetlands in the Midwest.
Appendix A: Technical Support Document. USEPA-905/3-83-002. 'U.S.
Environmental Protection Agency, Region 5, Chicago, IL.
U.S. Environmental Protection Agency. 1984. The Ecological Impacts
of Wastewater on Wetlands, An Annotated Bibliography. EPA 905/3-84-
002. U.S. Environmental Protection Agency and U.S. Fish and
Wildlife Service, Washington, DC.
s
U.S. Environmental Protection Agency. 1988a. Design Manual:
Constructed Wetlands and Aquatic Plant systems for Municipal
Wastewater Treatment. EPA/625/1-88/022. U.S. Environmental
Protection Agency Center for Environmental Research Information,
Cincinnati, OH.
U.S. Environmental Protection Agency. 1988b. Short-t'erm Methods
for Estimating the Chronic Toxicity of Effluents and Receiving
80
-------
Waters to Marine and Estuarine Organisms. EPA-600/4-87-028.
Environmental Monitoring and Support Laboratory, Cincinnati, OH.'
U.S. Fish and Wildlife Service. 1980. Habitat Evaluation
Procedures (HEP) Manual (102ESM). U.S. Fish and Wildlife Service,
Washington, DC.
Vannote, R.L., G.W.- Minshall, K.W. Cummins, J.R. Sedell, and C.E.
Gushing. 1980. The river continuum concept. Canadian Journal of
Fisheries and Aquatic Sciences 37:130-137.
Voights, D.K. 1976. Aquatic invertebrate abundance in relation to
changing marsh conditions. American Midland Naturalist 95:313-322.
Wallace, P.M. 1990. Herbaceous vegetation monitoring of the IMC
Horse Creek wetland reclamation site. IMC Fertilizer, Inc.,
Bartow, FL.
Weinstein, _M.P. and H.A. Brooks. -1983. Comparative ecology of
nekton_ residing in a tidal creek and adjacent seagrass meadow:
community composition and structure. Marine Ecology Progress Series
12:15-17.
Weller, M.W. 1978. Management of freshwater marshes for wildlife.
Pages 267-84 IN R.E. Good, D.F. Whigham, and R.L. Simpson (Eds.),
Freshwater Wetlands: Ecological Processes and Management Potential.
Academic Press, New York, NY. :
Weller, M.W. and L.H. Frederickson. 1973. Avian ecology of a
managed glacial marsh. Living Bird 12:269-91.
Weller, M.W. and C.E. Spatcher. 1965. Role of habitat in "the
distribution and abundance of marsh birds. Special Report No. 43.
Iowa Agricultural Home Economics Experiment Station, Ames, IA.
Wilhelm, M. , S.R. Lawry, and D.D. Hardy. 1988. Creation and
management of wetlands using municipal wastewater in northern
Arizona: a status report. Pages 114-120 IN J. Zelazny and J.S.
Feierabend (Eds.), Increasing Our Wetland Resources. National
Wildlife Federation, Washington, DC. • .
Yocum, T.G., R.A. Leidy, and C.A. Morris. 1989. Wetlands
protection through impact avoidance: A discussion of the 404(b)(1)
alternatives analysis. Wetlands 9(2):283-297.
Ziser S.W. 1978. Seasonal variations in water chemistry and
diversity of the phytophilic macroinvertebrates of three swamp
communities in southeastern Louisiana. Southwestern Naturalist
23 (4) :545-562.
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APPENDIX A. Site Maps and Sampling Points
82
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Maps provided by site operators of the Orlando and Lakeland
sites are included in this appendix. The treatment cells" are
numbered for reference. The following features are designated on
each map: vegetation transect locations (Orlando site only),
invertebrate sample locations, and whole effluent toxicity water-
sampling points. Some of the invertebrate samples were collected
at a single spot in the wetland, designated by an X on the maps.
When invertebrate densities were low, however, several net samples
had to be collected to obtain 1/2 hour of collection time.
Therefore, Xs connected by a dotted line represent places where
samples consisting of several nettings were taken along a shoreline
or the edge of vegetation from a single habitat type.
The key below describes the symbols and features found on maps
in this appendix:
Dikes
® Influent sample collection point
-©- Effluent sample collection point
. . Vegetation transects
X or X X Invertebrate sample locations
1 Rookery Islands
83
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ARTIFICIAL
LAKELAND SITE
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APPENDIX B. Site Contacts and Local Experts Consulted
86
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ORLANDO
Site Contact:
Alan R. Oyler, P.E.
Assistant Bureau Chief - Bureau of Wastewater
Environmental Services Department - City of Orlando
5100 L.B. McLeod Road
Orlando, FL 32811
Botanists consulted:
Dr. Bill Dunn
CH2M Hill
7201 NW llth Place
P.O. Box 1647
Gainesville, FL 32602-1647
Mike Mahler
Polk County Environmental Services
Bendurrac Road
Winter Haven, FL
Seth Blitch and Jim Burney
Post, Buckley, Schuh, and Jernigan, Inc.
Winter Park Plaza
1560 Orange Ave., Suite 700
Winter Park, FL 32789
Aerial Photography Company;
Kucera International, Inc.
Dick Connors/Larry Towles
3550 Drain Field Road
Lakeland, FL 33811
Bird Surveyors;
Dr. Peter C. Frederick and Steven M. McGehee
Department of Wildlife and Range Sciences
118 Newins-Ziegler Hall
University of Florida
Gainesville, FL 32611
Water Analysis Laboratories;
Bureau of Wastewater Laboratory, City of Orlando, FL
Contact: Alan Oyler -Orlando site contact
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LAKELAND
Site Contact:
Dave Hill
Wastewater Operations
City of Lakeland Department of•Public Works
1825 Glendale Street
Lakeland, FL 33803
Botanist consulted:
Dr. Bill Dunn
CH2M Hill
7201 NW llth Place
P.O. Box 1647
Gainesville, FL 32602
Aerial Photography Company:
Kucera International, Inc.
Dick Connors/Larry Towles
3550 Drain Field Road
Lakeland, FL 33811
Bird Surveyors;.
Dr. Peter C. Frederick and Steven M. McGehee
Department of Wildlife and Range Sciences
118 Newins-Ziegler Hall
University of Florida
Gainesville, FL 32611
Water Analysis Laboratory;
City of Lakeland Wastewater Treatment Laboratory,.Lakeland, FL
Contact: Dave Hill, site manager
88
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APPENDIX C.
Invertebrate Biologists and Identification Keys
Used
89
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-J
• I
Biologists:
Nan Allen; Ann Hershey
221 Life Sciences Bldg. - Biology office
10 University Drive
University of Minnesota-Duluth
Duluth, MN 55812
Invertebrate taxonomic keys used:
Borror, D.J., C.A. Triplehorn, and N.F. Johnson. 1989. An
Introduction to the Study of Insects. Sixth Edition. Sanders
College Publishing. Philadelphia, PA.
Klemm, D.J. 1982. Leeches (AnnelidarHirudinea) of North
America. EPA-600/3-82/025. Environmental Protection Agency
Environmental Monitoring and Support Lab. Office of Research and
Development, Cincinnati, OH.
Merritt, R.W. and K.W. Cummins. 1984. An Introduction to the
Aquatic Insects of North America. Second Edition. Kendall Hunt
Publishing Co., Dubuque, IA.
Pennak, R.W. 1978. Freshwater Invertebrates of the United
States. Second Edition. John Wiley and Sons, Inc., New York, NY.
Pennak, R.W. 1989. Freshwater Invertebrates of the United
States. Third Edition. John Wiley and Sons, Inc., New York, NY.
Usinger, R.L. (Ed.). 1968. Aquatic Insects of California, with
North American Genera and California Species. University of
California Press, Berkeley, CA.
Ward, H.B. and G.C. Whipple (Eds.). 1959. Fresh Water Biology.
Second Edition. John Wiley and Sons, Inc., New York, NY.
Wiederholm, T. (Ed.). 1983. Chironomidae of the Holarctic'
Region. Part 1 Larvae. Entomologica Scandinavica Supplement No.
19. Borgstroms Tyckeri AB, Motala.
90
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I*
APPENDIX D. Water Chemistry of Replicate Samples Used for
Whole Effluent Toxicity Tests.
91
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J
ft)
Sample
Orlando site
Influent
Effluent
Control
Influent
Effluent
Control
Ceriodaphnia dubia chronic test*
Mean
pH
7.25
7.25
8.03
8.12
8.16
8.17
pH
Range
Mean
Temp
Mean
DO*
(ma/L)
Initial Chemistries
7.17-7.35
7.14-7.35
7.87-8.11
25.9
25.7
26.3
Final Chemistries
8.05-8.18
8.12-8.22
8.10-8.22
25.2
25.4
25.5
8.7
9.0
7.9
8.1
8.2
8.1
Mean
Conductiv.
(umhos/cm)
485
401
128
Lakeland site
Influent
Effluent
Control
7.22
7.67
8.35
Initial Chemistries
7.20-7.26
7.63-7.70
8.31-8.37
25.5
25.5
26.2
Final Chemistries
9.3
9.1
8.6
1178
668
108
Influent
Effluent
Control
7.84 7.80-7.89 26.0
8.11 8.05-8.18 26.0
8.20 8.20-8,21 26.4
8.3
8.3
8.4
"means based on 10 replicates
*DO * dissolved oxygen
--SB not measured
92
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&
•-t
T*
(Appendix D, continued)
Fathead minnow acute testsb - Orlando site
Sample
Influent
Effluent
Control
Influent
Effluent
Control
Mean
DH
7.20
7.20
7.99
7.86
7.96
8.01
PH
Range
Initial
7.17-7.24
7.14-7.27
7.87-8.11
Final
--
Mean
Temp
Chemistries
25.8
25.5
26.1
Chemistries
25.0
25.2
25.1
Mean
DO
(mg/L)
8.5
8.8
7.9
7.6
7.8
7.9
Mean
Conduct iv.
(umhos/cm)
- . t
487
399
131
-- •
Note: a fathead minnow test was not conducted on the Lakeland sample..
bmeans based on two replicates
*DO = dissolved oxygen
-- = not measured
93
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APPENDIX E. Bird Species Lists Based on Ground Counts and
Inventories.
94
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Bird species observed during informal ground counts and field sampling
at the Lakeland site, 1991-1992. *=birds observed on 5 informal bird
counts from November 1991 to June 1991 and during field sampling in
1991; + = birds observed only during field sampling.
* Pied-billed Grebe
American White Pelican
* Double-crested Cormorant
* Anhinga
American Bittern
* Least Bittern
* Great Blue Heron
* Great Egret
* Snowy Egret
* Little Blue Heron
+ Tri-colored Heron
* Cattle Egret
* Green-backed Heron
* Black-crowned Night Heron
* White Ibis
Glossy Ibis
Roseate Spoonbill
Wood Stork
Hooded Merganser
* Wood Duck
Mottled Duck
Mallard
Pintail
Blue-winged Teal
Black Vulture
* Turkey Vulture
* Osprey
Bald Eagle
Northern Harrier
Red-shouldered Hawk
American Kestrel
* Northern Bobwhite
* Common Moorhen
American Coot '
Killdeer
Black-necked Stilt
Greater Yellowlegs
Lesser Yellowlegs
Spotted Sandpiper
Ring-billed Gull
Common Tern
+ Gull-billed Tern
* Mourning Dove
Common Ground Dove
* Belted Kingfisher
Eastern Phoebe
+ Eastern Kingbird
Tree Swallow
+ Barn Swallow
Blue Jay
American Crow
Tufted Titmouse
American Robin
* Northern Mockingbird
* Loggerhead Shrike
+ White-eyed Vireo
Yellow-throated Warbler
* Northern Cardinal
+ Rufous-sided Towhee
* Red-winged Blackbird
Eastern Meadowlark
* Boat-tailed Crackle
Common Crackle
95
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Bird species recorded throughout the period of site operation (1987-
1991) at the Orlando site (list provided by Post, Buckley, Schuh, and
Jernigan, Inc., Winter Park, FL). * = bird species seen or heard
during field sampling in 1991.
*Pied-bilied Grebe
American White Pelican
* Double-crested Cormorant
*Anhinga
American Bittern
* Least Bittern
*Great Blue Heron
* Great Egret
*Snowy Egret
* Little Blue Heron
*Tricolored Heron
* Cattle Egret
* Green-backed Heron
Black-crowned Night-Heron
Yellow-crowned Night-Heron
* White Ibis
Glossy Ibis
Roseate Spoonbill
Wood Stork
Fulvous Whistling-Duck
Wood Duck
Green-winged Teal
* Mottled Duck
Mallard
Northern Pintail
Blue-winged Teal
Northern Shoveler
Gadwall
American Wigeon
Canvasback
Ring-necked Duck
Lesser Scaup
Common Goldeneye
Hooded Merganser
Ruddy Duck
A Black Vulture
* Turkey Vulture
Osprey
American Swallow-tailed Kite
* Snail Kite
Bald Eagle
Northern Harrier
Sharp-shinned Hawk
* Red-shouldered Hawk
Short-tailed Hawk
American Kestrel
Merlin
Peregrine Falcon
Wild Turkey
Northern Bobwhite
King Rail
Sora
Purple Gallinule
*Common Moorhen
* American Coot
*Limpkin
Sandhill Crane
Black-bellied Plover
KiUdeer
American Oystercatcher
Black-necked Stilt
Greater Yellowlegs
Lesser Yellowlegis
Solitary Sandpiper
Spotted Sandpipeir
Least Sandpiper
Dunlin
Long-billed Dowi tcher
Common Snipe
Ring-billed Gull
Caspian Tern
Forster'sTem
*Mouming Dove
Common Ground-Dove
Common Barn-Owl
Eastern Screech-Owl
*BarredOwl
Common Nighthsiwk
Chuck-wuTs-widow
Chimney Swift
*Belted Kingfisher
Red-headed Woodpecker
*Red-beUied Woodpecker
Yellow-bellied &ipsucker
Downy Woodpecker
Northern Flicker
*Pileated Woodpecker
Eastern Phoebe
Great Crested Flycatcher
Eastern Kingbird
Purple Martin
Tree Swallow
*Bam Swallow
Blue Jay •
American Crow
* Fish Crow
*Tufted Titmouse
Carolina Wren
House Wren
Sedge Wren
Marsh Wren
Ruby-crowned Kinglet
Blue-gray Gnatcatcher
Hermit Thrush
American Robin
Gray Catbird
Northern Mockingbird
Brown Thrasher
Water Pipit
Cedar Waxwing
* Loggerhead Shrike
European Starling
White-eyed Vireo
Solitary Vireo
Orange-crowned Warbler
Northern Parula
YeUow-nimped Warbler
Yellow-throated Warbler
Pine Warbler
Prairie Warbler
Palm Warbler
Black-and-white Warbler
American Redstart
Prothonotary Warbler
Ovenbird
*Common Yellowthroat
^Northern Cardinal
Indigo Bunting
Rufous-sided Towhee
Savannah Sparrow
Henslow's Sparrow
Song Sparrow
Swamp Sparrow
Bobolink
*Red-winged Blackbird
Eastern Meadowlark
*Boat-tailed GrackJe
Common Crackle
Brown-headed Cowbird
American Goldfinch
House Sparrow
96
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