Home Archived October 29, 2018

South Florida Information Access (SOFIA)

projects > role of marsh-mangrove interface habitats as aquatic refuges for wetland fishes and other aquatic animals > scope of work

Project Scope of Work

Project Scope of Work 2003

Role of Marsh-Mangrove Interface Habitats as Aquatic Refuges for Wetland Fishes & Other Aquatic Animals

1. Introduction/Background.

The Water Resources Development Act (WRDA) of 2000 authorized the Comprehensive Everglades Restoration Plan (CERP) as a framework for modifications and operational changes to the Central and Southern Florida Project needed to restore the south Florida ecosystem. Provisions within WRDA 2000 provide for specific authorization for an adaptive assessment and monitoring program. A Monitoring and Assessment Plan (MAP) has been developed as the primary tool to assess the system-wide performance of the CERP by the REstoration, COordination and VERification (RECOVER) program. The MAP presents the monitoring and supporting enhancement of scientific information and technology needed to measure the responses of the South Florida ecosystem.

The MAP also presents the system-wide performance measures representative of the natural and human systems found in South Florida that will be evaluated to help determine the success of CERP. These system-wide performance measures address the responses of the South Florida ecosystem that the CERP is explicitly designed to improve, correct, or otherwise directly affect. A separate Performance Measure Documentation Report being prepared by RECOVER provides the scientific, technical, and legal basis for the performance measures.

Generally, the scope of work (SOW) described below is intended to support four broad objectives of the MAP:

a. Establish pre-CERP reference state including variability for each of the performance measures

b. Determine the status and trends in the performance measures

c. Detect unexpected responses of the ecosystem to changes in stressors resulting from CERP activities

d. Support scientific investigations designed to increase ecosystem understanding, cause-and-effect, and interpret unanticipated results

The SOW is intended to support the Greater Everglades (GE) Wetlands module of the MAP and is directly linked to the monitoring or supporting research component identified in that module as number This SOW includes the objectives of the work order effort, a general description of the scope citing the methodologies to be used by USGS to perform the data collection, a detailed breakdown of the tasks to be performed and associated deliverables and timeframes, planning, coordination, data review, report preparation and submittal, equipment purchases, rental and ownership and Project Management.

Wetland Fishes and Other Aquatic Animals are essential to the successful functioning of wetlands in southern Florida through their roles as prey and predators. Any changes that reduce the population sizes, community composition, or availability of aquatic animals will affect all facets of the ecology of these wetlands. Therefore, the multi-agency groups responsible for guiding CERP have recognized fishes as a key indicator group by which to measure restoration success. Studies of small-bodied fishes in freshwater marshes at many Everglades sites have been funded by the National Park Service (NPS), South Florida Water Management District (SFWMD), and the U S Army Corps of Engineers (Corps) since the 1970s (Loftus and Eklund 1994, Trexler et al. 2000, and Trexler et al. 2001). The data analyses allow evaluation of seasonal and long-term dynamics, shifts in relative abundance and size-structure, and produce correlations of fish abundance to water depth, hydroperiod, and plant community structure. This long-term fish database in the Everglades has been used to document the effects of water management in southern Florida (Loftus et al. 1992, Loftus and Eklund 1994, Trexler and Loftus 2001, and Trexler et al. 2001) and was used in the Across Trophic Level System Simulation (ATLSS) fish-simulation model (DeAngelis et al. 1997) developed to evaluate future restoration scenarios and estimate historical fish communities. However, much data in the model regarding the seasonal use of shallow and deep-water habitats had to be estimated because no data were available.

Aquatic animals in seasonal wetlands are subjected to widely variable environmental conditions during the annual hydrological cycle. They face mortality from desiccation, starvation, stress-related disease, hypoxia, predation, and in the case of introduced tropical species, cold temperatures. Which habitats in the ecosystem provide protection from these conditions, how do those habitats function in physical and biological terms, and how will they change as a result of restoration actions? A major need is the understanding of how the physical aspects of refuges affect their use by the biota. Few studies have examined the assemblages of fishes in natural deep-water habitats in south Florida wetlands, and those mainly in alligator pond (Kushlan 1974, Nelson and Loftus 1996). Relatively little is known about fish dynamics and use of stream channels at the marsh/mangrove interface of southwest Florida, despite its former importance for wading bird nesting. Small-scale studies have provided inventory data from some channels (Tabb and Manning 1961, Tabb et al. 1962, McPherson, 1970, Odum 1971, Loftus and Kushlan 1987) that indicated mixing of estuarine fishes and freshwater fishes in the channels. However those studies were mainly short-term and qualitative. A goal of CERP is to reestablish conditions in that region that will support renewed wading bird nesting there. Because wading birds depend on fishes as prey, some scientists hypothesize that the abundance or availability of fishes has been altered by management to the detriment of the birds.

2. Objectives.

a. Develop quantitative sampling programs and methods from studies of stream-channel fish communities through a literature search

b. Test and develop methods for measuring catch per unit effort (CPUE) and density in oligohaline habitats.

c. Document the composition of native and introduced fishes and their habitat use.

d. Measure important correlative physical measurements such as relative water depths in channels and wetlands, salinity, temperature.

e. Test methods of analyzing elemental ratios in bones to determine extent of fish movements from interface refuges into sloughs and peripheral wetlands using a combination of caged and wild fish

3. Scope of Work.

a. Location and Design of Wetland Fishes Sites: Some interface habitat sampling issues must be addressed during the first year of the work order associated with this SOW. These will include the study locations, design, and the appropriate monitoring and sampling methods. The location of the study sites will also allow dovetailing with other studies conducted by Florida International University (FIU) and Audubon Society of Florida (ASF) that are testing methods to monitor fish assemblages in the shallow wetlands at the mangrove interface. By focusing this SOW on fish assemblages in the creeks, and co-locating our sampling sites and times with other funded efforts, the work order associated with this SOW should be able to track fish movements from wetlands to creeks during the wet, transitional, and dry seasons. All of the previous sampling methods provide CPUE data, which give a relative measurement of the fish assemblage that can be compared among the channels and among the time periods. If the channels are shallow enough, a 1-m2 throw trap may be used to obtain density data for the small fishes. This possibility should be tested in the first year. In the process, the analyses will result in improvements to the ATLSS fish models for freshwater and estuarine fishes, giving us more confidence in the tools used to restore this internationally recognized ecosystem. Quantitative, baseline information collected by repeatable methods before and after CERP project implementation is needed to assess the effects of restoration actions.

b. Interface Habitat Monitoring: This SOW will develop and test methods to monitor seasonal changes in fish community composition in headwater creeks in two southwest Florida drainages: Rookery Branch in Shark Slough and Lostman's River. Neither Florida drainages have the fish communities in the oligohaline reaches received enough attention to delineate the fauna and its seasonal and annual patterns. Shark River Slough has been affected by water management to a greater extent than has the Lostman's drainage farther west, and it will also likely receive more effects from CERP projects. A comparison of these two drainages will provide baseline ecological data on the fishes before CERP projects are implemented.

c. Interface Habitat Sampling and Locations: The initial work plan will include sampling of three tributary channels within each of the Florida drainages mention above. Boat and helicopter access will be used to decide on the location of sampling sites with the at Shark and Lostman's rivers. The SFWMD has agreed to provide limited helicopter support for access to data collection sites at no charge to USGS under this SOW. There are a number of research and monitoring studies ongoing in both drainages, such as the National Park Service and the FIU Long Term Ecological Research (LTER) programs, from which data will be used to supplement data collected for this SOW. Methods similar to those used to sample deep-water habitats in the south Florida wetlands will be used or adapted including the use of a boat-mounted electrofisher to collect catch data at high and low water times (Nelson and Loftus 1996, Trexler et al. 2001). Channels and pools in the interface region probably served as an important dry-season refuge for fishes when the wetlands dry out, but they also served to concentrate those fishes for both avian and piscine predators. There are state-of-the-art electrofishers rated to shock in oligohaline waters, but their use will require testing in the first year. If salinities become too high for electrofishers to operate, other methods will have to be employed at that time of year. Sites that are as far upstream as can be reached by motorboat should be selected for this SOW. The habitat that will be sampled is the upstream portion of the channel opening directly to the marsh from which fishes have unimpeded access to the channel. In sites downstream on these rivers, the mangroves form a solid barrier that interrupts connections between marsh and channel. Data and rules for fish behavior will be incorporated into the ATLSS fish model to improve its performance for the marsh/mangrove region, particularly relating to the timing of fish concentrations in the channels and their movements away from that refuge in the wet season.

d. Physical Measurements: Physical measurements will be collected throughout the year, including water level/relative depths, temperature, and salinity. Correlative hydrological data will be gathered as discontinuous data from local staff gauges, and as continuous daily data from nearby recording stations. Those data are necessary to characterize seasonal conditions in the river channels, and to address questions relating to the suitability of habitats for the fishes and their movement patterns. This SOW will provide data to describe the role of water-level and salinity patterns in mediating habitat use by the fishes (Odum et al. 1982). The intent is to build an understanding of water level and salinity effects on the fish assemblages in this region. Studies conducted by the FIU and ASF and funded by other sources will share a variety of physical measurements collected during the year. These will include water level/relative depths, temperature, and salinity. Correlative hydrological data will be gathered as discontinuous data from local staff gauges, and as continuous daily data from nearby recording stations. Those data will help determine whether and how often those deep-water habitats become too saline in some years to support the full suite of freshwater species, or too cold for survival of introduced tropical species. Water-depth data in the wetlands and channels will allow description of depth thresholds when fishes move into or from the channels to wetlands.

e. Permits: Collecting permits from Everglades and Big Cypress National Parks will be required to complete the work associated with this SOW.

4. Work Breakdown Structure.

a. Introduction. The results of the work performed under this statement of work will be used to develop the cumulative finds of the AAT System Status Annual Reports. These annual reports will be used by the AAT to develop a RECOVER Technical Report at five-year intervals, as pursuant to the regulations [Section 385.31 (b)(4)]. This Technical Report presents an assessment of whether the goals and purposes of the CERP are being achieved. The Report will also include an assessment of whether the Interim Goals and Interim Targets are being achieved or likely to be achieved and evaluating whether corrective actions should be considered based on scientific findings of system-wide or regional ecological needs. The Principal Investigator(s) (PI) will be required to work with the AAT Modules Chair to assist in the development of the AAT System Status Annual Report and asked to include their participation as a task in this work breakdown structure. Additionally, the following reporting guidance is offered by AAT to the principal investigator(s):

1) Evaluate Ability to Detect Change - PI Level
a) Describe the results of the power analysis for the sampling design.
b) Determine the minimum detectable difference of the power analysis, and its associated confidence and uncertainty.
c) Describe changes in the MAP sampling design and its implications for the power analysis and the minimum detectable difference.

2) Establish Reference Condition - PI Level
a) Describe the non-MAP data sources, if any, used in the assessment. If non-MAP data were used, did the data meet the guidance criteria? If the non-MAP data were used and did not meet the guidance criteria, provide a rationale to justify the inclusion of the data.
b) Describe how representative the data are in space and time.
c) Describe the approaches used to address measuring variability.
d) Enter the data into the CERPP-Zone and update Module Group

3) Measure Change from Reference Condition - PI Level
a) Describe the methods used to estimate the direction and magnitude of change in performance measures from the reference state both annually and back-cast for multiple years.
b) Compare current status of the PM with its desired trend or target.
c) Evaluate consistency of monitoring results with MAP hypotheses.
d) Determine if there are indications of unanticipated events and describe how they are affecting the desired outcome.

4) Annual Integration of Performance Measures (PM) To Evaluate Module Hypotheses -Module Group Level
a) Annually integrate multiple PMs to provide an assessment of module level hypotheses.
b) Describe the direction and magnitude of change in the integrated performance measures, and determine if the changes are consistent with expected responses described in the CERP hypotheses.
c) If the trends do not correspond to expected responses provide scientific explanation.
d) Evaluate progress toward achieving module-level Interim Goals and Interim Targets.

5) System-Wide Performance Evaluation - AAT Level
a) Synthesize findings across-modules and across years to provide a holistic description of the status of the system.
b) Evaluate the results in relationship to; supporting system level hypotheses and achieving system-wide Interim Goals and Interim Targets.
c) Summarize those system-wide changes that are consistent with goals and hypotheses and those that are not.
d) Provide a scientific discussion of why the goals and hypotheses are not being achieved.

b. Task Descriptions.

Task 1 - Sampling of Seasonal Fish Assemblages at the Marsh-Mangrove Interface in Southwestern Everglades National Park.

(1) Deliverables - Work will include a minimum of three years of field data collection, and time in the final year to analyze and write the final report and manuscript. Invoices for work will be submitted with each report. All annual, final and summary reports will include an assessment and/or analysis of the data or activity as it relates to the ecological premise and CERP hypothesis described in the MAP. The assessments will include descriptions of the native and exotic fish assemblages, tests for correlations among fish species and environmental conditions, and trends of CPUE to show seasonal use of the channel habitats by fishes.

(2) Timeframe - Sampling will be carried out three times each year for three years: a) wet season (October-November) periods; b) transitional (February) periods; and c) dry season (April-May) periods.

(3) Task 1 is comprised of several elements and milestones.

Task 1 Elements FY04 FY05 FY06 FY07
Initial Planning Meeting x      
Work plan Writing x      
Fish Sample Design x      
Site Location x      
Methods Testing x      
Field Collections   x x x
Lab Processing   x x x
Cage Study   x x  
Otolith Analysis   x x  
Annual Reports   x x  
Coordination w ATLSS   x x  
Final Report   x x  

Note - In the second and third years of the work order associated with this SOW, testing will be conducted to determine whether the channel refuges provide a source of colonists for long-distance dispersal into the sloughs and peripheral wetlands. In other ecosystems, researchers have successfully used the ratio of strontium to calcium in fish bones to identify its origins as freshwater or estuarine. By using a combination of caging captive-reared fishes and placing them in each environment to uptake that environment's signature, and by sampling wild fishes from a number of locations, it should be possible to determine whether this area is a source of fishes for distant sites. Using a combination of caged and wild fish, methods for the analysis of elemental ratios in fish bones will be tested to determine extent of fish movements from interface refuges into sloughs and peripheral wetlands.

c. Literature Search, Planning, and Data Analysis. The first step is a thorough search of the literature for sampling programs and methods used to quantify stream-channel fish communities. This initial step is followed by the identification of sampling sites where methods for measuring catch per unit effort (CPUE) and density in oligohaline habitats will be tested. Once methods and locations are identified, the study will document the composition of native and introduced fishes and their habitat use. At the same time, important correlative measurements will be taken that include physical parameters such as relative water depths in channels and wetlands, salinity, temperature. The intent is to build an understanding of water level and salinity effects on the fish assemblages in this region. Collected field measurements provide important answers that contribute directly to restoration decision tools and planning. Data and rules for fish behavior will be incorporated into the ATLSS fish model to improve its performance for the marsh/mangrove region, particularly relating to the timing of fish concentrations in the channels and their movements away from that refuge in the wet season.

d. Data Collection. Large-bodied species will be field-processed and returned alive, except for voucher and life history samples. Small-bodied species will be collected for processing in the laboratory. Fishes will be handled using guidelines for humane treatment, including the use of anesthetics for reducing capture trauma or for euthanasia. Small-bodied fishes moving into or out of the wetlands to the channels will be sampled utilizing methods similar to those described in Loftus et al. (2001). Sampling methods that provide a 24-hour catch measure and a description of the direction of fish movement will be utilized. Access to a fully functional laboratory will be required to process field samples and perform analyses.

e. Equipment and Logistics. The only electrofisher on the market able to accomplish the sampling in low salinity waters is the Smith-Root #9 Boat Electrofisher. USGS owns a motorboat with this unit which will be available to this SOW. In addition, water-monitoring data loggers will be needed to monitor physical conditions in the channels and marshes. All sampling will be done in remote areas of Everglades National Park. To reach the remote areas, a motorboat equipped with a powerful electrofisher is necessary. The boat must be towed to Flamingo by vehicle to be launched, and fieldwork will probably require overnight camping in the backcountry. Use of the SFWMD helicopter on several occasions during the transition and rewetting periods may be necessary to collect additional samples when fishes are most likely to be moving

f. Reports. The first report in FY04 will be a letter report defining the preliminary work to date and the invoiced funds will allow USGS to contract for resources to perform the work not executed by in-house personnel. Because the SOW is a multi-year effort, annual reports are due at the end of each year and a final report is due approximately 90 days after the completion of the WO associated with this SOW.

(1) Deliverables - Letter report, annual, final reports, and publications.

(2) Timeframe -

Letter report - within 30 days of Notice to Proceed (NTP)
Annual Reports - within 60 days of the completion of each year's work
Final Report - within 90 days of WO completion.
Publications - any resulting from WO will be provided to RECOVER.

5. Project Management.

a. SOW Change Control. Changes in the SOW must be requested of the project manager in writing, with supporting justification. Any requested changes in the SOW will require, on part of USGS, submission of an updated project work plan with supporting detail, updated scheduling and budget information. No changes in the SOW will occur without permission from the project manager. Any delays or changes in the work order (WO) scheduling and budget will require consultation with the Adaptive Assessment Team (AAT) of RECOVER. If the original SOW requires any approved changes, USGS must include documentation of these scope changes in the "lessons learned" section of the final project report.

In addition, for multi-year work orders in which the results of each year's work can or will modify what happens in the subsequent years of the work order, the annual report can or will provide a summary of work completed to date and proposed revisions to the future schedule of tasks/deliverables.

b. Data Management. Submission of all data is required for work order closeout. Data formatting, analysis, and delivery will be required to meet all CERP data management standards that can be obtained from the CERP Data Management Program Managers. Any data derived from the SOW will be provided to the AAT at predetermined intervals. All data and results derived from this SOW must be made publicly available or available to the AAT at the end of the work order.

c. Quality Control and Assurance. The work plan will include a quality assurance plan in order to determine which quality control and quality assurance procedures are appropriate for each project (e.g., QASR, FDEP standards). Methods used for each project should be selected based upon the following criteria (if appropriate): cost-benefit analysis, flowchart diagram of the system process, and determination of the best statistical experimental design. The burden of proof of compliance with standardized quality control and assurance procedures is the responsibility of the contractor. In the case where there are not standardized methods for quality control and assurance, the contractor must prove that the suggested methodologies are rigorous. Citation of peer-reviewed and published methods may be used to support this documentation.

d. Status Reporting. Regular progress reports will be made to the project manager as deemed by the task list. Reports will be written (verbal reports are not acceptable). Informal reports regarding status of permits needed for the work order or timely progress of field work or those that describe the completion of specific task elements may be transmitted via email or fax. Reports that include any type of data analysis, datasets, and formal quarterly or interim reports will also be sent via electronic mail; however, signed hard copies with data attached in appropriate format must be mailed to the project manager.

e. Lessons Learned. The causes of variances in the SOW, project scheduling and budgeting, the reasoning behind any corrective action, as well as any other lessons learned will be clearly documented in the final project report. These lessons learned will become part of the historical database for this project and other RECOVER projects.


Literature Cited:

DeAngelis, D. L., W. F. Loftus, J. C. Trexler, and R. E. Ulanowicz. 1997. Modeling fish dynamics and effects of stress in a hydrologically pulsed ecosystem. Journal of Aquatic Ecosystem Stress and Recovery 6: 1-13.

Kushlan, J. A. 1974. Effects of a natural fish kill on the water quality, plankton, and fish population of a pond in the Big Cypress Swamp, Florida. Trans. Am. Fish. Soc. 103:235-243.

Loftus, W. F. and A. M. Eklund. 1994. Long-term dynamics of an Everglades fish community. Chapter 19, pp. 461-483 IN S. Davis and J.C. Ogden (Editors). Everglades: the System and its Restoration. St. Lucie Press, Delray Beach, Florida.

Loftus, W. F. and J. A. Kushlan. 1987. Freshwater fishes of southern Florida. Bulletin of the Florida State Museum, Biological Sciences 31: 147-344.

Loftus, W. F., M. C. Bruno, K. J. Cunningham, S. A. Perry, and J. C. Trexler. 2001. The ecological role of karst wetlands of southern Florida in relation to system restoration. Proceedings First annual meeting, U.S. Geological Survey Karst Interest Group, St. Petersburg, Florida, February 13-16, 2001. Water-Resources Investigations Report 01-4011.

Lorenz, J. J. 1997. The effects of hydrology on resident fishes of the Everglades mangrove zone. Final report to Everglades National Park from National Audubon Society, Tavernier, FL.

McPherson, B. F. 1970. Hydrobiological characteristics of Shark River estuary, Everglades National Park, Florida. Open File Report No. 71002, U. S. Geological Survey, Tallahassee, FL.

Nelson, C. M. and W. F. Loftus. 1996. Effects of high-water conditions on fish communities in Everglades alligator ponds, Pages 89-101 IN T. V. Armentano (Editor). Proceedings of the 1996 Conference: Ecological Assessment of the 1994-1995 High Water Conditions in the southern Everglades. Florida International University, Miami, FL, 22-23 August 1996.

Odum, W. E. 1971. Pathways of energy flow in a south Florida estuary. Sea Grant Tech. Bull. No. 7. Univ. of Miami Sea Grant Program, Miami, FL.

Odum, W. E., C. C. McIvor and T. J. Smith, III. 1982. The ecology of the mangroves of south Florida: A community profile. U. S. Fish and Wildlife Service, Office of Biological Services, FWS/OBS-81/24. 144 pp. Washington D.C.

Tabb, D. C. and R. B. Manning. 1961. A checklist of the flora and fauna of northern Florida Bay and adjacent brackish waters of the Florida mainland collected during the period July 1957 through September 1960. Bull. Mar. Sci. Gulf and Carib. 11:552-649.

Tabb, D. C., D. L. Dubrow, and R. B. Manning. 1962. The ecology of northern Florida Bay and adjacent estuaries. Tech. Series No. 39. Fla. State Board of Conserv. Tallahassee, FL.

Trexler, J. C. and W. F. Loftus. 2001. Analysis of relationships of Everglades fish with hydrology using long-term databases from Everglades National Park. Final report to Everglades National Park under FIU Cooperative Agreement CA5280-8-9003. 101 pages.

Trexler, J. C., W. F. Loftus, F. Jordan, J. J. Lorenz, J. H. Chick, and R. M. Kobza. 2000. Empirical assessment of fish introductions in southern Florida: an evaluation of contrasting views. Biological Invasions 2: 265-277.

Trexler, J. C., W. F. Loftus, F. Jordan, J. H. Chick, K. L. Kandl, T. C. McElroy, and O. L. Bass, Jr. 2001. Ecological scale and its implications for freshwater fishes in the Florida Everglades. Pages 153-181 IN J. W. Porter and K. G. Porter (Editors). The Everglades, Florida Bay, and coral reefs of the Florida Keys: an ecosystem sourcebook. CRC Press, Boca Raton, Florida.

| Disclaimer | Privacy Statement | Accessibility |

U.S. Department of the Interior, U.S. Geological Survey
This page is: http://sofia.usgs.gov/projects/scopesofwork03/role_marsh_mang.html
Comments and suggestions? Contact: Heather Henkel - Webmaster
Last updated: 04 September, 2013 @ 02:08 PM(KP)