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Project Scope of Work

Project Scope of Work 2003

American Alligator Distribution, Size, and Hole Occupancy and American Crocodile Juvenile Growth & Survival

map showing alligator spotlight survey routes and capture survey locations for south Florida
Figure 1. Alligator spotlight survey routes and capture survey locations for south Florida. [larger image]
1. Introduction. 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 of 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 statement 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 research component identified as MAP Activity Numbers 3.1.3.15 and 3.1.3.16. 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 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.

2. Background. At present, a network of alligator night surveys has been established and surveys have been conducted since 2001 to assess alligator distribution and body condition throughout the Greater Everglades ecosystem. This network was designed to satisfy the requirements for monitoring changes in alligator populations over relatively short time periods as a result of restoration. Critical Ecosystems Studies Initiative (CESI) funded the development of the network and procedures. This funding will continue through 2004 but does not include the further development of procedures as outline in Alligators Task 1 of this SOW.

Early studies (late 1970's) on the status and ecology of the American crocodile (Crocodylus acutus) in Florida were summarized by Mazzotti and Cherkiss (2003) and funded by others; U.S. National Park Service (NPS), Florida Game and Fresh Water Fish Commission (now Florida Fish and Wildlife Commission (FWC), and the Florida Power and Light Company (FPL). The purposes of these early studies were to learn how to manage and monitor crocodiles in Florida. During the mid 1980's into the 1990's crocodile studies were funded to also evaluate the experimental Modified Water Delivery program for Everglades National Park (ENP), while FPL continued to monitor crocodiles at the Turkey Point Power Plant site and FWC continued to monitored crocodiles on North Key Largo. More recently, crocodile projects with the dual purposes of monitoring impacts of CERP projects and evaluating the status of crocodiles for endangered species recovery have been funded by the Critical Ecosystems Studies Initiative (CESI) and the U.S. Fish and Wildlife Service (FWS). A kickoff meeting including more than 30 biologists, managers, and administrators from federal, state, and county agencies and several universities was held in Homestead in November 2002 to develop a list of critical projects for restoration and evaluation of crocodilian populations, performance measures required by CERP to evaluate ecosystem response to CERP projects, and the monitoring required to assess restoration success. Mazzotti and Cherkiss (2003), as part of a CESI funded project, made specific recommendations for recovery of crocodiles in Florida including restoration success criteria and monitoring needs. This SOW for the MAP Greater Everglades Modules 3.1.3.15 and 3.1.3.16 is based on that kickoff meeting and summary report of Mazzotti and Cherkiss. A review of the baseline/historical dataset also has been conducted through a project funded by the CESI of the U.S. National Park Service (USNPS) and this SOW was developed based on the review of the baseline/historical dataset.

The American crocodile thrives in healthy estuarine environments and, in particular, is dependent on freshwater deliveries (Mazzotti 1999). In this regard, crocodiles can be used to evaluate restoration alternatives and to set success criteria for Florida and Biscayne bays. Water management practices have changed natural patterns of freshwater inflow to Florida and Biscayne bays. Less freshwater in Florida Bay suggests that crocodiles not only grow more slowly, but also have to disperse farther. Both factors negatively impact survival and the suitability of shoreline and island nest sites. In northeastern Florida Bay, the combination of saline water and long distance dispersal appears to limit hatchling growth and survival. In the lab, crocodiles grow best when the salinity is less than 50% seawater (18 ppt) and they lose mass when exposed to salinity greater than 40 ppt unless freshwater is provided periodically (Mazzotti 1983). In the field, lower growth and survival rates have been associated with higher salinities (Mazzotti and Cherkiss 2003). The working hypothesis for this relationship is that crocodiles that grow faster are also in better condition (relatively fatter) than crocodiles that grow more slowly.

The relative distribution and abundance of crocodiles also reflects these salinity patterns. Within an area, most crocodiles occur at the lower end of the available salinity gradient (Mazzotti 1983, Brandt et al. 1995, Mazzotti and Cherkiss 2003). Most sightings of crocodiles are in water of less than 20 ppt, and most sightings of crocodiles in more saline water are females attending nest sites or juveniles presumably avoiding adults of foraging. It is believed that the restriction of freshwater flow into an estuary will decrease the relative density of crocodiles and that restoring or enhancing freshwater flow would increase relative density. The increase in crocodiles and crocodile nests on the freshwater side of Buttonwood Canal after it was plugged provides anecdotal support for this hypothesis. The MAP identified growth and survival of crocodiles as performance measures for CERP.

3. Objectives. Note - The four objectives listed below have been separated into Alligators and Crocodiles.

a. Alligators.

1) Design and develop a monitoring program for relative distribution, size (condition), nesting and hole occupancy rates of the American alligator in response to CERP projects as specified in the MAP. The monitoring program and procedures developed will provide the baseline for future comparisons and an effective means for evaluating restoration success for the American alligator in the Greater Everglades ecosystem.

2) Monitor changes in alligator populations due to restoration over short (body condition), medium (distribution, hole occupancy) and long (nesting) temporal and spatial scales.

b. Crocodiles.

1) Design and develop a monitoring program for growth and survival of crocodiles in areas that will be affected by CERP projects.

2) Surveys for crocodiles will be conducted as expressed in the MAP following methods described by Mazzotti and Cherkiss (2003). Monitoring surveys will be separated into subtasks based on geographic area. In all areas, crocodile surveys and monitoring will include nesting effort and success and will focus on growth and survival of juvenile crocodiles.

4. Scope of Work - Alligators. The Alligator portion of this SOW will be divided into three main tasks: 1) distribution and condition of alligators, 2) nesting ecology of alligators, 3) alligator hole mapping and occupancy.

a. Distribution and Condition of Alligators. Relative condition of alligators will be determined by conducting a condition factor analysis (Leslie 1997, Zweig 2003).

b. Monitoring of Nesting Alligators. As outlined below, monitoring of nesting alligators with Standard Reconnaissance Flights (SRF) at Everglades National Park (ENP) (Dalrymple 2001) and with airboat surveys by the U.S. Fish and Wildlife Service and the University of Florida (UF) at Arthur R. Marshall Loxahatchee National Wildlife Refuge (Loxahatchee NWR) (Brandt and Mazzotti 2000) has been conducted. Everglades National Park will continue the airboat surveys into newly restored habitats in the ENP as outlined in this SOW. The proposed work outlined in this SOW extends nesting surveys and will begin the collection of information concerning clutch characteristics at Loxahatchee NWR.

c. Alligator Hole Mapping and Occupancy. To date, alligator holes have been mapped in Water Conservation Area (WCA) 2, WCA3, and Loxahatchee NWR and several funding agencies have contributed to these studies. No previous work has been conducted nor funding proposed for alligator hole occupancy as outlined in this SOW.

d. Alligator Surveys. To date, survey routes of estuarine rivers, freshwater canals and marshes extending from the mangrove fringe of ENP north through Loxahatchee NWR have been established (Figure 1). Random transects will be surveyed in cells where landscape patterns and wetland fish populations are monitored. Surveys along these routes will be performed by skiff, canoe, johnboat, airboat, and truck. Alligator locations will be recorded using GPS equipment and field maps. Spotlight surveys in each area will be conducted twice in both spring and fall at least 14 days apart in order to achieve independent counts (Woodward and Moore 1990). For this SOW night-light counts will be supplemented by aerial and ground surveys in areas spatially or temporally inaccessible by boats such as coastal creeks and rocky glades.

e. Alligator Study Areas. The study area for alligator monitoring includes those areas contained within the Greater Everglades ecosystem (see Figure 1). Alligator Study areas expected to be influenced most by CERP, such as the rocky glades, will be surveyed for alligator hole occupancy initially.

5. Work Breakdown Structure - Alligators & Crocodiles.

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.

6. Work Breakdown Structure - Alligators.

a. Task Descriptions.

1) Task 1 - Alligator Distribution and Size (Condition). Distribution and size will be determined using night-light and semi-annual capture surveys. Correlations between alligator submergence and several environmental variables such as air and water temperatures, time, moon phase, season, and habitat will be investigated using transmitters with an integrated Global Positioning System (GPS).

a) Distribution of Alligators

1) Nightlight counts
2) Supplemental aerial and ground surveys
3) Correction factors for alligator surveys:
Distance sampling
Wariness
Proportion of time at surface

b) Alligator Size (Condition) - Sizes of alligators will be estimated in quarter meter increments whenever possible.

Approach and Methods - Night-light (or spot-light) and capture surveys will be used to determine distribution and condition of alligators. Night-light counts are an accepted means of monitoring alligator populations as an index to population size, but many assumptions need to be tested to make the surveys reliable. To develop reliable relative population estimates using night-lighting counts, estimates of detection probability will be determined (Anderson 2003). Currently, variation in detection probabilities of alligators due to habitat, wariness, and animal behavior is not estimated. These sources of variation will be investigated using different sampling methods. These estimates of variation can then be used as correction factors for our night-light counts. If estimates of detection probability can be obtained, one can better detect and evaluate trends in populations of alligators over time as required by CERP. Capture surveys will be used in conjunction with night-light surveys to provide data for a body condition factor analysis (Leslie 1997, Zweig 2003).

Deliverable and Timeframe - Quarterly progress reports will begin 3 months after NTP. Annual summary reports will be due 1 year after NTP. A final synthesis report will be prepared at the end of this task and will include but not be limited to; monitoring plan procedures and analysis, trend analyses for the alligator sizes, physical parameter measurements, and detailed route information. Peer-reviewed publications, theses, and dissertations will be provided upon completion and request.

2) Task 2 - Alligator Nesting Ecology: Differences in primary nesting habitat of alligators at ENP (open marsh area) and Loxahatchee NWR (tree islands) will require different survey techniques. Both survey techniques (SRF & airboat) have been used successfully in previous studies (Brandt and Mazzotti 2000, Dalrymple 2001).

a) System Reconnaissance Flights (SRF's) will be used at ENP:
Extend SRF's into mangrove zone and rocky glades

b) Surveys in Loxahatchee NWR will use airboats.

Approach and Methods - The nesting ecology task has been separated into subtasks based on location because differences in primary nesting habitat of alligators at ENP (open marsh area) and Loxahatchee NWR (tree islands) require different survey techniques. Standard Reconnaissance Flights have been used successfully at ENP (Dalrymple 2001) and airboat surveys have proven successful at Loxahatchee NWR (Brandt and Mazzotti 2000); thus, they will be used at these two study sites, respectively. After initial flights are completed, a series of nests will be selected for ground visits to examine eggs. A minimum of 20% of the estimated total nests will be sampled every year. Nests will be visited at least once during the incubation period. During the initial visit, eggs will be counted and their viability determined (Dalrymple 2001). During follow up visits, the fate of eggs will be determined.

ENP study area, SRF's will fly east west transects at 2-km intervals from a helicopter at a height of 40 m and ground speed of 50 knots. Since the greatest change in nesting is expected in freshwater-mangrove and rocky glades areas an evaluation of extending or modifying transects in those areas will be necessary before beginning the SRF survey. Observers on each side of the helicopter will count all nests in a belt 250 m wide for a total width of 500 m. The helicopter will be flown over each nest and its position will be recorded using a GPS. Areas surveyed will include Shark River Slough, Northeast Shark River Slough, mangrove estuary, portions of Big Cypress National Preserve, Rocky Glades, East Slough, and the Taylor Slough/C-111 basin.

For the Loxahatchee NWR study area, ten plots of 1.6 x 1.6 km have been selected using the 3.2 x 3.2 km grid cells of the SFWMD Water Management Model and the indicator regions developed for the Central and Southern Florida Project Comprehensive Review Study (Corps and SFWMD 1999) and the MAP. Three plots have been selected as areas to sample within each of the indicator regions. Nests will be located from the ground using airboats and all plots will be searched for alligator nests via north to south meandering transects (approximately 200 m width). A GPS will be used to record the path of each survey route. Tree islands and alligator holes will be circled to locate trails and nests. Trails going into tree islands will be searched on foot. The amount of time spent searching by boat and by foot will be recorded. Location (GPS coordinate), physical description of the area, and nest, as well as presence of a female, will be noted when a nest is located. Nests will be flagged and revisited in August or September to determine their fate. The presence and location of old nests also will be recorded. In addition to initial nest searches, limited "double sampling" will be conducted to determine the proportion of nests found by each observer and to estimate the total number of nests constructed in the area.

Deliverable and Timeframe - Quarterly progress reports will begin 3 months after NTP. Annual summary reports will be due 1 year after NTP. A final synthesis report will be prepared at the end of this task and will include but not be limited to; monitoring plan procedures and analysis, trend analyses for nesting ecology, physical parameter measures, and detailed route information. Peer-reviewed publications, theses, and dissertations will be provided upon completion and request.

3) Task 3 - Alligator Hole Mapping and Occupancy: Alligator holes will be located and mapped using a combination of aerial photography and GPS technology. Occupancy rates of alligator holes will be determined by a combination of helicopter and airboat surveys.

a) Approach and Methods - Alligator holes will be located and mapped using a combination of aerial photography and GPS technology. This is a proven, cost effective method for mapping alligator holes at high resolution over a large area and has been used to map alligator holes in WCA's 2 and 3 (Campbell and Mazzotti 2001). A geographic information system (GIS) will be used to analyze photographic imagery and to manage GPS data. Occupancy rates of alligator holes will be determined by a combination of helicopter and airboat surveys. A series of transects similar to those described in the SRF will be used. Initially, those areas expected to be influenced most by CERP such as the rocky glades will be surveyed for alligator hole occupancy.

b) Deliverable and Timeframe - Quarterly progress reports will begin 3 months after NTP. Annual summary reports will be due 1 year after NTP. A final synthesis report will be prepared at the end of this task and will include but not be limited to; monitoring plan procedures and analysis, trend analyses for hole occupancy, physical parameter measurements, detailed route information, and the geo-referenced alligator hole maps. Peer-reviewed publications, theses, and dissertations will be provided upon completion.

6. Coordination, Data Review, and Planning. This portion of the SOW continues and builds upon a well-defined and reviewed dataset, and it involves partners that have worked together on similar studies for over 10 years. A detailed work plan will be developed which will include how all collected data will be reviewed. A joint alligator/crocodile kickoff meeting will be held shortly after NTP is given to ensure data collection, data analysis and review, and data management are standardized, and logistical issues are addressed.

7. Data Collection. Semi-annual capture surveys will be performed using similar vehicles and locations shown in Figure 1 to determine the condition of alligator populations. A minimum of 15 alligators greater than 75 cm total length will be captured by hand, noose, or tongs in each area twice yearly. Total length (TL), snout-vent length (SVL), head length (HL), tail girth (TG), and weight will be measured, sex determined, and any abnormalities/deformities noted. At Loxahatchee NWR, clipping the tail scutes will mark alligators; elsewhere, GFC/FWC web tags will be used to identify recaptured individuals. Location, habitat characteristics, and environmental data including habitat type, air and water temperature, salinity, water depth, muck depth, wind and wave action, and spot water levels will be recorded at set locations along routes. See also under Tasks 1, 2, and 3 Approaches and Methods.

8. Technology. New technology is available to locate animals using transmitters with an integrated GPS. Transmitters can be affixed with a collar/backpack. However, this technology has not been attempted with alligators. Low-cost technology also exists to integrate a conductivity data logger with the transmitter to determine the proportion of time spent above and below water. This study will examine correlations between alligator submergence and several habitat variables in an effort to better determine trends relative to location of animals and environmental factors.

9. Permits. All of the necessary endangered species and access permits for executing this SOW have been or are in the process of being issued and are available upon request.

10. Reports. See above under Tasks 1, 2, and 3, Deliverable and Timeframe.

11. Equipment Purchase, Rental, and Ownership. Equipment purchases for the Alligator portion of this SOW includes: two radio-telemetry receivers and approximately twenty-five GPS radio-transmitters. Since this SOW is long term (3 years) in nature and possibly funded by RECOVER AAT in future years, it is considered more cost effective to purchase the receivers and transmitters rather than to rent or lease these items. Ownership of all capital expenses purchases under this SOW with Government funds will become the property of the government at the conclusion of the work order.

12. Helicopter Support. The SFWMD has agreed to provide limited helicopter support for access to remote alligator data collection sites at no charge to the Government. Anticipated helicopter support needed is estimated at 100 hours per year for alligator data collection.

13. Scope of Work - Crocodiles. The Crocodile portion of this SOW will consist of one task: The American Crocodile juvenile growth and survival.

a. Crocodile Nest Areas. This SOW proposes monitoring juvenile crocodile growth and survival in the Cape Sable-Flamingo and West Coast River areas, as these locations are likely to be affected by CERP projects. There were relatively few crocodiles and nests in the Cape Sable-Flamingo area and fewer crocodiles and no documented nests in the West Coast River system (Broad River to Chatham River) area in the ENP. In the past two years, there has been a dramatic increase in crocodiles and nests in the Cape Sable Area and sightings of crocodiles along the west coast in Rogers River, Gopher Creek, and Highlands Beach.

b. Crocodile Study Areas. The study area for the juvenile crocodile monitoring includes the entire mangrove shoreline between the Coral Gables Waterway and Chatham River, including North Key Largo and other near shore keys. When the MAP was first being developed, two locations, southern Biscayne Bay and northeastern-central Florida Bay were identified as likely to be affected areas by future CERP projects.

14. Work Breakdown Structure - Crocodiles.

a. Task Descriptions.

1) Task 4 - Estimate juvenile growth and survival rates of crocodiles in areas affect by CERP projects. To help in the execution of Task 4 all work will be conducted in two distinct phases:

a) Phase 1 - This phase consists of two subtasks to determine the appropriate quantitative methods for performing the spatial and temporal analyses required by MAP and to apply that analysis to developing a detail work plan that combines existing methods of data collection with the appropriate experimental design and statistical analysis. Since all of the previous studies on the status and ecology of the American crocodile (Crocodylus acutus) in Florida have been summarized (Mazzotti and Cherkiss (2003)) that effort is unnecessary.

Subtask 1 - Analyze existing data to determine the appropriate analytical methods.

1) Approach and Methods - Analyze existing databases on crocodiles (Mazzotti and Cherkiss 2003) to determine appropriate statistical methods for making the spatial temporal comparisons required by the MAP. Models of crocodilian growth (Brandt 1991) and vertebrate survival (White and Burnham 1999) will be evaluated for their usefulness in evaluating data collected. Mazzotti and Cherkiss used empirical estimates of growth (absolute growth) and survival (direct enumeration) to compare growth and survival among the nesting colonies in South Florida. These measures may not be adequate to make the spatial and temporal comparisons required of MAP.

2) Deliverable - Quarterly progress reports will begin 3 months after NTP. Annual/Final report will be due 1 year after NTP.

3) Timeframe - One year from NTP

Subtask 2 - Use the results of Subtask 1 above to refine the sampling procedures in the succeeding subtasks.

1) Approach and Methods - Develop a detailed work plan that will utilize the results of subtask 1. Refine appropriate analytical methods for crocodile monitoring and meet the requirements of the MAP performance measure.

2) Deliverable - Quarterly progress reports will begin 3 months after NTP. Annual summary reports will be due 1 year after NTP. A final synthesis report will be prepared at the end of this task and will include but not be limited to; the work plan, data collection procedures, refined analytical methods, and other pertinent information.

3) Timeframe - Three years from NTP

b) Phase 2 - This phase consists of a series of recurring subtasks to acquire the data needed to make the analyses and assessments. The subtasks are separated by location, with the same activities conducted within each area.

Subtask 3 - Juvenile Crocodile growth and survival monitoring in Biscayne Bay through Barnes Sound.

1) Approach and Methods - Population surveys and monitoring in Biscayne Bay through Barnes Sound will include nesting effort and success, and will focus on growth and survival of juvenile crocodiles. Population surveys and monitoring of crocodiles will be conducted following the methods described by Mazzotti and Cherkiss (2003). Growth and survival of juvenile crocodiles will be assessed by quarterly surveys and capture efforts (Mazzotti 1999, Mazzotti and Cherkiss 2003).

2) Deliverable - Quarterly progress reports will begin 3 months after NTP. Annual summary reports will be due 1 year after NTP. A final synthesis report will be prepared at the end of this task and will include but not be limited to; the monitoring plan procedures and analysis, trend analyses for the monitored crocodile populations, physical parameters measured, and other pertinent information. Peer-reviewed publications, theses, and dissertations will be provided upon completion and request.

3) Timeframe - Three years from NTP

Subtask 4 - Juvenile crocodile growth and survival monitoring in northeastern and central Florida Bay, ENP

1) Approach and Methods - Population surveys and monitoring in northeastern and central Florida Bay, ENP will include nesting effort and success, and will focus on growth and survival rates of juvenile crocodiles. Population surveys and monitoring of crocodiles will be conducted following the methods described by Mazzotti and Cherkiss (2003). Growth and survival of juvenile crocodiles will be assessed by quarterly surveys and capture efforts (Mazzotti 1999, Mazzotti and Cherkiss 2003).

2) Deliverable - Quarterly progress reports will begin 3 months after NTP. Annual summary reports will be due 1 year after NTP. A final synthesis report will be prepared at the end of this task and will include but not be limited to; the monitoring plan procedures and analysis, trend analyses for the monitored crocodile populations, physical parameters measured, and other pertinent information.

3) Timeframe - Three years from NTP.

Subtask 5 - Juvenile crocodile growth and survival monitoring in the Cape Sable/Flamingo Area, ENP.

1) Approach and Methods - Population surveys and monitoring in the Cape Sable/Flamingo Area, ENP will include nesting effort and success, and will focus on growth and survival of juvenile crocodiles. Population surveys and monitoring of crocodiles will be conducted following the methods described by Mazzotti and Cherkiss (2003). Growth and survival of juvenile crocodiles will be assessed by quarterly surveys and capture efforts (Mazzotti 1999, Mazzotti and Cherkiss 2003).

2) Deliverable - Quarterly progress reports will begin 3 months after NTP. Annual summary reports will be due 1 year after NTP. A final synthesis report will be prepared at the end of this task and will include but not be limited to; the monitoring plan procedures and analysis, trend analyses for the monitored crocodile populations, physical parameters measured, and other pertinent information.

3) Timeframe - Three years from NTP.

Subtask 6 - Juvenile crocodile growth and survival monitoring in the west coast river system (Broad River to Chatham River), ENP.

1) Approach and Methods - Population surveys and monitoring in the west coast river system (Broad River to Chatham River), ENP will include nesting effort and success, and will focus on growth and survival of juvenile crocodiles. Population surveys and monitoring of crocodiles will be conducted following the methods described by Mazzotti and Cherkiss (2003). Growth and survival of juvenile crocodiles will be assessed by quarterly surveys and capture efforts (Mazzotti 1999, Mazzotti and Cherkiss 2003).

2) Deliverable - Quarterly progress reports will begin 3 months after NTP. Annual summary reports will be due 1 year after NTP. A final synthesis report will be prepared at the end of this task and will include but not be limited to; the monitoring plan procedures and analysis, trend analyses for the monitored crocodile populations, physical parameters measured, and other pertinent information.

3) Timeframe - Three years from NTP.

15. Coordination, Data Review, and Planning. This portion of the SOW continues and builds upon a well defined and reviewed dataset, and involves partners that have worked together on similar studies for over 10 years. A detailed work plan will be developed which will includes how all collected data will be reviewed. A joint alligator/crocodile kickoff meeting will be held shortly after NTP is given to ensure data collection, data analysis and review, and data management are standardized, and logistical issues are addressed.

16. Data Collection. Determining crocodile nesting effort and success is necessary for maximizing the ability to mark hatchling crocodiles and will be determined by searching known and potential nesting habitat during April and May (effort) and July and August (success) for activity (tail drags, digging or scraping) or the presence of eggs or hatchlings. Hatchlings will be captured, measured, marked, and released. See also Subtasks 1 through 6 under Task 4, Approach and Methods.

17. Technology. New technology is available to locate animals using transmitters with an integrated GPS. Transmitters can be affixed with a collar/backpack. However, this technology has not been attempted with alligators. Low-cost technology also exists to integrate a conductivity data logger with the transmitter to determine the proportion of time spent above and below water. This study will examine correlations between alligator submergence and several habitat variables in an effort to better determine trends relative to location of animals and environmental factors.

18. Permits. All of the necessary endangered species and access permits for executing this SOW have been or are in the process of being issued and are available upon request.

19. Reports. See above under Subtasks 1 through 6 under Task 4, Deliverable and Timeframe.

20. Equipment Purchase, Rental, and Ownership. No trucks, airboats, boats, computers, and other capital expenses are included in the in the crocodile fee proposal for this SOW.

21. Helicopter Support. No helicopter support is needed for crocodile data collection in this SOW.

22. Project Management.

a. Statement of Work 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 the contracting entity, 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 project 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 SOW report.

In addition, for a multi-year SOW 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 project will be provided to the AAT at predetermined intervals. All data and results derived from this project must be made publicly available or available to the AAT at the end of the project. Peer-reviewed publications, theses, and dissertations will be provided upon completion and at the request of RECOVER AAT.

c. Quality Control and Assurance. The work plan(s) will include a quality assurance plan in order to determine which quality control and quality assurance procedures are appropriate for each study (e.g., QASR, FDEP standards). Methods used for each work order 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 project or timely progress of field work or those that describe the completion of specific tasks 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 statement of work, project scheduling and budgeting, the reasoning behind any corrective action, as well as any other lessons learned will be 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:

Anderson, D.R. 2003. Index values rarely constitute reliable information. Wildlife Society Bulletin. 31:288-291.

Brandt, L.A. and F.J. Mazzotti. 2000. Nesting of alligators at the Arthur R. Marshall National Wildlife Refuge. Florida Field Naturalist. 28:122-126.

Campbell, M.R. and F.J. Mazzotti. 2001. Mapping Everglades Alligator Holes Using Color Infrared Aerial Photography. Florida Scientist. 64:148-158.

Dalrymple, G.H. 2001. American alligator nesting and reproductive success in Everglades National Park: An analysis of the systematic reconnaissance flight (SRF) data from 1985-1998. Everglades Research Group, Inc. Final Report.

Leslie, A.J. 1997. The ecology and physiology of the Nile crocodile, Crocodylus niloticus, in Lake St. Lucia, Kwazula/Natal, South Africa. PhD Dissertation. Drexel University, Philadelphia, Pennsylvania.

U.S. Army Corps of Engineers and South Florida Water Management District [USACE and SFWMD]. 1999. Central and Southern Florida Project Comprehensive Review Study Final Integrated Feasibility Report and Programmatic Environmental Impact Statement. Army Corps of Engineers, Jacksonville District, Jacksonville, Florida and South Florida Water Management District, West Palm Beach, Florida.

Woodward, A.R., and C.T. Moore. 1990. Statewide alligator surveys. Final Report. Bureau of Wildlife Research, Florida Game and Fresh Water Fish Commission, Tallahassee, Florida.

Zweig, C.L. 2003. Body Condition Factor Analysis for the American Alligator (Alligator mississippiensis). M.S. University of Florida, Gainesville, Florida.



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