Project Work Plan

Study Title: Predicting Effects of Hydrologic Restoration on Manatees along the Southwest Coast of Florida
Study Start Date: 2000 Study End Date: 2005
Web Sites: http://cars.er.usgs.gov/Manatees/manatees.html
Location (Subregions, Counties, Park or Refuge): Total System - Southern Golden Gate Estates, Ten Thousand Islands NWR, Collier County; Everglades National Park, Monroe County.
Funding Source: USGS Greater Everglades Priority Ecosystems Science (GE PES)
Other Complementary Funding Source(s): Complementary study "Characterizing winter refugia for manatees in the northwestern Everglades region" funded through USGS/CARS
Principal Investigator(s): James Reid
Study Personnel: James Reid, Brad Stith, Susan Butler, Daniel Slone
Supporting Organizations: U.S. Fish and Wildlife Service - Ten Thousand Islands National Wildlife Refuge, the National Park Service - Everglades National Park, Big Cypress National Preserve, Florida Fish and Wildlife Conservation Commission - Florida Marine Research Institute, Rookery Bay National Estuarine Research Reserve, Mote Marine Laboratory, Marine Mammal Commission, and Cincinnati Zoo
Associated / Linked Studies: Linkages to other projects/databases include TIME model, ATLSS model, and the associated PBS projects: "Impacts of Hydrological Restoration on Three Estuarine Communities of the Southwest Florida Coast and on Associated Fauna" (Carol McIvor) (http://sofia.usgs.gov/projects/impacts_est/); "Southwest Florida Coastal and Wetland Systems Monitoring Project" (E. Patino) (http://sofia.usgs.gov/projects/sys_monitor/) Additional information on "Predicting Effects of Hydrologic Restoration on Manatees along the Southwest Coast of Florida" is available on the Sofia website: http://sofia.usgs.gov/projects/manatees/

Overview & Objective(s): Determine relative abundance, distribution, movements, and habitat use of manatees associated with coastal waters and rivers from Marco Island through Whitewater Bay. Identify resources critical to manatees in the region, including distribution and abundance of submerged aquatic vegetation and locations of freshwater drinking sites. Develop an individual-based ATLSS model to predict manatee response to changes in hydrology achieved specifically by the Southern Golden Gate Estates (SGGE) project and more broadly by the Comprehensive Everglades Restoration Plan. Additional information on population trend, distribution, and habitat use, coupled with models of hydrology, bathymetry, aquatic vegetation, and salinity, will allow development of a population-level model capable of predicting their response to future changes. This SGGE modeling effort will provide invaluable information as a small-scale test case for understanding and predicting how restoration efforts in the Everglades will affect manatees.

Specific Relevance to Major Unanswered Questions and Information Needs Identified: (Page numbers below refer to DOI Science Plan.)

This study supports two of the projects listed in the DOI science plan, including: Southern Golden Gate Estates Hydrologic Restoration, and Landscape-Scale Modeling.

The study supports the Southern Golden Gate Estates Hydrologic Restoration project (SGGE; p. 51) by 1) modeling predicted changes in hydrology and ecology in the Ten Thousand Islands NWR (p. 59), and 2) providing baseline data and monitoring of effects on a federally listed species, the West Indian manatee, within the Ten Thousand Islands NWR (p. 59-60).

The study supports the Landscape-Scale Modeling (LSM; p. 80-81) by 1) providing an individual-based demographic model of a threatened species, the West Indian manatee (p. 80), and 2) by providing landscape-scale monitoring and assessment for MAP (p. 81, 90).

This study supports the CERP Monitoring and Assessment Plan, Part 1, Southern Estuaries Module, Section 3.2.4.10: Manatee Abundance and Distribution Relative to Freshwater Input (pp. 3-98 - 3-100).

This study also supports the Planning Aid Report, Multi-species Conservation under Comprehensive Everglades Restoration Plan (CERP), Project 30, Southern Golden Gate Estates Hydrologic Restoration Project (pp. 252-254, 262-264).

Each manatee project task addresses a number of USGS project tasks related to hydrology, habitats and species, ecological indicators, and threatened and endangered species. Because the manatee is a federally listed species, our work supports a variety of needs identified by the DOI for listed species.

Status: On track for completion in FY05.

Recent Products:

Metadata reviewed, revised, and posted to SOFIA

Presentations at the 15th Biennial Conference on the Biology of Marine Mammalogy:

Brad Stith, Jim Reid, and Susan Butler, 2003, Modeling manatee response to restoration in the Ten Thousand Islands and Everglades National Park. Oral presentation at the 15th Biennial Conference on the Biology of Marine Mammals, 15-19 December 2003, Greensboro, North Carolina.

James P. Reid, Bradley M. Stith, and Susan M. Butler, 2003, Florida manatees in the western Everglades: Implications for restoration assessment. Oral presentation at the 15th Biennial Conference on the Biology of Marine Mammals, 15-19 December 2003, Greensboro, North Carolina.

Susan M. Butler, James P. Reid, and Bradley M. Stith, 2003, Detailed movements and habitat use patterns of radio tagged manatees in the western Everglades. Poster presentation at the 15th Biennial Conference on the Biology of Marine Mammals, 15-19 December 2003, Greensboro, North Carolina. Available at http://cars.er.usgs.gov/posters/index.html#manatee

Planned Products:

Two presentations submitted to the First National Conference on Ecosystem Restoration

Open File Report - November 2004

Telemetry database available for posting - Spring 2005

Model output for ATLSS viewer - September 2005

Scientific manuscripts for peer review

WORK PLAN

Title of Task 1: Radio Tracking Manatees to Assess the Impact of Hydrologic Changes in Southwest Florida
Task Funding: USGS Greater Everglades Priority Ecosystems Science (GE PES)
Task Leaders: James P. Reid
Phone: 352-372-2571 ext. 15
FAX: 352-374-8080
Task Status (proposed or active): Active
Task priority: Medium
Time Frame for Task 1: first quarter FY05
Task Personnel: Jim Reid, Susan Butler, Brad Stith, and Skip Snow (ENP)

Task Summary and Objectives:

The radio-tracking task provides data critical for documenting the pre-restoration use of habitat by manatees within the region affected by the SGGE restoration. These data are essential for validating parameters in the individual-based model described in task 3. Satellite-based Argos transmitters and Global Positioning System (GPS) tags have been used to remotely track movements of 36 manatees; radio tracking efforts are ongoing. Most manatees were captured and radio-tagged during the winter months at Port of the Islands, Faka Union canal, Collier County. Preliminary analysis of movement patterns suggest that manatees in this region rely on existing freshwater sources, usually traveling between offshore seagrass beds and these inshore freshwater sites every 3-5 days. Individual movements are linked to a network of seagrass beds, which is revealed by manatee locations during GPS tag deployments. Seven of the manatees tracked in this study also traveled to areas more than 100 km north of the Ten Thousand Islands. Most remained within the study area, however, providing the first detailed movement data collected across seasons from wild manatees in the region.

Work to be undertaken during the proposal year and a description of the methods and procedures:

We have relied on two types of technologies to acquire geographic locations from tagged manatees. Most tagged manatees are fitted with satellite-based Argos transmitters, which provide approximately four location fixes per 24-hour period, and have a serviceable battery life of six months. Four newly developed Argos-linked GPS tags have been acquired and deployed in FY03. This tag relays GPS locations as sensor data through the Argos satellite link, enabling detailed tracking data to be acquired remotely. The GPS tag provides locations which are much more accurate than the Argos data (approx. 30 m vs. >150 m) every 15-30 minutes, but the battery life expectancy is much shorter (8 weeks vs. 6 months). In combination, the Argos data provides region-wide, long-term coverage suitable for revealing general patterns of habitat use, while the GPS data shows fine details of travel pathways and time spent in specific areas. Location data are formatted in SAS for error checking, analyses, and display in ArcView. Databases are correlated with temperature, salinity, and tidal data collected throughout the region.

Further descriptions of methods and procedures can be seen at the following web site:

http://www.fcsc.usgs.gov/posters/Manatee/Radio_Tracking_Manatees/radio_tracking_manatees.html

http://www.fcsc.usgs.gov/posters/Manatee/GPS_Tag_for_Sirenians/gps_tag_for_sirenians.html

Field efforts planned for FY05 are minimal. Tagged manatees will be tracked through the end of the 2004 wet season. These individuals will then be utilized in the second year of a companion study on the winter-use patterns of manatees in the TTI region. Tagged manatee movement and environmental data collected between 2000 and 2004 from the study area will be error-checked and formatted for analysis. This will enable further development of the model efforts detailed in Task 2.

Remote and field-based tracking has enabled documentation of manatee use patterns associated with near shore habitats. These findings are relevant for determination of submerged aquatic vegetation planned for the PBS project "Impacts of Hydrological Restoration on Three Estuarine Communities of the Southwest Florida Coast and on Associated Fauna" (Carol McIvor) http://sofia.usgs.gov/projects/impacts_est/. Collaboration with this project is planned to establish baseline data on the patterns of distribution and abundance of submerged aquatic vegetation in the TTI and ENP.

Distribution and movement data on manatees, combined with water quality data obtained from monitoring stations, will provide a basis for comparative studies in other areas within the region. Sharing of tracking and model data, such as manatee high use areas and travel patterns, are planned with TTI, ENP, and other agencies to address resource management needs.

Specific Task Product(s):

Open File Report - November 2004

Presentations submitted to the First National Conference on Ecosystem Restoration - December 2004

Telemetry database available for posting - Spring 2005

Scientific manuscript for peer review

Title of Task 2: Development of an Individual-based ATLSS Model for Manatees to Evaluate the Impact of Hydrologic Change in Estuaries of Southwestern Florida
Task Funding: USGS Greater Everglades Priority Ecosystems Science (GE PES)
Task Leaders: Brad Stith
Phone: 352-372-2571 ext. 24
FAX: 352-374-8080
Task Status (proposed or active):
Task priority: High
Time Frame for Task 2: FY05
Task Personnel: Brad Stith, Daniel Slone, Jim Reid, Susan Butler

Task Summary and Objectives:

We are developing a spatially-explicit, individual-based ATLSS model for manatees to better understand how changes in hydrology associated with restoration of SGGE and the Everglades may affect the distribution and abundance of manatees. Telemetry data and aerial surveys have demonstrated that manatees make regular use of many of the tidal rivers and streams within the study area, primarily as a source of drinking water and as thermal refugia during cold weather. To date, all 26 manatees we have analyzed show a similar pattern of regular movement between near shore seagrass beds and sources of freshwater up various rivers, creeks, and canals. Our task is to use the telemetry data and water quality information to explain the movement patterns of manatees, and to incorporate these insights into the individual-based manatee model to properly simulate these movements and the response of manatees to alterations in hydrology.

Work to be undertaken during the proposal year and a description of the methods and procedures:

Work to be undertaken includes four major tasks: 1) finalize the analysis of manatee telemetry data obtained from Task 2 to support the development and parameterization of the individual-based model, 2) develop empirically-based surrogates for hydrology model output simulating the relationship between salinity and freshwater inflow for major rivers, 3) finalize and validate the individual-based manatee model, 4) devise and conduct a set of simulation runs to evaluate different restoration scenarios.

The telemetry data analysis task involves using GIS techniques to analyze the telemetry data and characterize manatee behavior, including habitat use, movement patterns, time budget, and home range size. We are using the telemetry data to delineate a comprehensive network of sites used by manatees which will provide the landscape used in all simulations. The fine-scale GPS data is being used to develop detailed travel corridors between offshore and inshore areas, as well as movement speeds for incorporation into the model. The coarse-scale Argos data is being used in a robust, multi-state mark-recapture model to analyze the movement of manatees between different habitat zones (e.g. riverine and offshore). This analysis provides transition probabilities as input into the individual-based model in a Monte Carlo Markov Chain framework to model the transition of manatees between different habitat zones, and to provide a measure of individual heterogeneity in transition probabilities. We will complete the analysis of manatee home ranges using a fixed kernal approach with least square cross validation smoothing to identify overall home range, and core areas of utilization. Patterns of individual heterogeneity in home range size and location will be incorporated into the model. We are using a simple reinforcement model (Rescorla-Wagner) to model shifts in manatee home ranges in response to changes in availability of freshwater. A sensitivity analysis will be conducted to evaluate the parameters with the strongest influence on the model. We will devise a set of simple restoration scenarios that vary the influx of freshwater within the network of river systems used by manatees. The "status quo" scenario will be used to output data from the model to compare to the telemetry data (task 1) and to several years of aerial survey data (completed for a previous task). The response of simulated manatees to several different scenarios representing alternative restoration scenarios will be compared and evaluated.

Because no hydrology model is available for the estuarine or marine portions of this study area, we will analyze data from monitoring stations within the study area to develop empirical relationships between freshwater discharge and salinity gradients at varying distances from point of discharge. We will vary these empirical relationships to simulate output from a hydrology model under alternative restoration scenarios. Water quality data will be obtained from several sources, including the USGS PBS project "Southwest Florida Coastal and Wetland Systems Monitoring Project" (E. Patino) (http://sofia.usgs.gov/projects/sys_monitor/).

Further descriptions of methods and procedures can be seen at the following web sites:

www.fcsc.usgs.gov/posters/Manatee/Modeling_Manatee_Movements/modeling_manatee_movements.html

Water quality data will be obtained from several sources, including the USGS PBS project "Southwest Florida Coastal and Wetland Systems Monitoring Project" (E. Patino) (http://sofia.usgs.gov/projects/sys_monitor/)

Specific Task Product(s):

Open File Report - November 2004.

Presentation submitted to the First National Conference on Ecosystem Restoration - December 2004.

Model output for ATLSS viewer - September 2005

Scientific manuscript for peer review.