A. GENERAL INFORMATION:

Project Title: Predicting Effects of Hydrologic Restoration on Manatees along the Southwest Coast of Florida
Project Start Date: 2000 Project End Date: 2005
Project Funding: USGS Place-Based Studies Initiative, USGS Center for Aquatic Resource Studies
Principal Investigator: James P. Reid
Email address: Jim_Reid@usgs.gov
Phone: 352-372-2571 ext. 15 Fax: 352-374-8080
Mail address:
Florida Caribbean Science Center
US Geological Survey
412 NE 16th Ave., Room 250
Gainesville, FL 32601

Other Investigator(s): Bradley M. Stith
Email address: Bradley_Stith@usgs.gov
Phone: 352-372-2571 ext. 24 Fax: 352-374-8080
Mail address:
Florida Caribbean Science Center
US Geological Survey
412 NE 16th Ave., Room 250
Gainesville, FL 32601

Other Investigator(s): Susan M. Butler
Email address: Susan_Butler@usgs.gov
Phone: 352-372-2571 ext. 22 Fax: 352-374-8080
Mail address:
Florida Caribbean Science Center
US Geological Survey
412 NE 16th Ave., Room 250
Gainesville, FL 32601

Project Summary:

This project focuses on West Indian manatee (Trichechus manatus latirostris) distribution, habitat use and movement patterns to address questions important to understanding the ecology of several communities in southwest Florida used by manatees, including offshore seagrass beds, estuarine bays, tidal creeks, and rivers. A large proportion of the southwest Florida manatee population occurs throughout the Everglades National Park (ENP) and north into the Ten Thousand Islands (TTI). Our on-going research in this area has shown that manatees make frequent movements up tidal creeks to obtain freshwater for drinking and to find thermal refugia during cold weather. Alteration of the freshwater and estuarine ecosystems associated with restoration of the Everglades and Southern Golden Gate Estates is likely to affect this manatee population. In addition, because manatees feed primarily on submerged aquatic vegetation (SAV) in estuarine and near-offshore areas, they are excellent barometers of the health of a range of communities. By providing baseline data on these communities, this research will be important to future monitoring of the effects of the South Florida hydrological restoration efforts. In so doing, this research addresses the most basic major issue i.e., "How will hydrological changes in quantity and quality of freshwater impact downstream aquatic habitats?" We hypothesize that manatee distribution, relative abundance, habitat use, and movement patterns will change because of altered water management regimes and resulting changes in near shore salinity. Telemetry data from tagged manatees (Task 1) provide a valuable means of documenting the response of manatees to natural and human-induced fluctuations in freshwater inflow. This information, combined with water quality data obtained from monitoring stations, will be incorporated into the manatee ATLSS model (Task 2), which will be used to better understand and predict manatee response to different restoration scenarios.

Project Objectives and Strategy:

The major objectives of the study are to determine relative abundance, distribution, movements, and habitat use of manatees associated with coastal waters and rivers in the western everglades, and to develop an individual-based ATLSS model to predict manatee response to changes in hydrology achieved by the Southern Golden Gate Estates (SGGE) project specifically, and more broadly by the Comprehensive Everglades Restoration Plan. Work has primarily focused on the TTI/SGGE restoration area, with some data also collected from tagged manatees using the southwest portion of ENP. Data for this project is collected via: satellite telemetry and tracking of individuals using a specially designed Global Positioning System (GPS) tag. Data will be used in developing the predictive manatee model (Task 2), which will integrate with the TIME model.

Potential Impacts and Major Products:

The manatee model developed as part of this research will be a valuable component of the ongoing ATLSS modeling effort to judge and compare restoration scenarios. Model output will be useful to the U. S. Army Corps of Engineers, the South Florida Water Management District, U.S. Fish and Wildlife Service, Ten Thousand Islands National Wildlife Refuge, Everglades National Park, and other agencies involved in implementation of the Comprehensive Everglades Restoration Plan. This project will also fill a significant void in our knowledge of manatee ecology, as there is very little existing information on manatee population biology and habitat use in southwestern Florida. Recent advances in tracking technology have made this project logistically feasible and cost-effective.

Products from this work include scientific publications, fact sheets, SOFIA website postings, and spatial databases.

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/

Project Time Frame: time frame for entire project extends through 2005

Collaborators: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

Clients: U.S. Fish and Wildlife Service, U. S. Army Corps of Engineers, South Florida Water Management District, National Park Service - Everglades National Park.

B. WORK PLAN

Title of Task 1: Radio Tracking Manatees to Assess the Impact of Hydrologic Changes in Southwest Florida
Task Funding: USGS Place-Based Studies Initiative, Everglades National Park
Task Leaders: James P. Reid
Phone: 352-372-2571 ext. 15
Fax: 352-374-8080
Task Status: active
Task priority: High
Time Frame for Task 2: Time period for this task extends through 2005
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 26 manatees (46 tag deployments resulting in 6,157 manatee-tracking days) between June 2000 and February 2003; 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. Five 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 sites:
http://www.fcsc.usgs.gov/posters/Manatee/Radio_Tracking_Manatees/
radio_tracking_manatees.html (updated URL: http://cars.er.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 (updated URL: http://cars.er.usgs.gov/posters/Manatee/GPS_Tag_for_Sirenians/
gps_tag_for_sirenians.html)

Field efforts planned for FY04 and FY05 include tagging additional manatees in the TTI region and, if practical, in the southern portion of ENP. Manatee movement and habitat use data collected from Whitewater Bay to Marco Island will be integrated with PBS models and associated field projects in this region. 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.

Planned Outreach:

Detailed tracking and field data are required for Task 3, ATLSS manatee model integration. Data sharing is planned with Everglades National Park for resource management needs, specifically the park's General Management Plan. Project presentations have been submitted for the 15^th Biennial Conference on the Biology of Marine Mammalogy; Project summary, annual report, and presentations for Sofia website; USGS Fact Sheet for manatee/restoration effort.

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 Leaders: Brad Stith
Phone: 352-372-2571 ext. 24
Fax: 352-374-8080
Task Status: active
Task priority: High
Time Frame for Task 3: Time period for task extends through 2005
Task Personnel: Brad Stith, Jim Reid

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 tracked 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 two major tasks: 1) continued analysis of manatee telemetry data obtained from Task 2 to support the development and parameterization of the individual-based model, and 2) development of the model in preparation to evaluate different restoration scenarios. The 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. Salinity, water temperature, water depth, and other environmental data obtained from water quality monitoring stations in the study area likely are important factors influencing the behavior of manatees. We will continue to incorporate water quality data into the telemetry data at the appropriate time intervals, and further analyze these data with multivariate statistics to investigate the importance of various factors to manatee behavior.

Development of the individual-based manatee model will continue focusing on behavioral components within the model. This ongoing effort includes simulating manatee behavior within a Monte Carlo Markov Chain framework to model the transition of manatees between different behavioral states (e.g. feeding, drinking). We expect to improve our analysis of the telemetry data and transition matrices by utilizing multi-state mark-recapture models that are able to handle gaps in the telemetry data, to provide a robust means of evaluating factors affecting shifts in behavior. Modeling of individual home ranges will incorporate new telemetry data to better reflect observed variation in home range within the model. Further evaluation of reinforcement learning models will be conducted to simulate adaptive learning in manatees, with emphasis on how they respond to positive or negative reinforcement when they are searching for freshwater. We will continue to work with USGS colleagues (R. Scheffranek and E. Patino) to link the manatee model to a hydrology model (ultimately the TIME model). In the interim, we plan to simulate salinities along the network of creeks, rivers, and canals used by manatees using a technique demonstrated by Doering, Chamberlain et al. (SFWMD) to relate freshwater discharge to salinity gradients at varying distances from point of discharge. As additional data is collected, the model will be refined to incorporate new insights provided by the survey and telemetry data and the response of manatees to natural environmental fluctuations and human-induced alterations.

Further descriptions of methods and procedures can be seen at the following web sites:
www.fcsc.usgs.gov/posters/posters_pending_approval/Agent_Based_Manatee_Model/
agent_based_manatee_model.html (updated URL: http://cars.er.usgs.gov/posters/Manatee/Agent_Based_Manatee_Model/
agent_based_manatee_model.html)

www.fcsc.usgs.gov/posters/Manatee/Modeling_Manatee_Movements/
modeling_manatee_movements.html (updated URL: http://cars.er.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/)

Planned Outreach:

Project presentations have been submitted for the 15^th Biennial Conference on the Biology of Marine Mammalogy; project summary, annual report, and presentations for Sofia website; USGS Fact Sheet; article in Journal of Ecological Modeling.

C. BRIEF DESCRIPTION ON HOW PROJECT TASKS SUPPORT THE DOI AND USGS EVERGLADES RESTORATION SCIENCE PLANS

Because the manatee is a Federally listed species, our work supports a variety of needs identified by the DOI for listed species, including: DOI-3.K: Southwest Florida Feasibility Study, DOI-3.O: S. Golden Gate Estates Hydrologic Restoration Project, DOI-4.A: Implementation Strategy for the Multi-species Recovery Plan, USGS 2C. Threatened and Endangered Species SG1: Habitat requirements and response to hydropattern and salinity, SG3: Establish baseline status, trends, and information needed for recovery, SG4: Monitoring tools, SG5: Predictive models. The manatee also has been specifically targeted in DOI-6.A: CERP Monitoring and Assessment Plan ("Florida manatee abundance and distribution relative to changes in fresh water flows and seagrass distribution as a result of implementation of CERP"). The manatee modeling effort supports DOI-6.A: Landscape Scale Modeling of an important flagship species of the Everglades.