Project Summary Sheet

Study Title: Ecosystem History of the Southwest Coast-Shark River Slough Outflow Area
Study Start Date: 10/1/03 Study End Date: 9/30/07
Web Sites: No data online yet, but will be added to http://sofia.usgs.gov/flaecohist/
Location (Subregions, Counties, Park or Refuge): Everglades NP, Big Cypress Preserve, Ten Thousand Islands NWR. Monroe, Collier, and Lee Counties.
Funding Source: USGS Greater Everglades Priority Ecosystems Science (PES) Initiative
Principal Investigator(s): G. Lynn Wingard
Study Personnel: T. Cronin, D. Willard, C. Holmes, W. Orem - USGS. G. Dwyer, Duke University. Potential additions for FY04 and beyond: M. Savarese, FGCU; P. Swart, UM;
Supporting Organizations: South Florida Water Management District; Everglades National Park; Big Cypress Preserve, Ten Thousand Islands NWR
Associated / Linked Studies: Historical Changes in Salinity, Water Quality and Vegetation in Biscayne Bay; Paleosalinity as a Key for Success Criteria in South Florida Restoration.

Overview & Objective(s): One of the primary goals of the Comprehensive Everglades Restoration Plan (CERP) is to restore the natural flow of water through the terrestrial Everglades and into the coastal zones. Historically, Shark River Slough, which flows through the central portion of the Everglades southwestward, was the primary flow path through the Everglades Ecosystem. However, this flow has been dramatically reduced over the last century as construction of canals, water conservation areas and the Tamiami Trail either retained or diverted flow from Shark River Slough. The reduction in flow and changes in water quality through Shark River have had a profound effect on the freshwater marshes and the associated coastal ecosystems. Additionally, the flow reduction may have shifted the balance of fresh to salt-water inflow along coastal zones, resulting in an acceleration of the rate of inland migration of mangroves into the freshwater marshes. The objectives of this project are to document impacts of changes in salinity, water quality, coastal plant and animal communities and other critical ecosystem parameters on a subdecadal-centennial scale in the southwest coastal region (from Whitewater Bay, north to the 10,000 Islands), and to correlate these changes with natural events and resource management practices. Emphasis will be placed on 1) determining the amount, timing and sources of freshwater influx (groundwater vs. runoff) into the coastal ecosystem prior to and since significant anthropogenic alteration of flow; and 2) determining whether the rate of mangrove and brackish marsh migration inland has increased since 20th century water diversion and what role sea-level rise might play in the migration.

Status: Ten cores from five locations in the inner bays of the southwest coastal region of Everglades NP were collected in May 04, and processing of cores has begun. Meetings have been held, and working relationships were established with Ten Thousand NWR and Florida Gulf Coast University. Students at FGCU have begun assisting with data processing and we have provided assistance in interpretation of cores from the Estero Bay area of the southwest coast.

Recent Products: No products have been generated for the study to date; field work just began in May.

Planned Products: Open File Reports will be generated as soon as first set of core analyses are completed. Fact sheets, talks and journal articles will follow.

Specific Relevance to Information Needs Identified in DOI's Science Plan in Support of Ecosystem Restoration, Preservation, and Protection in South Florida (DOI's Everglades Science Plan) [See Plan on SOFIA's Web site: http://sofia.usgs.gov/publications/reports/doi-science-plan/]:

One of the primary DOI activities discussed in the DOI Science Plan is to “ensure that hydrologic performance targets accurately reflect the natural predrainage hydrology and ecology” (DOI Science Plan, p. 14). The primary goal of the Ecosystem History of the Southwest Coast-Shark River Slough Outflow Area study is to determine the predrainage hydrology and ecology of the southwest coastal environment. Specifically this study supports the Additional Water for Everglades National Park, the Southern Golden Gate Estates Hydrologic Restoration, and the Southwest Feasibility Study Projects, and it provides information relevant to Landscape Modeling, Invasive Exotic Plant Detection, and Monitoring and Aquatic Exotic Animals Projects. This study supports these projects by 1) conducting research to understand the predrainage hydrology, including the amount, timing and seasonality of freshwater delivered to southwest Florida historically; 2) examining the historical environmental conditions, including the linkage between hydrology (water quality and quantity), ecology, and habitats; 3) providing the modelers with data on historic conditions in order to set targets and performance measures that reflect natural hydrologic patterns; 4) providing long-term historical data on trends and cycles within the biological component of the ecosystem that can be forecasted to predict the effects of implementation of hydrologic restoration on the ecology of coastal communities; and 5) by determining the timing of introduction and spread of exotics in the southwest ecosystem and the coincident changes in the native species.

This study supports the Additional Water for Everglades National Park and Biscayne Bay Feasibility Study by addressing the questions “What were the physical and ecological conditions in . . . Shark River Slough . . .prior to drainage and modification . . .” (DOI Plan p. 63), “What are the hydrologic targets needed to mimic historic flows . . . ? (p. 63).

This study supports the Southern Golden Gate Estates Hydrologic Restoration Project by providing long-term (100-500 years) data on natural hydrologic patterns that can be used to set targets for freshwater inflows (p. 50). In addition, information on long-term changes in the biota and ongoing studies to develop our modern proxy database (used for core interpretation) will provide baseline data on the ecological responses of communities and species (p. 51).

This study supports the Southwest Feasibility Study Project by providing predrainage hydrologic and ecologic conditions that can be used to set the hydrologic targets (p. 50). The results of the core analyses will provide data on temporal and spatial patterns within the estuaries and the linkage between hydrologic conditions and ecological responses; this information can be used by the modelers (p. 50) and to determine what faunal or floral species might be used as key indicators (p. 51).

In addition, the study contributes to the Landscape Modeling project by providing historical ecological data on trends and cycles that can be forecasted to predict the effects of implementation of hydrologic restoration on the ecology of coastal communities. This addresses questions of the impact of increased flow (p. 63), and expected faunal and floral responses (p. 64, p. 79, p. 80). The study also contributes to the Invasive Exotic Plant Detection and Monitoring and Aquatic Exotic Animals Projects by determining the temporal and spatial distribution of exotics and changes in native species coincident with introduction (p. 118).

Key Findings: No significant findings to date. First cores were collected in May 2004 and processing has just begun.