projects > life history, ecology, and interactions of everglades crayfishes in response to hydrological restoration > project summary
Project Summary Sheet
U.S. Geological Survey, Greater Everglades Science Program: Place-Based Studies
Fiscal Year 2002 Project Summary Sheet
Location (Subregions & Counties): Central Everglades; Miami-Dade, Broward
Funding (Source): Critical Ecosystem Studies Initiative (CESI) funding to USGS-BRD, Florida Caribbean Science Center
Project Personnel: A. Noble Hendrix, 206.985.3609, firstname.lastname@example.org
Supporting Organizations: Collecting permits NPS and FFWCC
Associated / Linked Projects: ATLSS (USGS-BRD funding through CESI); RECOVER
Overview & Status: This six-year study to investigate the life histories and ecology of major aquatic invertebrate species in the Everglades has been completed. The original proposal to study the Everglades crayfish (Procambarus alleni) was of limited scope that included the collection of density and biomass data for the crayfish across a hydrological gradient. A dramatic finding was the recognition of a second species of crayfish, Procambarus fallax, in the study marshes. This species was previously known to range southward only into Palm Beach County. It was overlooked or misidentified in previous studies. We expanded the study to (1) obtain seasonal abundance information in habitats spanning a hydrological gradient in Everglades National Park and Big Cypress National Preserve; (2) describe life-history parameters pertinent to ATLSS modeling, including burrowing seasonality, fecundity, growth, and diet, of each species; (3) study the interspecific interactions that explain the distributional patterns evident from field sampling through mesocosm experiments; (4) and use the data to create simulation models of crayfish distribution and dynamics in the system to evaluate restoration actions. This study provided the first database of the relative abundance, life histories, ecology, and standing stocks of the two crayfish species in several habitat types from south Florida. The empirical data are the first available for the two species that inhabit southern Florida, making them scientifically valuable. We have used a retrospective analysis of archived samples to show that P. fallax and P. alleni distributions and abundances are dynamically related to the hydrological conditions of an area. This fact makes crayfish distribution a good predictor for use in the restoration, and will be used as a performance measure.
Needs & Products: Products: 1) Hendrix, A. N. and W. F. Loftus, 2000. Distribution and relative abundance of the crayfishes Procambarus alleni (Faxon) and P. fallax (Hagen) in southern Florida. Wetlands 20: 194-199; 2) Fact sheet is under construction; 3) Comparative life-history manuscript is nearly ready for review; 4) Poster on web at http://sofia.usgs.gov/. More work is needed to determine the causes for the species shifts that are related to hydroperiod. Subsequent work to develop an ATLSS model has received funding and is progressing.
Application to Everglades Restoration: The results are intended to improve the ATLSS fish model, and to create an ATLSS crayfish model, to suggest and evaluate restoration alternatives. The species-composition data provide an indicator of hydroperiod that will be useful in monitoring and have been proposed to be used as a performance measure for RECOVER. This work has also led to crayfish being proposed as an indictor to be monitored with RECOVER funding. Products: 1) Hendrix, A. N. and W. F. Loftus. 2000. Distribution and relative abundance of the crayfishes Procambarus alleni (Faxon) and P. fallax (Hagen) in southern Florida. Wetlands 20: 194-199; 2) Fact sheet is under construction; 3) Comparative life-history manuscript is nearly ready for review; 4) Poster on web at http://sofia.usgs.gov/. More work is needed to determine the causes for the species shift related to hydroperiod.