Project Summary Sheet

Project: Influence of Hydrology on Life-History Parameters of Common Freshwater Fishes from Southern Florida

Web Sites: http://everglades.fiu.edu; http://www.fcsc.usgs.gov (see http://cars.er.usgs.gov/)

Location: Central Everglades

Principal Investigators: 1) William F. Loftus, 305.242.7835, bill_loftus@usgs.gov; 2) Leo Nico, 352. 378.8181, leo_nico@usgs.gov

Project Personnel: 1) Joel Trexler, 305.348.1966, trexlerj@fiu.edu; 2) Jeff Herod, 352.378.8181, jeff_herod@usgs.gov; 3) Tim Connert, 305.348.4032, connertt@fiu.edu

Other Supporting Organizations: NPS and FFWCC. Mesocosm at ENP

Associated Projects: ATLSS (USGS study); Everglades Restudy (RESTORE); Fish populations of South Florida Canals (USGS study).

Overview & Status: The objectives are to establish age-size relationships for 11 species of fishes, construct life-tables, study reproductive phenology and fecundity, and apply the data to simulation models and to field data time-series. Work on this project began in late 1999 and is divided into large-fish and small-fish segments. We have made three collections of the large-bodied fishes from canal sites, taken otoliths from over 700 specimens, and set up a dozen large tanks in the mesocosm facility in ENP. There we have used pit-tags to individually mark several dozen fishes of five target species that have been injected with oxytetracycline to place a mark on their hard tissues. These fishes will be maintained in the mesocosm for over one year to validate the deposition of annual or semiannual rings. We are determining the best method of classifying the ova of the fishes as to stage of readiness. We have dissected the gonads from more than 800 fishes for this analysis. For the small fish segment, we have sorted collections of fishes from the two hydroperiod sites and are dissecting them to collect the tiny otoliths, and to perform preliminary examinations of the gonads. We are also beginning to raise captive fishes for aging validation. Field collections will continue for two years and lab/statistical analyses for another year.

Needs & Products: New project - only trimester reports and a draft Fact sheet have been produced. The final products will consist of a series of 3-4 publications that will describe the life-history characteristics of 11 Everglades fishes. This is new scientific information.

Application to Everglades Restoration: The results, in the form of data, model rules, and life-tables, will be used to improve the ATLSS fish model used to suggest and evaluate restoration alternatives. The information will aid in interpreting the time series of fish field data used in research and monitoring before and during restoration. The data are also needed to develop performance measures for CERP.