PS 22-89 - Sea turtle nesting in Everglades National Park: Integrating beach surveys, satellite tracking, and genetics

Wednesday, August 10, 2016
ESA Exhibit Hall, Ft Lauderdale Convention Center
Andrew G. Crowder1, Michael S. Cherkiss2 and Kristen M. Hart2, (1)Contractor to USGS WARC, Cherokee Nation Technologies, Davie, FL, (2)Wetland and Aquatic Research Center, U.S. Geological Survey, Davie, FL
Background/Question/Methods

Despite state-wide monitoring efforts on mainland Florida beaches to map and enumerate nesting effort for marine turtles, very little focus has been on tagging and sampling turtles on nesting beaches in Everglades National Park (ENP). These remote sandy beaches of ENP are comprised of 18 individual beaches that cover a total length of 56,650 m. Intense surveys of these beaches in the 1970s and 1980s indicated use by federally-threatened loggerheads (Caretta caretta) for nesting. Recent genetic analyses of loggerheads in the U.S. Atlantic have distinguished four subpopulations in the region. However, it is currently unclear to which subpopulation loggerheads nesting in ENP belong, as they have not been included in these analyses. We initiated night surveys to intercept, sample, and tag nesting loggerheads at Cape Sable in ENP during July 2014. We documented turtle nests and false crawls, sampled each turtle for genetics, and outfitted individuals with satellite-tracking devices to document movements and habitat use patterns during breeding and non-breeding seasons. The Cape Sable marine turtle rookery was once thought to be among the largest remaining rookeries for loggerheads, and one that may be least-impacted by humans and development. 

Results/Conclusions

We collected genetic samples and deployed satellite tags on seven nesting loggerheads; none had any previous tags from other research projects. Analysis of the genetic samples revealed the presence of the A 2.1 haplotype in all individuals. Satellite-tracking revealed the spatial extent of loggerhead habitat-use areas during the critical inter-nesting period, as well as post-nesting foraging sites that included Everglades National Park, Florida Keys National Marine Sanctuary, Florida Bay, Gulf of Mexico, the southern Bahamas, and off the northeastern coast of Cuba. These data will allow us to further define movement corridors and foraging habitats for this little studied population, providing a new understanding of regional connectivity of disparate sites that are important for this threatened species.