Meeting Abstract
P2.95 Jan. 5 Natural Sex Ratios from Field Nests of Gopher Tortoises (Gopherus polyphemus) in Southeast Georgia ROSTAL, David C*; WOODS, Carrie S; WIBBELS, Thane; Georgia Southern University; Georgia Southern University; Univ. of Alabama at Birmingham Rostal@georgiasouthern.edu
The gopher tortoise (Gopherus polyphemus) has been demonstrated to possess TSD in laboratory studies. However, no studies have attempted to see how these laboratory results can be applied to understanding the process in the field across multiple years. The gopher tortoise is reported to have a pivotal temperature of approximately 29oC similar to many other emydid turtles on the east coast of the United States. The gopher tortoise is restricted to upland habitats and lays hardshelled eggs which require low moisture. We set HOBO temperature dataloggers in gopher tortoise nests from 1997 to 2006 on Fort Stewart Army Reservation (FSAR). FSAR has large remnant colonies of gopher tortoises which display good reproduction and high hatching success. All hatchling were reared in captivity and sexed using laparoscopy. Field nests results were compared with datalogger results from the same habitat to determine the suitability of monitoring ground temperature. Sex ratios produced were compared with temperature data and compared to the adult sex ratio. Adult sex ratio for gopher tortoises in Georgia is 1:1 (n = 376). Individual nest temperatures are compared with sex ratios produced. Mixed sex ratios were observed in many nests while other nests displayed 100% male or female hatchlings.
