Meeting Abstract

P2.95  Friday, Jan. 4  Effect of daily water treatment on hatchling sex ratios in a turtle with temperature-dependent sex determination LEBLANC, A.M.*; WIBBELS, T.; Univ. of Alabama, Birmingham; Univ. of Alabama, Birmingham leblanc@uab.edu

A variety of reptiles have temperature-dependent sex determination (TSD) in which incubation temperature appears to be the main factor affecting sex determination. Previous studies have suggested that the hydric environment may also influence sex determination under certain laboratory conditions in species with TSD. However, other studies suggest that this relationship remains uncertain. Additionally, the sex ratios produced from sea turtle nests on natural nesting beaches do not always match the sex ratios predicted from laboratory studies using constant incubation temperatures, thus suggesting that other factors may be influencing sex determination. The effect of water treatments on sex determination was examined in the current study using the red-eared slider turtle, Trachemys scripta. Eggs were incubated at a temperature (29.1 ^oC) that produced predominantly females. Eggs were randomly assigned to control or experimental groups. The experimental groups received a daily water treatment (0.77 ml per egg per day) during the temperature sensitive period. The control groups produced approximately 90% females (n = 53). The experimental groups (n = 84) produced significantly more males than the control groups (P < 0.05 or greater). The results suggest that TSD can be influenced when eggs are exposed to water treatments. This could have implications when examining sex ratios from natural nesting beaches that are periodically exposed to rain.