Meeting Abstract

P1.60  Jan. 4  Sex Specific Morphology of Neonate Sea Turtles: Comparisons of Three Species WYNEKEN, J*; CERIANI, S; Florida Atlantic University; Florida Atlantic University jwyneken@fau.edu

Historically identifying the sex of neonate sea turtles based on gross morphology is problematic and is often based on gonad histological sections. Because of their protected species status, sex ratios were often based on limited samples. Here we describe morphological characters that are diagnostic for sex identification. We compared the gross morphology of the gonads, kidneys and reproductive ducts of hatchling and posthatchling loggerheads (Caretta caretta), green turtles (Chelonia mydas), and leatherbacks (Dermochelys coriacea). We compared the morphology of the same structures (the gonad, mesovarium or mesorchium, and the paramesonephric duct) in these three species to determine how the species differed and if the sex-specific characteristics were also definitive across sea turtle species. The paramesonephric duct characteristics reliably predicted neonate sex. The paramesonephric ducts were not as well developed and tended to be less mobile in males than in females. We found sex could rarely be distinguished using gonad gross morphology alone. Gonads were more similar in C. caretta and C. mydas. Using relative gonad size, shape, attachment and several paramesonephric duct characters together, we could most reliably discriminate males from females in all three species. The paramesonephric ducts of C. mydas and D. coriacea, are less mobile than those in C. caretta. In D. coriacea, kidneys are longer and gonads and reproductive ducts are less developed than the same structures in the cheloniid species. The ability to discriminate sexes grossly and noninvasively allows for easier empirical determination of sex ratios at the nesting beaches and allows for tracking sex ratio shifts in sea turtle populations with environmental change.