Histological evaluation of hatchling sex ratios from loggerhead sea turtle nests along the Atlantic coast of the US

SHULMAN, D.; JONES, M.; PATEL, K.; PATEL, T.; WYNEKEN, J; WIBBELS, T*; University of Alabama at Birmingham, Birmingham, AL ; University of Alabama at Birmingham, Birmingham, AL ; University of Alabama at Birmingham, Birmingham, AL ; University of Alabama at Birmingham, Birmingham, AL ; Florida Atlantic University, Boca Raton, FL; University of Alabama at Birmingham, Birmingham, AL : Histological evaluation of hatchling sex ratios from loggerhead sea turtle nests along the Atlantic coast of the U.S.

Loggerhead sea turtles possess temperature-dependent sex determination in which the incubation temperature determines the sex of the hatchling. This form of sex determination has the potential of producing biased sex ratios. Therefore, the sex ratios produced from temperature-dependent sex determination are of ecological and conservational interest. Loggerheads nesting in the southeastern U.S. represent one of the largest loggerhead populations in the world. This species nests on various beaches throughout the southeastern U.S., including beaches as far north as North Carolina and as far south as Southern Florida. The current study examined sex ratios on four beaches spanning from North Carolina to south Florida. In this study, histological analysis was used to sex hatchlings which were found dead in nests after all of the live hatchlings emerged. One to nine hatchlings per nest were collected from a total of 66 nests. Kidney/gonad tissue was preserved from each hatchling, and was then processed using standard paraffin histological procedures. Each gonad was examined microscopically to determine if it was an ovary or a testis. Males and females were identified on all four of the beaches examined, but females predominated on all beaches.

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