Meeting Abstract
Marine turtles exhibit temperature dependent sex determination (TSD). During critical periods of embryonic development, the nest’s thermal environment directs whether an embryo will develop as a male or as a female. Warmer sand temperatures tend to produce female-biased sex ratios. The rapid increase of global temperatures highlights the need for a clear assessment of the resulting effects on the sex ratios of these animals. Estimating hatchling sex ratios at rookeries remains imprecise due to the lack of sexual dimorphism in young marine turtles. We currently rely mainly upon laparoscopy and biopsy to verify hatchling sex; however, these are invasive methods. Histology of dead-in-nest hatchling gonads can also be used to verify hatchling sex, but this method may not provide accurate estimates of live turtle sex ratios. Additionally, in some species, morphological sex can be ambiguous, even at the histological level. The purpose of this study was to develop a technique to identify sex in loggerhead sea turtle Caretta caretta hatchlings via analysis of blood samples. This approach uses Western blots to detect the expression of several proteins known to play an important role in sex determination, such as AMH in the blood and gonadal tissue of the hatchlings. The presence of the protein was then compared to the results from laparoscopic procedures in order to validate this new approach. Developing a technique to identify the sex of turtle hatchlings through blood samples will greatly enhance our ability to reliably determine sex ratios across nesting beaches, which is a crucial step in assessing the impacts of climate change on turtle demographics.
