My research interests center on the biology, ecology, evolution, and conservation of marine turtles with an emphasis on temperature-dependent sex determination (TSD). The research that my students and I are conducting is multidisciplinary and includes field research with conservation programs for marine turtles, as well as laboratory studies on the physiology underlying TSD.
In regards to marine turtle conservation, we work with sea turtles and with the diamondback terrapin, a turtle that inhabits bays and salt marshes. We are currently studying its biology and developing a recovery strategy for this depleted species in Alabama. This includes the evaluation of a “headstart program” for the terrapin. We are also collaborating with a variety of state, federal, and international agencies on conservation programs for sea turtles. In these studies we are generating long-term databases for nesting beach temperatures that affect TSD, and we are evaluating hatchling sex ratios resulting from TSD. This includes studies of the Kemp’s ridley sea turtle in Mexico, the hawksbill sea turtle in the Caribbean, and the leatherback sea turtle in the Pacific. Of particular significance, we have been involved in with the Binational Kemp’s ridley recovery program for almost two decades, and have been helping facilitate the survival and recovery of this critically endangered sea turtle.
Our physiological studies focus on TSD, in which the sex of many reptiles is determined by the temperature at which the egg is incubated. TSD provides several advantages not available in other vertebrate sex determination systems, including the ability to manipulate sex by both temperature and steroid hormones. We are using the slider turtle as a model system for elucidating the physiology underlying sex determination and gonadal differentiation. The results have implications for both the biology and conservation of endangered turtles.
Finally, our long-term studies of sea turtle reproduction, sex determination, and sex ratios are revealing that sea turtles represent an optimal vertebrate model system for examining the impact of long-term changes in environmental temperature. In particular, their reproductive timing, sex determination, and embryonic development are all temperature sensitive. Thus they are extremely sensitive to thermal changes in the environment, making them an ideal “sentinel” species for examining the impact of global climate change.
Zoology, Physiology, Evolution, Conservation, Ecology, Conservation of Marine Turtles with an Emphasis on Temperature-Dependent Sex Determination
