SICB Division of Ecology and Evolution (DEE)

DEE Researchers Database Entry

Anthony C Steyermark

Population Status and Life Histories of Leatherback Sea Turtles
All sea turtle species are either endangered or threatened, and leatherbacks are no exception. Pacific leatherback populations are in worse shape than Atlantic populations, and specific reasons are unknown. But general threats to all sea turtle populations include beach development, illegal egg harvesting, and fishing practices such as shrimp trawling, drift-netting, and long-lining. As part of a multinational team, we are studying a leatherback sea turtle in Costa Rica to better understand basic life history traits and how anthropological impacts are affecting both population status and life history traits such as reproductive output and hatching success. Two studies that University of St. Thomas undergraduate Kaija Wilson is working on are examining the pattern of nest placement by individual female leatherbacks, and determining the ecological impact of leatherback nest deposition. In the first study, Kaija is asking whether females, who can nest up to ten times in one season, are depositing nests in a scattered, random, or clumped pattern. Understanding pattern of nest placement is important in development management plans in the face of beach development pressures. In the second study, Kaija is studying the transfer of energy between the marine ecosystem (the caloric content of egg deposition) and the terrestrial ecosystem (the caloric remaining energy content transferred to scavengers and predators). These results will help us understand how leatherback sea turtles contribute to a terrestrial community.