Stable isotopes in barnacles as a tool to understand green sea turtle (iChelonia mydas/i) regional movement patterns

摘要

Sea turtles are migratory animals that travel long distances between theirfeeding and breeding grounds. Traditional methods for researching sea turtlemigratory behavior have important disadvantages, and the development ofalternatives would enhance our ability to monitor and manage these globallyendangered species. Here we report on the isotope signatures in greensea-turtle (Chelonia mydas) barnacles (Platylepas sp.)and discuss their potential relevance as tools with which to study green seaturtle migration and habitat use patterns. We analyzed oxygen(δ18O) and carbon (δ13C) isotope ratios in barnaclecalcite layers from specimens collected from green turtles captured at thePalmyra Atoll National Wildlife Refuge (PANWR) in the central Pacific. Carbonisotopes were not informative in this study. However, the oxygen isotoperesults suggest likely regional movement patterns when mapped onto apredictive oxygen isotope map of the Pacific. Barnacle proxies couldtherefore complement other methods in understanding regional movementpatterns, informing more effective conservation policy that takes intoaccount connectivity between populations.