LEATHERBACK TURTLE MOVEMENT AND DISPERSAL FROM NESTING BEACHES IN COSTA RICA WITH IMPLICATIONS FOR MANAGEMENT AND CONSERVATION

Abstract

Electronic tagging permits movement and distribution studies of sea turtles as they traverse large distances through a dynamic ocean environment. However, little is known about the movements of early life stages at sea, a period termed the 'lost years'. I developed and tested a method for attaching an acoustic tag suitable for use on leatherback turtles that was then applied to hatchlings in Costa Rica to obtain measures of speed and directionality. This was compared with ocean currents and revealed that the hatchlings actively swam against nearshore currents, although they were still advected by them. Finally, a Poisson generalized linear model in a continuous-time Markov chain model framework was used to predict adult, post-nesting Eastern Pacific leatherback movement based on environmental drivers, such as sea surface temperature. Monthly, near real-time predictions of leatherback movement were estimated using the most recent satellite-derived environmental information to help inform conservation management strategies.