Nest Site Fidelity of Leatherback Turtles (Dermochelys coriacea) on Playa Grande, Costa Rica: A Statistical Analysis of Individual Nest Site Selection

Abstract

The current conservation method of relocating doomed leatherback sea turtle (Dermochelys coriacea) clutches of eggs is often used on nesting grounds to save clutches located in beach areas where they would likely be lost to tidal action. It may be, that individual turtles have intrinsic preferences for certain beach locations that enter into their selection of a nest site. This being the case, the current conservation technique of relocating doomed clutches would seem ill advised, as it might select for turtles that make poor nest site selections. The possibility of individual-specific intrinsic preference was investigated using the longitudinal set of recordings collected at Playa Grande, Costa Rica over eight seasons from 1993-2001. Of particular interest was whether consecutive selections by an individual within a season indicated an association between nest site selections. Consecutive zone selections relative to the ocean-to-vegetation axis did not suggest the presence of female-specific nest site preference. Therefore, termination of the clutch relocation program is not indicated. Consecutive section selections were, however, consistent with heterogeneous nest site selection relative to the coastal axis. This suggests some association between individual-specific nest site selections in the form of preference for a nest site located near the nest site selected previously.