Embryo mortality and hatch success in In situ and translocated leatherback sea turtle Dermochelys coriacea eggs

Abstract

At Sandy Point National Wildlife Refuge, St Croix, US Virgin Islands, natural beach erosion results in the loss of 45–60% of the leatherback sea turtle Dermochelys coriacea eggs laid there per annum. In a 4-year study (1982–1985), 31·4–68·1% of the eggs laid annually (312 of 582 total clutches) were collected at oviposition and reburied in stable beach zones in an effort to mitigate losses to erosion. Reburial did not significantly increase the proportion of eggs per clutch that failed to develop, the proportion of eggs that contained pre-term dead embryos, the occurrence of embryonic deformity, or the risk of depredation for eggs or hatchlings. However, a consistently larger proportion of pipped, dead hatchlings in clutches that had been moved reduced overall hatch success in translocated as compared to in situ clutches (53·7% versus 64·1%, respectively). Collection and reburial of otherwise doomed eggs resulted in a net gain of c. 6650 hatchlings over 4 years.