Reproductive and developmental synchrony in female Lepidochelys olivacea

The reproductive behavior and movements of arribada nesting olive ridley turtles (Lepidochelys olivacea) were studied during the 1990 and 1991 nesting seasons (September through November) at Nancite Beach, Santa Rosa National Park, Guanacaste, Costa Pica. Females that normally emerge synchronously once a month on Nancite Beach to oviposit delayed oviposition in response to a period of very heavy rainfall. Females retained oviducal eggs for 63 days and emerged synchronously to oviposit at Nancite Beach after the rain had ceased. Egg retention in L. olivacea appears to be an adaptation which enables delayed oviposition when environmental conditions are unsuitable and may also facilitate reproductive synchrony. We suggest that preovipositional arrest of developing embryos may have occurred while oviducal eggs were retained.