Low-Temperature Protection of Marine Turtle Eggs During Long-Distance Relocation

Abstract

Movement of marine turtle eggs, between about 3 hours and 3 weeks after oviposition, often results in substantial embryonic mortality. Eggs of the loggerhead turtle (Caretta caretta), which were cooled to 7-10°C within a few hours of oviposition, were relocated 1077 km in 14 h before being set at temperatures within the normal incubation range (26, 28 and 32°C). The percentage of viable embryos and hatchlings produced from these eggs was comparable to that of undisturbed eggs laid in natural nests. The incubation period and the sex ratio of the hatchlings, observed for each temperature regime, were unaffected by the initial cooling. Cooling C. caretta eggs effectively arrests early embryonic development, thereby extending the period during which eggs can be relocated without causing movement-induced mortality. This procedure is applicable in situations where turtle eggs must be transported for research or hatchery management purposes.