embyonic development of the loggerhead seaturtle

Sampling eggs from different islands attempted to eliminate bias associated with latitude and the impact of human populations. These data were examined to determine at which stage of development failure most often occurred. Embryos were staged based on their size and stages were converted into the corresponding days of incubation. Fertility was defined by the presence of an embryo, embryonic disk, blood streaks or metabolized yolk and albumin. Categories of development included: undetermined, infertile, fertile (with no embryo present), embryonic disk, early embryonic death (0.1-1.0 cm SCL), mid-embryonic death (1.1-2.0 cm) and late embryonic death (2.0-5.0 cm). The straight-line carapace length of recovered embryos was recorded.

The eggs were dissected, observed macroscopically and the contents were classified according to the amount of development. All eggs used for this study were intact and immediately preserved in 10 % formalin or 70 % ethanol. First, that egg failure was not caused by infertility and second that embryonic death occurred most frequently during the first ten days of development. These locations represent the Northern, central and Southern portions of the barrier island chain. Unhatched eggs from fully incubated wild nests were collected from Wassaw, Sapelo and Jekyll Islands on the coast of Georgia during the 2004, 20 nesting seasons. The goal of this project was to evaluate egg failure in the threatened loggerhead sea turtle (Caretta caretta).

Embyonic development of the loggerhead seaturtle