Sex steroid concentrations in immature hawksbill turtles (Eretmochelys imbricata) in the Chagos Archipelago

Plasma estradiol_17b and androgen concentrations were evaluated as indicators of the sex of immature hawksbill turtles (Eretmochelys imbricata) captured on their foraging grounds in the Chagos Archipelago, British Indian Ocean Territory. Androgen concentrations showed the bimodal distribution demonstrated by previous studies to reflect gender differences, and indicated a sex ratio (2.75 F: 1.00 M, n = 51) significantly skewed towards female. Although E/A ratios have been successfully used to determine gender in hatchling loggerhead turtles (Caretta caretta), neither estradiol-17b concentrations nor estradiol: androgen (E/A) ratios were useful indicators of gender in the size range (35-69 cm straight carapace length) represented in the present study.
Mortimer Jeanne , Crain D .
turtles, Testosterone, Androgens, Estradiol, Sex Ratio, Cheloniidae, Eretmochelys imbricata, hawksbill turtle, Foraging populations, British Indian Ocean Territory, Central Indian Ocean