Diversity and status of sea turtle species in the Gulf of Guinea islands

Abstract

In West Africa, the Gulf of Guinea islands are important nesting places for four sea turtle species. The Green turtle (Chelonia mydas), the Hawksbill (Eretmochelys imbricata), the Olive Ridley (Lepidochelys olivacea) and the Leatherback (Dermochelys coriacea) turtles nest on Bioko’s southern beaches. The Green, Hawksbill and Leatherback turtles breed on Principe and São Tome. The Leatherback turtle nests, at least, on Annobén. The Leatherback turtle is reported on the four islands for the first time, and the Olive Ridley turtle for Bioko. Bioko is probably the most important island in terms of number of species and nesting individuals; the Green turtle being the most abundant species. However, the nesting places are at present restricted to barely 20 km along the coastline. On Principe and São Tome, the most common species is the Hawksbill turtle. Sea turtle nesting populations are being severely depleted on the four islands. The main causes of overexploitation are the meat and egg trade on Bioko and the Hawksbill shell-craft trade on São Tome and Principe.