Marine Turtles Nesting Activity Assessment and Trend along the Central African Atlantic Coast for the Period of 1999-2008

Abstract

Four marine turtle species commonly nest along the Atlantic coast of Central Africa: leatherback (Dermochelys coriacea), olive ridley (Lepidochelys olivacea), hawksbill (Eretmochelys imbricata) and green (Chelonia mydas) turtles. The most important regional status assessment to date is reported in this study integrating data from 40 nesting sites from Cameroon to the Republic of Congo. The description of marine turtle nesting seasons has been performed and annual nesting activity estimated for each studied nesting site. Thus, we were able to present the spatial pattern of nest distribution throughout the studied nesting beaches. Moreover, leatherback and olive ridley Central African stocks have been assessed and we show hereby their nesting trend over these 8 years. Leatherbacks trend is decreasing in Gabonese coast while increasing in Congolese one. The pattern is not understood and need more attention, as Gabon coast shares the highest worldwide aggregation for this species. Ridleys trend is decreasing in Congo and stable elsewhere in Central Africa. Finally, the necessity of a regional and international framework for marine turtle conservation and future assessment priorities are discussed.