Long term changes in life history traits and catches of the round sardinella, Sardinella aurita (Clupeidae), along the Senegal coast, West Africa
Résumé
The main life history traits of the round sardinella, Sardinella aurita Valenciennes 1847 were updated in Senegalese coastal waters, together with an evaluation of the captures over the last 33 years (1981–2013). In the context of global change and an increase in the average sea surface temperature along the Senegalese coast, most of the life history traits of S. aurita, such as condition factor, period of reproduction, egg sizes, relative fecundity and growth did not change significantly over the years. In contrast, the size at first sexual maturity and the absolute fecundity increased significantly, and current catches recorded less large individuals. The growth was rapid and very variable, with a longevity estimated at 6–7 years. These updated data for life history traits show that the round sardinella was fully exploited in the area, that the fishing effort for this species should be reduced, and that the minimum size (120 mm) authorized by the Senegalese fisheries code should be increased (185–200 mm) to maintain stocks along the Senegal coast.