Etude démographique de deux espèce de Gastéropodes Prosobranche (Patella rustiqua Linna eus, 1758) et (Patella caerulea Linna eus, 1758 ) de la côte de Mostaganem (Stidia et Picard).

Abstract

A spatio-temporal démographique study of two gastropod species Patella caerulea (Linnaeus, 1758) and Patella rustica (Linnaeus, 1758) was carried out on the coast of Mostaganem at two stations Stidia and Picard. Several biometric parameters such as Length (Ln), Geometric Mean (MG) of the shell and the pulpit Dry weight of each individual sampled were calculated. The results of our study showed that for P. caerulea MG it seems more correlated with the dry weight of individuals of P. caerulea, however it is not always the case in P. rustica. Furthermore, P. caerulea is more abundant in the mediolateral than P. rustica. The demographic analysis shows that the station of Picard seems to recruit limpet’s larvae before the station of Stidia according to the influence of surface currents. Finally, recruitments events of P. caerulea and P. rustica found in the middle of May shows that the reproduction period for these two limpets is spread out over a much wider period than the winter season.