Contribution à l’étude du régime alimentaire chez l’oursin Paracentrotus lividus (Lamack, 1816) de la zone côtière de Mostaganem

Abstract

A study of the diet in the species Paracentrotus lividus of the coastal zone of Mostaganem (Stidia, Hadjadj and Petit port), was carried out in order to have an overview of the contribution of the different trophic sources in the diet of these benthic animals. . Our results show the trophic sources of Paracentrotus lividus are very diverse, but mainly of plant origin. The diet of Paracentrotus lividus presents variability depending on the season and the sampling site. In Winter, the sea urchins studied prefer the living leaves of Posidonia (20.15%) and Ceramium sp (10.69%) to Stidia; Ulva sp (19.84%) and Sphacelaria sp (17.27%) in Hadjadj and prefer Coralina sp (22.21%) and Jania sp (21.31%) in Petit port. In Spring, these same sea urchins prefer Jania sp (22.79%) and Polysiphonia sp (18.93%) to Stidia; Ulva sp (31.77%) and Porphyridium sp (14.38%) in Hadjadj and prefer Jania sp (19.06%) and Ulva sp (15.59%) in Petit port. This study not only demonstrates the herbivorous nature of Paracentrotus lividus; but also its trophic plasticity allowing it to better adapt to the constraints of its environment.