Rôle trophique du Poulpe commun, Octopus vulgaris, chez les Elasmobranches de la côte du Sénégal (Atlantique oriental tropical). Comparaison avec les espèces des côtes tunisiennes (Méditerranée centrale)

Abstract

      To explain the abundance of the common Octopus, Octopus vulgaris, in the Senegalese marine waters, we have estimated interesting to know the role of the species in the local ecosystem by the way of its trophic relations versus the biological environment and its potential predators, especially the collected elasmobranch fishes. The stomach contents of 237 elasmobranch specimens belonging to 13 species were studied. The observed elasmobranchs especially ingest teleosts and crustaceans and sometimes cephalopods. O. vulgaris were only identified in the stomach contents of two species. These observations do not corroborate previous data provided by the ichtyological literature concerning elasmobranchs caught in various marine areas of the world where they were considered to be cephalopod predators. This is more particularly the case for the species from the Tunisian coasts (Central Mediterranean). In their stomach contents were found cephalopods, among them O. vulgaris.