New contribution to the knowledge of the mesopelagic cephalopod community off the western Canary Islands slope

Abstract

B.V.Cephalopods are a key component of the marine food webs. Nevertheless, the deep-sea cephalopods are still poorly studied worldwide. The distribution and composition of the mesopelagic cephalopod's community in different deep scattering layers from the Canary Islands (North-eastern Atlantic) are described here. The results of a mesopelagic fishing survey (CETOBAPH) at the western slopes of three islands of the Canary archipelago (El Hierro, La Palma and Tenerife) are reported. A total of 3,717 specimens of 17 families were caught at different acoustic scattering layers previously detected in depth. The pelagic families Pyroteuthidae, Enoploteuthidae, Onychoteuthidae and Cranchiidae comprised 91% of the total cephalopod catch. Species belonging to these families were responsible for the differences found in the cephalopod community assembly between the shallow sound scattering layers, situated at night in the epipelagic zone and deep sound scattering layers in the mesopelagic zone. No differences were observed in the cephalopod community composition among the three sampled islands. The species richness among islands were similar with 32, 30 and 31 species collected for El Hierro, La Palma and Tenerife, respectively. These results suggest the existence of vertical but no horizontal segregation of small cephalopod species at the mesoscale level in the Canary Islands.