Stomach contents of cetaceans stranded in the Canary Islands 1996–2006

Stomach contents were analysed from 23 cetaceans, including individuals of 12 species from the families Delphinidae, Physeteridae, Kogiidae and Ziphiidae, stranded between 1996 and 2006 in the Canary Islands. Cephalopod mandibles (beaks) were found in 21 stomachs and fish remains (otoliths and jaw bones) appeared in 4 stomachs. Two stomachs contained only eye lenses. Cephalopods eaten by dolphins were mainly from the families Ommastrephidae, Sepiidae and Enoploteuthidae, whereas whales had mainly taken specimens of the oceanic squid families Histiotheutidae and Cranchiidae. Fish remains included a pelagic species (i.e. garfish, Belone belone) in dolphin stomachs and bathypelagic (i.e. black scabbard fish, Aphanopus carbo, lantern fish, Lampadena luminosa) and demersal species (Lophius sp.) in a pygmy sperm whale (Kogia breviceps) stomach. Most of the prey species identified are not of commercial interest but one of the sperm whales (Physeter macrocephalus) contained a fishing hook among the stomach contents. Five (22%) of the cetaceans examined had also plastic debris in their stomachs, with big plastic items being taken by deep diving teuthophagous whales.