Sperm Whale Diet in New Zealand - Implications for Conservation

Stomach contents of 19 mature sperm whales 18 males and one female that stranded on New Zealand beaches between the mid 1990s and 2004 were examined identified and measured. Three of the stomachs were empty. All other samples consisted almost entirely of cephalopod beaks. A total of 23223 cephalopod beaks (10647 upper and 12576 lower) representing at least 36 species in 17 families were found in the remaining 16 stomachs. Non-Cephalopod remains in the stomachs of sperm whales stranded in New Zealand included limited quantities of fish salps crustacean exoskeletons a copepod some wood and sand. The present investigation represents the most comprehensive study of the diet of sperm whales in New Zealanad since the 1960s. The results show that oceanic squid of the families Histioteuthidae Cranchiidae Onychoteuthidae and Octopoteuthidae are the most comon remains found in the stomachs of sperm whales stranded on New Zealand beaches with the families Onychoteuthidae Histioteuthidae Octopoteuthidae and Archi­teuthidae being the most important by estimated weight in whale diet and the families Cranchiidae Pholidoteuthidae and Ancistrocheiridae secondarily so.