| Summary: | Twenty-seven odontocete species are identified as occupying subantarctic and Antarctic habitat covered by the 1994 IWC-established Southern Ocean Sanctuary. Twenty-one species are autochthonous in showing a regular, apparently year-round, presence: Physeter macrocephalus, Kogia breviceps, Orcinus orca, Globicephala melas edwardii, Lagenorhynchus cruciger, Lagenorhynchus obscurus, Lissodelphis peronii, Cephalorhynchus commersonii, Cephalorhynchus hectori, Tursiops truncatus, Delphinus delphis, Phocoena dioptrica, Hyperoodon planifrons, Berardius arnuxii, Ziphius cavirostris, Tasmacetus shepherdi, Mesoplodon layardii, Mesoplodon traversii, Mesoplodon grayi, Mesoplodon bowdoini and Mesoplodon hectori . Six species are considered vagrants into the Sanctuary: Kogia sima, Grampus griseus, Steno bredanensis, Mesoplodon peruvianus, Mesoplodon densirostris and Mesoplodon mirus . One ziphiid, Mesoplodon ginkgodens was found contiguously. However, the vagrant status of several mesoplodonts is preliminary, and some may be autochthonous. Increasing information on external features of beaked whales allows a higher percentage of odontocetes positively identified to species during sighting surveys. More odontocete species were found, or occurred farther south, in the Southern Ocean Sanctuary, than expected. Overall, much more is known about odontocetes of the Southern Ocean now than in 1994 as a result of the establishment of a number of research programmes. Odontocetes play an important part in the Antarctic polar ecosystem and are subject to different pressures than the baleen whales.
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