Marine mammals stranded or incidentally captured on the coasts of Tierra del Fuego over a period of 32 years; species and numbers

DELLABIANCA N; GOODALL , R.N.P.; PIMPER, L.E.; RICCIALDELLI, L.; BOY C.C.

Cape Town, South Africa

Conferencia; 17th Biennial conference on the biology of marine mammals; 2007

The Society for Marine Mammalogy

In view of the International Polar Year (IPY) and the Census of Marine Life (CoML), we present a summary of the species and number of marine mammals collected in 32 years of beach surveys on the shores of Tierra del Fuego, Argentina, and surrounding areas. More strandings were found on the north coast, with its wide continental shelf, high tides (to 10.6m) and extensive mud flats exposed at low tide, rather than on the southern rocky shores. The north coast is used for artesanal shore-based nets, with an incidental take of small cetaceans each year. Of the 1430 cranial cetacean specimens, the family most numerous in the collection is the Delphinidae, with 12 species and 1058 specimens (74%), followed by the Phocoenidae, two species and 193 specimens (13.5%), the Ziphiidae, eight species with 85 specimens (5.9%), Balaenopteridae with four species (2.9%) and Physeteridae (3.5%), Balaenidae (2.9%) and Neobalaenidae (0.07%) with one species each. The species most often collected was Cephalorhynchus commersonii (688 cranial specimens, due to incidental captures), followed by Phocoena dioptrica (180), Globicephala melas (132), Grampus griseus (66), Physeter macrocephalus (50), Pseudorca crassidens (46),  Lagenorhynchus australis (44) and Lissodelphis peronii (41). The most frequent Ziphiidae were Ziphius cavirostris (23) and Mesoplodon layardii (20 specimens). The year with most specimens (101) was 1995, due to a large influx of C. commersonii, which died in nets. We also collected four species of Otarids (104 cranial specimens), five species of Phocids (74) and two Mustelids (4 specimens). Although complete specimens or skulls are preferred in museums, the collection includes postcranial skeletons (skulls missing); in view of modern studies of DNA and isotopes, such specimens are also valuable. (POSTER)