The diet of the Antarctic fur seal Arctocephalus gazella at the South Orkney Islands in ten consecutive years

• Published in: Polar Biology
• Main Authors: Casaux, Ricardo Jorge, Juares, Mariana Alejandra, Carlini, Alejandro, Corbalán, Aldo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer
• Subjects: ANTARCTIC FUR SEAL; ANTARCTICA; DIET COMPOSITION; SOUTH ORKNEY ISLANDS; https://purl.org/becyt/ford/1.6; https://purl.org/becyt/ford/1; Antarctic; The Antarctic; Patagonia; San Juan; Argentino; Argentina; South Orkney Islands; Laurie; Ricardo; Laurie Island; Antarc*; Antarctic Fur Seal; Antarctic Krill; Antarctica; Arctocephalus gazella; Dirección Nacional del Antártico; Instituto Antártico Argentino; Polar Biology
• Online Access: http://hdl.handle.net/11336/56400

To improve the knowledge on the Antarctic fur seal foraging behavior, evaluate whether changes in its diet are associated with changes in prey availability, and evaluate whether fisheries had negative impacts on Antarctic fur seal populations, a total of 1359 scats of non-breeding males were collected in ten consecutive sampling periods between 1994 and 2003 at Laurie Island, South Orkney Islands. Antarctic krill was the most numerous prey throughout the sampling period followed in importance by fish prey. Antarctic krill also predominated by reconstructed mass, except during 1994 and 1998 when penguins were the most important prey, and during 1995 when fish dominated. Among fish, demersal-benthic species (mainly Gobionotothen gibberifrons, Chaenocephalus aceratus and Chionodraco rastrospinosus) dominated the diet except in 1997, 1998, 1999 and 2002 when myctophids (mainly Gymnoscopelus nicholsi and Electrona antarctica) were the most important fish prey. In seasons when fish dominated the diet, the diet was primarily comprised of demersal species. Although our results are in overall agreement with previous studies, the contribution to the diet of the main preys changed throughout the sampling period, probably in parallel with changes in prey abundance. According to historical results on fish consumption, the fisheries carried out in the past have had negative impacts on seal populations from the South Orkney Islands. Fil: Casaux, Ricardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina Fil: Juares, Mariana Alejandra. Consejo Nacional de Investigaciones Científicas y ...