Status, population trend and genetic structure of South American fur seals Arctocephalus australis in southwestern Atlantic waters

CRESPO ENRIQUE ALBERTO; SCHIAVINI ADRIÁN CARLOS MIGUEL; GARCÍA NÉSTOR ANÍBAL; FRANCO TRECU VALENTINA; GOODALL RAE NATALIE PROSSER; RODRIGUES DIEGO; MORGANTE JOAO STENGHELL; OLIVEIRA LARISSA ROSA DE

MARINE MAMMAL SCIENCE

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2015 vol. 31 p. 866 - 890

0824-0469

The South American fur seal (SAFS), Arctocephalus australis, was severely depletedduring the 18th century. This work updates information on distribution, abundance,seasonal movements, and genetic structure along the southwestern SouthAtlantic. Its distribution in Argentine waters includes nineteen rookeries on the Patagoniancoast, Isla de los Estados, and islets of the Beagle Channel. Censuses werecarried out in rookeries from Isla Escondida to Isla de los Estados from 1996 to2014. The largest concentrations are found in Chubut, (4,500?15,500 seals) and Islade los Estados (4,500). Pups were recorded on Isla Escondida, Rasa, and Isla de losEstados. An increasing number of SAFS were recorded in northern Patagonia,including seals marked in Uruguay. Skin samples were taken from southern Brazilto Tierra del Fuego in order to evaluate population structure and demographictrends. Genetic results indicated no population subdivisions (Φst = ?0.0292, Fst =?0.00716, P > 0.05). Bayesian skyline plots constructed for the entire data set indicatedevidence of rapid population expansion discernible in Nef between the last20,000 and 17,000 yr. Genetics results and observation data from marked fur sealssupport the hypothesis of ancient gene flow and a single Atlantic population.