ARGOS Tracking Data of Fur Seals from Macquarie Island in 1997-1999

Brief description

The populations of fur seals on Australia's two subantarctic islands were exterminated by uncontrolled sealing in the 19th century. Only in the latter half of the 20th century have populations commenced recovering. This project provides key information on the status and trends of recovering fur seal populations in the Southern Ocean, including information on the distribution of foraging effort, food and energy requirements, oceanographic determinants of demographic performance, ecological interactions with commercial fisheries, the extent, trends, processes and implications of hybridisation at Macquarie Island, and the status and trends in numbers of the threatened subantarctic fur seal.

This dataset represents ARGOS tracking data of fur seals from Macquarie Island during 1997-1999. The tracking data are comprised of 28 data profiles.

Taken from the abstract of the referenced paper:

Antarctic Arctocephalus gazella and subantarctic Arctocephalus tropicalis fur seals breed sympatrically at Macquarie Island. The two species have different lactation strategies, the former rearing its pup in 4 months and the latter taking 10 months. The diet and at-sea foraging behaviour of these sympatric species was compared during the austral summer period when their pup rearing period overlapped. The prey of the two fur seal species was very similar, with fish dominating the diet. Themyctophid, Electrona subaspera, was the main prey item (93.9%) in all months of the study. There were no major differences in the diving behaviour between species. Both species foraged north of the island parallel to the Macquarie Ridge. Foraging activity was concentrated at two sites: (i) within 30 km north of the island; and (ii) at 60 km north. Most locations for overnight foraging trips were within 10 km of the colonies. The different lactation strategies of A. gazella and A. tropicalis allowed for flexibility in foraging behaviour. At Macquarie Island, the local marine environmental conditions have resulted in similar foraging behaviour for both species.

Lineage

Progress Code: completed

Statement: See the referenced papers for more information.