This website provides access to New Zealand sea lion pup production estimates based on data collected at breeding sites on the Auckland Islands.

New Zealand sea lion pups

New Zealand sea lion pups, Enderby Island, Auckland Island

Explore the data

New Zealand sea lion are the only pinniped endemic to New Zealand, where they have a relatively small population (about 10 000 individuals) and a highly restricted distribution. Their population size and geographical range were heavily reduced by commercial sealers in the 19th century, restricting the main breeding areas to subantarctic islands. Since their protection in 1893, New Zealand sea lion numbers have slowly increased, with haul-out sites ranging from subantarctic waters to Stewart Island and southern South Island, including Foveaux Strait and Otago. Breeding grounds at the Auckland Islands support over 80% of the total pup production of this species. In addition to the subantarctic breeding colonies, a small population has started recolonising mainland New Zealand, with 45 pups born on the Otago coast between 1994 and 2011.

Researchers from Conservation Services Programme at Department of Conservation have been carry out annual estimates of the total pup production from the breeding sites in the Auckland Islands. Where it is practical direct counts of both live and dead sea lions pups are made and where that is not possible a estimation technique called mark recapture is used.

This website summarises the results of these pup production estimates and makes the raw observational data available for download. The data are made available under a creative commons attribution licence.

There is a separate site for New Zealand sea lion tagging and resighting data.