DOC investigates decline in sea lion pups

Department of Conservation researchers are investigating a significant decline in New Zealand sea lion pups born this breeding season.

Once found widely around the mainland coastline, the breeding population has now largely retreated to the New Zealand Sub-Antarctic islands and there is concern about the growing vulnerability of the remaining breeding colonies.

Over 85% of all breeding occurs on the Auckland Islands and DOC researchers, working on the islands this summer, are recording a 31% fall in the number of New Zealand sea lion pups born this season.

“We are not exactly sure why pup numbers have declined so significantly this year. The team on the islands are currently working to pinpoint the cause of the problem. Indications at this stage are that this is not a repeat of the bacterial epidemics that led to a decrease in the number of pups born in the past. Our researchers have however observed that there are a lot less females coming ashore to breed this year,” Simon Banks, DOC’s Marine Conservation Manager said.

“Whatever the cause, this latest setback for the breeding population highlights the vulnerability of the species.”

New Zealand sea lions face a number of natural and human threats, such as fishing and disturbance by beachgoers and dogs along the mainland coastline in the past year. DOC ultimately aims to rebuild the population to non-threatened status.

DOC researchers will remain on Auckland Islands over the coming weeks to determine the cause of the latest fall in New Zealand sea lion pup numbers and to continue their on-going research into the breeding population.

Additional information:

The New Zealand sea lion is only found in New Zealand. The estimated population is around 12,000 individuals, making it one of the rarest sea lions in the world.
Breeding is concentrated on New Zealand subantarctic islands (Auckland and Campbell islands).
Over 85% of all breeding occurs on the Auckland Islands (over 64% of pups are born on Dundas Island and 19% on Enderby Island).
There have been 3 epidemics caused by bacterial infections since 1998. Epidemics have reduced annual pup production at the Auckland Islands by 53% (1998), 32% (2002) and 21% (2003).
The New Zealand sea lion is protected under the Marine Mammal Protection Act and was declared a threatened species in 1997.

If you encounter a New Zealand sea lion:

Always stay at least 10 m away. Allow them more space if they are active, and be prepared to move away calmly.
Do not disturb seals and sea lions and keep dogs and children under control.
Never attempt to handle sea lions (or seals) as they can be aggressive and often carry diseases.
If you are concerned about the safety of a sea lion (or seal), please contact the Department of Conservation immediately on 0800 DOC HOT (0800 362 468).