New Zealand (Hooker’s) sea lions are based around the Auckland Islands and Campbell Island with approximately 150 based on the New Zealand mainland on the southeast coast of the South Island from Oamaru southwards. The only breeding on the mainland is in the Otago region where it began with a single pup in the 1993/94 season and now averages 4 pups per year – almost all related to the original female. New Zealand sea lions were once found up to the top of the North Island, but after hunting by Maori and Europeans, were almost extinct by the mid-1800s. The population is now estimated at 10 000 – 12 000, but is currently in decline. New Zealand sea lions are similar to most other sea lion species in their length (up to 3m) and weight (up to 400kg). Adult males are dark grey or brown in colour with a mane of longer, thicker hair around the neck. Females are much smaller (up to 2m and 180kg) and lighter in colour with no mane, similar to juvenile males. Like other eared seals they lift their body off the ground and are able to walk on their flippers. This means they can reach speeds of up to 20km/hr on land. They use the front flippers for swimming as they chase a wide variety of prey including a wide range of fish, squid, octopus, crabs, and occasionally seabirds and fur seals.
Males fight for territories in November and mating occurs about one week after females give birth, usually in December or early January. Pups are generally weaned at 10-11 months old but may remain with the mother if she does not have a new pup. Female sea lions may start breeding as early as three years old and can live for as long as 28 years. It is uncertain when males become mature but are not likely to be big enough to hold a breeding territory until they are about eight years old. Sea lions prefer sandy beaches but may travel up to 1km inland and as they are usually unafraid of people this can lead to contention. Sea lions are currently protected from all harassment under the Marine Mammals Protection Act, 1978. They are considered a threatened species due to their limited breeding range making them vulnerable to disease. The greatest human impact is through fisheries bycatch, though several sea lions have been shot since their return to the New Zealand mainland.