A pointy nosed seal with long whiskers, visible external ears and body covered with two layers of fur. Fur seals look almost black when wet, but may look lighter when dry.
Adult females: average length 1.2m, weight 40 kg.
Adult males: average length 1.6m, weight 160 kg.
Range
The New Zealand fur seal is found throughout New Zealand, western and southern Australia.
Population
In New Zealand, minimum estimates of the population are 50 – 60,000, but this is almost certainly an underestimate. Recent work in Otago has shown there was a population increase of 25% per year between 1982 and 1994 and surveys in 1995 indicated this was continuing.
A similar rate of increase has been noted in the Nelson/Marlborough region and also in the Subantarctic Bounty Islands. Since 1991, fur seals have recommenced breeding on the North Island. In Australia latest estimates are 30 – 35,000 with an annual increase of 16 to 19%.
Although there are no estimates of population growth available for Southland, a nationwide survey in the 1970’s showed fur seals in Southland accounted for over 40 % of the total New Zealand population or 70% if the sub-antarctic islands are included.
Predators
Large sharks and killer whales are the main predators of seals. Hooker’s sea lions may occasionally take juvenile fur seals in the sub-antarctic islands but this has not been reported on the mainland.
Diet
A survey is currently under way into the diet of south coast fur seals. Early results show that south coast seals mainly eat arrow squid, octopus, barracuda, jade mackerel and hoki mostly off the continental shelf in depths greater than 22 metres.
Foraging Patterns
The New Zealand fur seal dives deeper and longer than any other fur seal. Female fur seals on the West Coast are known to (occasionally) dive deeper than 238 m, and for as long as I I minutes. Off the Otago Peninsula in summer, they feed almost exclusively at night (88 – 97% of dives), as deep as 163m with a maximum recorded dive time of 6.2 minutes.
Most dives are however of 1-2 minutes. Most of their prey are species which follow a vertical migration, i.e. they come nearer the surface in the middle of the night, and sink back to deeper depths during the day. The seals appear to follow these migrations when they forage. Their summer foraging is concentrated over the continental shelf, or near the slope. They will dive continuously from sundown to sunrise. In autumn and winter, they dive much deeper with many dives deeper than 100m. At least some females dive deeper than 240m, and from satellite tracking they may forage up to 200km beyond the continental slope in water deeper than 1000m.
Human Impact
New Zealand fur seals ranged around New Zealand before the arrival of humans. They were taken as food by Maori. The onset of European sealing saw heavy exploitation to the point where they were almost wiped out.
In 1894 they were given full protection.