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| Subspecies: | Unknown |
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| Est. World Population: | 100000 |
| CITES Status: | NOT LISTED |
| IUCN Status: | Least Concern |
| U.S. ESA Status: | NOT LISTED |
| Body Length: | |
| Tail Length: | |
| Shoulder Height: | |
| Weight: | |
| Top Speed: | |
| Jumping Ability: | (Horizontal) |
| Life Span: | in the Wild |
| Life Span: | in Captivity |
| Sexual Maturity: | (Females) |
| Sexual Maturity: | (Males) |
| Litter Size: | |
| Gestation Period: | |
Habitat:
New Zealand Fur Seals are sexually dimorphic, with adult males reaching twice the length and more than 2.1 times the weight of adult females. In South Australia, females reach 95% of their mean asymptotic length (137 cm) and mass (48.8 kg) by 7 and 12 years, respectively. Males reach 95% of their mean asymptotic length (170 cm) and mass (104.3 kg) by 10 and 12 years, respectively (McKenzie et al. 2007). The largest males weighed in South Australia and at the Open Bay Islands of New Zealand, were 147 kg (187 cm length, 13.5 years old), and 154 kg, respectively. Pups at birth weigh 3-4 kg and are 40-55 cm long. Males double their mass in 60–100 days and females in 80–90 days, and weigh 13–16 kg at weaning which occurs when they are 9-10 months old (Goldsworthy 2006). Pups moult into adult pelage at 3-4 months. Females become mature at 4-6 years of age, males at 8-10 years (Dickie and Dawson 2003; McKenzie et al. 2005, 2007). Generation time is 9.9 years (Wickens and York 1997).
New Zealand Fur Seals are polygynous. Males arrive at colonies in late October before females and acquire and defend territories with vocalizations, ritualized displays, and fighting. Male territories include an average of 5-8 females with the ratio of females to males varying between different colonies. The number of animals ashore at rookeries declines rapidly in January. Male vocalizations include a bark or whimper, a guttural threat, a low-intensity threat, a full threat, and a submissive call. Females growl and have a pup-attraction call that is a high-pitched wail (Crawley and Wilson 1976, Ling 1987).
Pups are born from mid-November to January, with most born in December. Oestrous occurs 7-8 days after a female gives birth, and they usually spend another 1-2 days ashore with their pup before departing and beginning a cycle of foraging trips and periods of pup attendance ashore (Goldsworthy and Shaughnessy 1994, Goldsworthy 2006). Shore attendance bouts (when pups are nursed) last ~1.7 days while foraging trips to sea increase in duration from ~3-5 days in early lactation, to 8-11 days late in lactation. However, foraging trips lasting more than 20 days are not uncommon (Goldsworthy 2006).
New Zealand Fur Seals are considered non-migratory. At sea they actively groom and raft in a variety of postures typical of southern fur seals including the “jug handle” position while sleeping at the surface. They often “porpoise” out of the water when travelling rapidly at sea. Rocky shoreline habitat with shelter, and locations more exposed to wind and weather, are preferred for haul-outs and rookeries. When hauled out in New Zealand they readily enter areas of coastal vegetation behind the shoreline (Crawley and Wilson 1976, Ryan et al. 1997).
New Zealand Fur Seals prey on a large variety of cephalopods, fishes, and birds (Fea et al. 1999, Goldsworthy et al. 2003, Lalas and Webster 2014). In South Australia, key cephalopod prey include Southern Ocean Arrow Squid and Gould’s Squid; key fish species include Redbait, Ocean Jackets, Swallowtail, and myctophids; and the most frequently taken bird species are Little Penguins and Short-Tailed Shearwaters (Page et al. 2005a). Satellite tracking studies in South Australia indicate marked spatial separation in foraging regions used by juvenile, adult female, and adult male seals. In early lactation (December to March), adult females undertake short foraging trips to mid-outer shelf waters (70-90 km from the colony), in regions associated with localized upwelling (Page et al. 2006, Baylis et al. 2008a). However, in April and May most females switch to foraging in distant oceanic waters associated with the Subtropical Front, 700-1,000 km to the south of breeding colonies, and continue foraging in these waters up until the weaning of their pups in September/October (Baylis et al. 2008a,b; Baylis et al. 2012). In contrast, adult males focus their foraging over the continental slope. Juvenile seals forage in oceanic waters where they target nocturnal surface-migrating myctophid fish (Baylis et al. 2005). Adult female and male seals both forage in the water column in relative shallow depths and near or on the bottom in deeper water. For females, benthic dives on the continental shelf in South Australia are typically to 60-80 m, while those of males on the continental slope are 100-200 m. The maximum dive durations and depths recorded for adult females are 9.3 min and 312 m, and 14.8 min and 380 m for males (Page et al. 2005b).
Predators include Killer Whales, Sharks, male New Zealand Sea Lions and possibly Leopard Seals at sub-Antarctic islands (Shaughnessy 2006).
New Zealand Fur Seals are polygynous. Males arrive at colonies in late October before females and acquire and defend territories with vocalizations, ritualized displays, and fighting. Male territories include an average of 5-8 females with the ratio of females to males varying between different colonies. The number of animals ashore at rookeries declines rapidly in January. Male vocalizations include a bark or whimper, a guttural threat, a low-intensity threat, a full threat, and a submissive call. Females growl and have a pup-attraction call that is a high-pitched wail (Crawley and Wilson 1976, Ling 1987).
Pups are born from mid-November to January, with most born in December. Oestrous occurs 7-8 days after a female gives birth, and they usually spend another 1-2 days ashore with their pup before departing and beginning a cycle of foraging trips and periods of pup attendance ashore (Goldsworthy and Shaughnessy 1994, Goldsworthy 2006). Shore attendance bouts (when pups are nursed) last ~1.7 days while foraging trips to sea increase in duration from ~3-5 days in early lactation, to 8-11 days late in lactation. However, foraging trips lasting more than 20 days are not uncommon (Goldsworthy 2006).
New Zealand Fur Seals are considered non-migratory. At sea they actively groom and raft in a variety of postures typical of southern fur seals including the “jug handle” position while sleeping at the surface. They often “porpoise” out of the water when travelling rapidly at sea. Rocky shoreline habitat with shelter, and locations more exposed to wind and weather, are preferred for haul-outs and rookeries. When hauled out in New Zealand they readily enter areas of coastal vegetation behind the shoreline (Crawley and Wilson 1976, Ryan et al. 1997).
New Zealand Fur Seals prey on a large variety of cephalopods, fishes, and birds (Fea et al. 1999, Goldsworthy et al. 2003, Lalas and Webster 2014). In South Australia, key cephalopod prey include Southern Ocean Arrow Squid and Gould’s Squid; key fish species include Redbait, Ocean Jackets, Swallowtail, and myctophids; and the most frequently taken bird species are Little Penguins and Short-Tailed Shearwaters (Page et al. 2005a). Satellite tracking studies in South Australia indicate marked spatial separation in foraging regions used by juvenile, adult female, and adult male seals. In early lactation (December to March), adult females undertake short foraging trips to mid-outer shelf waters (70-90 km from the colony), in regions associated with localized upwelling (Page et al. 2006, Baylis et al. 2008a). However, in April and May most females switch to foraging in distant oceanic waters associated with the Subtropical Front, 700-1,000 km to the south of breeding colonies, and continue foraging in these waters up until the weaning of their pups in September/October (Baylis et al. 2008a,b; Baylis et al. 2012). In contrast, adult males focus their foraging over the continental slope. Juvenile seals forage in oceanic waters where they target nocturnal surface-migrating myctophid fish (Baylis et al. 2005). Adult female and male seals both forage in the water column in relative shallow depths and near or on the bottom in deeper water. For females, benthic dives on the continental shelf in South Australia are typically to 60-80 m, while those of males on the continental slope are 100-200 m. The maximum dive durations and depths recorded for adult females are 9.3 min and 312 m, and 14.8 min and 380 m for males (Page et al. 2005b).
Predators include Killer Whales, Sharks, male New Zealand Sea Lions and possibly Leopard Seals at sub-Antarctic islands (Shaughnessy 2006).
Range:
In New Zealand, this species occurs around both the North and South Islands, with newly formed breeding colonies now established on the North Island (Bouma et al. 2008) and established and predominantly expanding breeding colonies around the entire South Island (Boren et al. 2006a). There are well established and expanding colonies also found on Stewart Island and all of New Zealand's sub-Antarctic islands. In Australia, the species occurs in the coastal waters and on the offshore islands of South and Western Australia, from just east of Kangaroo Island west to the southwest corner of the continent, and also in southern Tasmania. Small populations are establishing in Bass Strait and Victorian and southern New South Wales coastal waters (Kirkwood and Goldsworthy 2013).
The range of New Zealand Fur Seals extends south to Australia’s Macquarie Island, where males mate with Antarctic and Subantarctic Fur Seals and produce hybrid pups (Lancaster et al. 2006). Vagrants have been recorded in New Caledonia and a bone was found in a 14th century archaeological site in the Cook Islands.
The range of New Zealand Fur Seals extends south to Australia’s Macquarie Island, where males mate with Antarctic and Subantarctic Fur Seals and produce hybrid pups (Lancaster et al. 2006). Vagrants have been recorded in New Caledonia and a bone was found in a 14th century archaeological site in the Cook Islands.
Conservation:
This species is protected by law in both Australia and New Zealand. In New Zealand all marine mammals are protected by the Marine Mammals Protection Act of 1978. The New Zealand Fur Seal was listed as a Least Concerned for New Zealand Species in 2010 under the New Zealand threat classification system (Baker et al. 2010, Townsend et al. 2008).
In Australia, State Governments have jurisdiction over marine mammals within 4.8 km of the coast and each state has its own conservation legislation. The Australian Commonwealth Government has jurisdiction from 4.8 km offshore throughout the rest of the country’s 322 km Exclusive Economic Zone. Under the Australian Environment Protection and Biodiversity Conservation Act 1999, New Zealand Fur Seals are listed as protected marine species. An action plan for conservation of Australian seals was published in 1999 (Shaughnessy 1999). New Zealand Fur Seals are listed on CITES Appendix II.
In Australia, State Governments have jurisdiction over marine mammals within 4.8 km of the coast and each state has its own conservation legislation. The Australian Commonwealth Government has jurisdiction from 4.8 km offshore throughout the rest of the country’s 322 km Exclusive Economic Zone. Under the Australian Environment Protection and Biodiversity Conservation Act 1999, New Zealand Fur Seals are listed as protected marine species. An action plan for conservation of Australian seals was published in 1999 (Shaughnessy 1999). New Zealand Fur Seals are listed on CITES Appendix II.