''Arctocephalus forsteri'' (

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...

s include the Australasian fur seal, South Australian fur seal, New Zealand fur seal, Antipodean fur seal, or long-nosed fur seal) is a species of

fur seal Fur seals are any of nine species of pinnipeds belonging to the subfamily Arctocephalinae in the family Otariidae. They are much more closely related to sea lions than Earless seal, true seals, and share with them external ears (Pinna (anatomy ...

found mainly around southern

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

and

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

. The name ''New Zealand fur seal'' is used by English speakers in New Zealand; ''kekeno'' is used in the

Māori language Māori (; endonym: 'the Māori language', commonly shortened to ) is an Eastern Polynesian languages, Eastern Polynesian language and the language of the Māori people, the indigenous population of mainland New Zealand. The southernmost membe ...

. , the common name long-nosed fur seal has been proposed for the population of seals inhabiting Australia. Although the Australian and New Zealand populations show some genetic differences, their morphologies are very similar, and thus they remain classed as a single species. After the arrival of humans in New Zealand, and particularly after the arrival of Europeans in Australia and New Zealand,

hunting Hunting is the Human activity, human practice of seeking, pursuing, capturing, and killing wildlife or feral animals. The most common reasons for humans to hunt are to obtain the animal's body for meat and useful animal products (fur/hide (sk ...

reduced the population to near-extinction.

Description

Males have been reported as large as ; their average weight is about .Harcourt, R.G., (2001)
"Advances in New Zealand mammalogy 1990–2000: Pinnipeds"
''Journal of The Royal Society of New Zealand'', Retrieved 6 October 2011 Males can be long. Females are between 30 and 50 kg (66-110 lbs) on average, and can be as long as . Newborn pups are 3.3–3.9 kg (7.3-8.6 lbs) on average, and between 40 and 55 cm (1.3-1.8 ft) long. At 290 days old males are about , and females are about . Like other

otariids An eared seal, otariid, or otary is any member of the marine mammal family Otariidae, one of three groupings of pinnipeds. They comprise 15 extant taxon, extant species in seven genus, genera (another species became extinct in the 1950s) and are ...

, they have external ears and hind flippers that rotate forward, which visibly distinguish them from

true seals True most commonly refers to truth, the state of being in congruence with fact or reality. True may also refer to: Places * True, West Virginia, an unincorporated community in the United States * True, Wisconsin, a town in the United States * ...

.Department of Conservation
"New Zealand fur seal/kekeno"
Retrieved 6 October 2011. They have a pointy nose with long pale whiskers. Fur seals are covered by two layers of fur. The coat is grey-brown on their back, and lighter on their belly. Some have white tips on longer upper hairs, which can give them a silver-like appearance. So called "Upland Seals" once found on

Antipodes Islands The Antipodes Islands (, ) are inhospitable and uninhabited volcanic islands in subantarctic waters to the south of – and territorially part of – New Zealand. The archipelago lies to the southeast of Stewart Island / Rakiura, and to the ...

and

Macquarie Island Macquarie Island is a subantarctic island in the south-western Pacific Ocean, about halfway between New Zealand and Antarctica. It has been governed as a part of Tasmania, Australia, since 1880. It became a Protected areas of Tasmania, Tasmania ...

have been claimed as a distinct subspecies with thicker furs by scientists although it is unclear whether these seals were genetically distinct.

Distribution

The species occurs in Australia and New Zealand. It is found in the coastal waters and on the offshore islands of southern Australia, from the south-west corner of

Western Australia Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...

to just east of

Kangaroo Island Kangaroo Island (, ) is Australia's third-largest island, after Tasmania and Melville Island, Northern Territory, Melville Island. It lies in the state of South Australia, southwest of Adelaide. Its closest point to the mainland is Snapper Poi ...

South Australia South Australia (commonly abbreviated as SA) is a States and territories of Australia, state in the southern central part of Australia. With a total land area of , it is the fourth-largest of Australia's states and territories by area, which in ...

, and also in southern

Tasmania Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The sta ...

and the subantarctic

. Small populations are forming in

Bass Strait Bass Strait () is a strait separating the island state of Tasmania from the Mainland Australia, Australian mainland (more specifically the coast of Victoria (Australia), Victoria, with the exception of the land border across Boundary Islet). The ...

and coastal waters of Victoria and

New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...

as far as the mid-north coast. Before the arrival of humans in New Zealand, the species bred around all the New Zealand mainland and its subantarctic islands. There are now established and expanding colonies around the entire

South Island The South Island ( , 'the waters of Pounamu, Greenstone') is the largest of the three major islands of New Zealand by surface area, the others being the smaller but more populous North Island and Stewart Island. It is bordered to the north by ...

, on

Stewart Island Stewart Island (, ' glowing skies', officially Stewart Island / Rakiura, formerly New Leinster) is New Zealand's third-largest island, located south of the South Island, across Foveaux Strait. It is a roughly triangular island with a la ...

and all of the New Zealand subantarctic islands. There are also newly established breeding colonies on the

North Island The North Island ( , 'the fish of Māui', historically New Ulster) is one of the two main islands of New Zealand, islands of New Zealand, separated from the larger but less populous South Island by Cook Strait. With an area of , it is the List ...

Behaviour

Diving

The species can "porpoise" out of the water when travelling quickly at sea. They can dive deeper and longer than any other fur seal. Females can dive for about 9 minutes and to a depth of about 312 metres, and can dive deeper and longer in autumn and winter. Males can dive for about 15 minutes to a depth of about 380 metres. On average, the species typically only dives for 1–2 minutes. When they dive for food they dive deeper during the day but shallower at night, because during the day their prey typically migrates to deeper depths and migrates back up during the night ( diel vertical migration). Arctocephalus forsteri New Zealand fur seal PC300702

Arctocephalus forsteri New Zealand fur seal PC300702

Lactating females alter their dive patterns in order to regularly care for their young. Dives are shorter, from around 9 minutes down to 5 minutes. Several longer trips may be taken at first to find patches of prey. The shorter dives then utilise these patches. Due to the differences in diving pattern between males and females, there is very little inter-sexual competition for food sources. Males typically forage over continental shelf breaks in deeper water, while females typically utilise the continental shelf as foraging grounds. It is believed that differences in diving abilities and depths could be the cause of some

sexual dimorphism Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...

between males and females. Diving behaviour by the pups begins in the months leading up to weaning, when the pups are nursing less. The pups begin to dive from the age of 6–10 months, yet weaning is known to occur between the ages of 8 and 11 months, so the young pups do not have much time to learn to forage. The pups need to progressively develop nocturnal diving skills while they still have their mothers' milk to fall back on if dives are unsuccessful. Age, physiological development, and experience are important factors for success in hunting and contribute to the development of the pups' diving ability and behaviour. This transitional period, when young pups are becoming nutritionally independent while their foraging efficiency is rather low, is a time of high risk, and mortality can be very high. Based on scat samples, it has been found that the pups start by eating

cephalopods A cephalopod is any member of the molluscan Taxonomic rank, class Cephalopoda (Greek language, Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral symm ...

and eventually making their way to fish, but this may just be a result of prey availability during different times of the year.

Communication

Males vocalise through a bark or whimper, either a guttural threat, a low-intensity threat, a full threat, or a submissive call. Females growl and also have a high-pitched pup attraction wail call. Pup-attraction calls allow communication from longer distances. Once together, females use

olfactory The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it ...

recognition to confirm the pup as their own.Ian Stirling; Observations on the Behavior of the New Zealand Fur Seal (''Arctocephalus Forsteri''), ''Journal of Mammalogy'', Volume 51, Issue 4, 30 November 1970, Pages 766–778, In males, the full neck display is a non-combative posture that functions as a threat to surrounding males by which they are able to assess each other's dominance status.

Reproduction

Females mature between 4 and 6 years old, and males mature between 8 and 10 years old. These seals are

polygynous Polygyny () is a form of polygamy entailing the marriage of a man to several women. The term polygyny is from Neoclassical Greek πολυγυνία (); . Incidence Polygyny is more widespread in Africa than in any other continent. Some scholar ...

. Males obtain and guard territory in late October before females arrive. Often females mate only once a year, and this usually occurs eight days postpartum for about 13 minutes on average. Females have a delayed implantation of the fertilised egg, so that implantation on the uterine wall does not occur for 3 months.

Gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregn ...

occurs for 9 months Females are more aggressive near the time of birth, and do not like to be approached right after birth. Females will continue to reproduce until their death which is on average between 14 and 17 years of age. Females first arrive on the shore between November and January, just a few days before giving birth, and stay close to the birth site for up to ten days. When they are close to labour they become very restless and irritable. When beginning labour, which can last as much as five hours, they lie down and toss their head in the air, straining forward on their fore flippers, lifting their hind quarters, or moving laterally, before slowly lowering their head down, a process they repeat until they finally give birth. In one study, observations of the actual birth, starting from when the pup was first seen, found an average of 2 minutes for a head-first delivery, but an average of 6.5 minutes if the pup came out tail first. Immediately after birth the mother begins frequently sniffing the newborn pup to better identify when she has to find it after a trip out to sea. Pups are fairly mature at birth, and within 60 minutes they start

suckling Breastfeeding, also known as nursing, is the process where breast milk is fed to a child. Infants may suck the milk directly from the breast, or milk may be extracted with a pump and then fed to the infant. The World Health Organization (WHO ...

for about 7 minutes. Eventually the suckling can exceed 33 minutes. The mothers may take from 45 minutes to 3 days before leaving the pups to swim, and 6–12 days to go on longer feeding trips. Even then, the mothers tend to not leave the pups for longer than 2 days. When the pups are about 21 days old they have been seen to congregate into little pods while their mothers are away. When the females return they only feed their own pups, and have been seen to be hostile toward pups that are not their own. Female seals have been documented to have a gradual increase in trips for feeding throughout

lactation Lactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process naturally occurs with all sexually mature female mammals, although it may predate mammals. The process ...

. It has been found that mothers who have sons made longer

foraging Foraging is searching for wild food resources. It affects an animal's fitness because it plays an important role in an animal's ability to survive and reproduce. Foraging theory is a branch of behavioral ecology that studies the foraging behavi ...

trips then the mothers who had daughters during the lactation period. When observing growth patterns in the male and female pups within two cohorts, it is recognised that the growth patterns are similar, however the males grow faster and are weaned off nursing heavier in some years. Suckling can occur for about 300 days. Pups start to eat solid food just before

weaning Weaning is the process of gradually introducing an infant human or other mammal to what will be its adult diet while withdrawing the supply of its mother's milk. In the United Kingdom, UK, weaning primarily refers to the introduction of solid ...

, and are eventually weaned around September, when they disperse. Pup mortality has been attributed to both natural factors and human interaction. The biggest natural cause of death for pups is starvation, followed by suffocation in the amnion, stillbirth, trampling, drowning, and predation. Human factors include the handling of pups, tagging, and human presence in general.

Diet

Their diet includes

, fish, and birds. In New Zealand, New Zealand octopus and arrow squid make up most of their cephalopod diet. Individuals located near their southern range limit have been known to eat

penguin Penguins are a group of aquatic flightless birds from the family Spheniscidae () of the order Sphenisciformes (). They live almost exclusively in the Southern Hemisphere. Only one species, the Galápagos penguin, is equatorial, with a sm ...

s as part of their diet. Stomach contents have been analysed and shown to include Australian anchovy, barracouta, '' Paralichthyes'' flounders, broadgilled hagfish,

pouched lamprey The pouched lamprey (''Geotria australis''), also known as the piharau in New Zealand's North Island, korokoro, kanakana in the South Island, or wide-mouthed lamprey, is a species in the genus ''Geotria'', which is the only genus in the family Ge ...

, red cod, school shark, and many other species.Boren, L. (2010
"Diet of New Zealand fur seals (''Arctocephalus forsteri''): a summary"
Retrieved 6 October 2011 Further analysis of otoliths from their scat show that for fish prey species,

lanternfish Lanternfish (or myctophids, from the Greek language, Greek μυκτήρ ''myktḗr'', "nose" and ''ophis'', "serpent") are small mesopelagic fish of the large family (biology), family Myctophidae. One of two families in the order Myctophiformes, ...

es composed the majority of their fish diet, followed by Australian anchovies, ahuru, and hoki. There are different factors that affect their diet, such as season, sex, breeding, surrounding colony, oceanography, and climatic patterns.

Predators

Known predators are killer whales, sharks, male New Zealand sea lions, and possibly

leopard seal The leopard seal (''Hydrurga leptonyx''), also referred to as the sea leopard, is the second largest species of seal in the Antarctic (after the southern elephant seal). It is a top order predator, feeding on a wide range of prey including cep ...

s. New Zealand sea lions are also known to target pups as their prey.Bradshaw, C.J.A., Lalas, C., & McConkey, S. (1998)
"New Zealand sea lion predation on New Zealand fur seals"
''New Zealand Journal of Marine and Freshwater Research''. Retrieved 6 October 2011 Several regurgitations by sea lions have been found to contain remains of fur seal pups, some with plastic tags previously attached to female fur seal pups.

Human impact

Before the arrival of humans, the seals bred around all of New Zealand. Hunting by the first New Zealand settlers, the

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the Co ...

, reduced their range. Commercial

from shortly after the European discovery of New Zealand in the 18th century until the late 19th century reduced the population to near extinction. Today, commercial fisheries are one of the main causes of death in New Zealand fur seals, usually by entanglement and drowning. Monitoring of these pinnipeds in the Kaikōura region found that entanglements with green trawl nets and plastic strapping tape were the most common. A little less than half of the individuals were successfully released with good chances of survival even after significant entanglement wounds. It has been estimated by the Royal Forest and Bird Protection Society that over 10,000 seals could have drowned in nets between 1989 and 1998. They are also known to have been shot by commercial and recreational fishermen, because they are assumed to interfere with fishing gear. How often these shootings occur is unknown, but pressure groups have stated that the conflict between the seals and commercial fisheries is expected to increase.MarineBio.org (2011)
"New Zealand Fur Seals, ''Arctocephalus forsteri'' at MarineBio.org"
Retrieved 6 October 2011. On 21 August 2014, two decomposing animals were found beheaded near Louth Bay in South Australia. The circumstances of their deaths were considered suspicious and an investigation followed their discovery. In 2015, several conservative members of Parliament encouraged public debate around the potential implementation of seal culling in South Australia in response to increasing interactions with South Australian commercial fisheries. , the killing of long-nosed fur seals remains an illegal act. Human activity near seal rookeries has been correlated with distress and panic, resulting in indirect deaths of pups. The use of metal cattle ear tags on pups has also been associated with a decrease in pup fitness due to incomplete healing of the tag site.

Legislative protection

Australia

In Australian Commonwealth waters, ''Arctocephalus forsteri'' is protected under the '' Environment Protection Biodiversity Conservation (EPBC) Act 1999,'' under which it is listed as a protected marine species. The species is also protected within the jurisdictions of the following Australian states: The species received protection by the creation of the 16 million

hectare The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), that is, square metres (), and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. ...

Macquarie Island Marine Park, located on the eastern side of

Macquarie island Macquarie Island is a subantarctic island in the south-western Pacific Ocean, about halfway between New Zealand and Antarctica. It has been governed as a part of Tasmania, Australia, since 1880. It became a Protected areas of Tasmania, Tasmania ...

. In 2000, the Tasmanian government extended the Macquarie Island Nature Reserve by 3 nautical miles surrounding the island.

New Zealand

In New Zealand, the species is protected by the '' Marine Mammals Protection Act 1978'', which works to conserve marine animal species; it specifies that all wild

pinniped Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammals. They comprise the extant taxon, extant families Odobenidae (whose onl ...

s cannot be touched or fed.

Gallery

Seal_0906.jpg File:Arctocephalus forsteri LC0255.jpg, South Island, New Zealand Image:Squinting seal.jpeg, coming ashore below Taiaroa Head, near

Dunedin Dunedin ( ; ) is the second-most populous city in the South Island of New Zealand (after Christchurch), and the principal city of the Otago region. Its name comes from ("fort of Edin"), the Scottish Gaelic name for Edinburgh, the capital of S ...

, New Zealand Image:Seal Cubs-Palliser Bay-20070331.jpg, pups at Palliser Bay, New Zealand Image:Castlepoint Fur Seal.jpg, at Castlepoint, New Zealand

References

Sources

External links

* New Zealand fur seal discussed on RNZ ''Critter of the Week''
28 July 2017
{{Authority control Arctocephalus Pinnipeds of New Zealand Mammals of Tasmania Mammals of Western Australia Mammals of South Australia Mammals of New South Wales Mammals of Victoria (state) Mammals described in 1828 Taxa named by René Lesson Fauna of subantarctic islands Fauna of the Campbell Islands Pinnipeds of Australia Fauna of Macquarie Island