Snow leopard

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This article is about the cat. For other uses, see Snow Leopard (disambiguation).
Snow leopard
Uncia uncia.jpg
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Felidae
Subfamily: Pantherinae
Genus: Panthera
Species: P. uncia
Binomial name
Panthera uncia
(Schreber, 1775)
Subspecies

See text

Snow leopard range.png
Range map
Synonyms
  • Felis irbis Ehrenberg, 1830 (= Felis uncia Schreber, 1775), by subsequent designation (Palmer, 1904).[2]
  • Uncia uncia Pocock, 1930

The snow leopard (Panthera uncia syn. Uncia uncia) is a large cat native to the mountain ranges of Central and South Asia. It is listed as endangered on the IUCN Red List of Threatened Species because as of 2003, the size of the global population was estimated at 4,080-6,590 adults, of which fewer than 2,500 individuals may reproduce in the wild.[1]

Snow leopards inhabit alpine and subalpine zones at elevations from 3,000 to 4,500 m (9,800 to 14,800 ft). In the northern range countries, they also occur at lower elevations.[3]

Taxonomically, the snow leopard was classified as Uncia uncia since the early 1930s.[2] Based on genotyping studies, the cat has been considered a member of the genus Panthera since 2008.[1][4] Two subspecies have been attributed, but genetic differences between the two have not been settled.[1]

The snow leopard is the National Heritage Animal of Pakistan.[5]

Description

Skull, as illustrated by N. N. Kondakov

Snow leopards are slightly smaller than the other big cats but, like them, exhibit a range of sizes, generally weighing between 27 and 55 kg (60 and 121 lb), with an occasional large male reaching 75 kg (165 lb) and small female of under 25 kg (55 lb).[6][7] They have a relatively short body, measuring in length from the head to the base of the tail 75 to 130 cm (30 to 50 in). However, the tail is quite long, at 80 to 100 cm (31 to 39 in), with only the domestic-cat-sized marbled cat being relatively longer-tailed.[8][9] They are stocky and short-legged big cats, standing about 60 cm (24 in) at the shoulder.[10]

Snow leopards have long, thick fur, and their base color varies from smoky gray to yellowish tan, with whitish underparts. They have dark grey to black open rosettes on their bodies, with small spots of the same color on their heads and larger spots on their legs and tails. Unusually among cats, their eyes are pale green or grey in color.[8][9]

Snow leopards show several adaptations for living in a cold, mountainous environment. Their bodies are stocky, their fur is thick, and their ears are small and rounded, all of which help to minimize heat loss. Their paws are wide, which distributes their weight better for walking on snow, and have fur on their undersides to increase their grip on steep and unstable surfaces; it also helps to minimize heat loss. Snow leopards' tails are long and flexible, helping them to maintain their balance, which is very important in the rocky terrain they inhabit. Their tails are also very thick due to storage of fat and are very thickly covered with fur which allows them to be used like a blanket to protect their faces when asleep.[9][11]

The snow leopard has a short muzzle and domed forehead, containing unusually large nasal cavities that help the animal breathe the thin, cold air of their mountainous environment.[8]

The snow leopard cannot roar, despite possessing partial ossification of the hyoid bone. This partial ossification was previously thought to be essential for allowing the big cats to roar, but new studies show the ability to roar is due to other morphological features, especially of the larynx, which are absent in the snow leopard.[12][13] Snow leopard vocalizations include hisses, chuffing, mews, growls, and wailing.

Snow leopards were only reclassified as a member of the Panthera genus (big cats) following a genetic study by Mr Brian Davis, Dr Gang Li and Professor William Murphy in 2009. This study showed that Snow leopards actually evolved alongside tigers and not leopards as previously thought.

Naming and etymology

Ounce

Both the Latinised genus name, Uncia, and the occasional English name "ounce" are derived from the Old French once, originally used for the European lynx. "Once" itself is believed to have arisen by back-formation from an earlier word "lonce" – the "l" of "lonce" was construed as an abbreviated "la" ("the"), leaving "once" to be perceived as the animal's name. This, like the English version "ounce", became used for other lynx-sized cats, and eventually for the snow leopard.[14][15]

The snow leopard is also known in its native lands as "wāwrīn pṛāng" (Pashto: واورين پړانګ‎), "shan" (Ladakhi), "irves" (Mongolian: ирвэс), "bars" or "barys" (Kazakh: барыс [ˈbɑrəs]), "ilbirs" (Kyrgyz: Илбирс), "barfānī chītā" (Hindi, Urdu: برفانی چیتا) and "him tendua" (Sanskrit, Hindi: हिम तेन्दुआ).

According to the American Heritage Dictionary, the origin of the word panthera is unknown. A folk etymology derives the word from the Greek πάν pan ("all") and thēr (beast of prey) because they can hunt and kill almost anything. It was proposed to have come ultimately into Greek from a Sanskrit word meaning "the yellowish animal" or "whitish-yellow". The Greek word πάνθηρ, pánthēr, referred to all spotted Felidae generically.

Distribution and habitat

Snow leopard at the Toronto Zoo

The snow leopard is distributed from the west of Lake Baikal through southern Siberia, in the Kunlun Mountains, in the Russian Altai mountains, Sayan and Tannu-Ola Mountains, in the Tian Shan, across Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan to the Hindu Kush in eastern Afghanistan, Karakoram in northern Pakistan, in the Pamir Mountains, and in the high altitudes of the Himalayas in India, Nepal, and Bhutan, and the Tibetan Plateau. In Mongolia, it is found in the Mongolian and Gobi Altai and the Khangai Mountains. In Tibet, it is found up to the Altyn-Tagh in the north.[3][16]

Potential snow leopard habitat in the Indian Himalayas is estimated at less than 90,000 km2 (35,000 sq mi) in the states of Jammu and Kashmir, Uttarakhand, Himachal Pradesh, Sikkim, and Arunachal Pradesh, of which about 34,000 km2 (13,000 sq mi) is considered good habitat, and 14.4% is protected. In the beginning of the 1990s, the Indian snow leopard population was estimated at roughly 200-600 individuals living across about 25 protected areas.[3]

In summer, snow leopards usually live above the tree line on mountainous meadows and in rocky regions at altitudes from 2,700 to 6,000 m (8,900 to 19,700 ft). In winter, they come down into the forests to altitudes around 1,200 to 2,000 m (3,900 to 6,600 ft). Snow leopards prefer rocky, broken terrain, and can travel without difficulty in snow up to 85 cm (33 in) deep, although they prefer to use existing trails made by other animals.[8]

Taxonomy and evolution

Closeup of a male

The snow leopard was first described by Schreber in 1775 on the basis of an illustration. Schreber named the cat Felis uncia and assumed that it ranges in Barbary, Persia, East India, and China.[17]

In 1854, Gray proposed the genus Uncia, to which he subordinated the snow leopard under the name Uncia irbis.[18] Pocock corroborated this classification, but attributed the scientific name Uncia uncia. He also described morphological differences to the Panthera cats.[19]

Based on genotyping studies, the snow leopard has been considered a member of the genus Panthera since 2008.[4] Despite the common name given to the snow leopards, the tiger is considered its sister species, with the leopard being a more distant relative.[20][21]

The snow leopard subspecies U. u. baikalensis-romanii was proposed for a population living in the southern Transbaikal region, which requires further evaluation.[2][22] Authors of the Handbook of the Mammals of the World recognize two subspecies, namely U. u. uncia occurring in Mongolia and Russia; and U. u. uncioides living in western China and the Himalayas.[23]

Ecology and behavior

The snow leopard is solitary, except for females with cubs. They rear them in dens in the mountains for extended periods.[citation needed]

An individual snow leopard lives within a well-defined home range, but does not defend its territory aggressively when encroached upon by other snow leopards. Home ranges vary greatly in size. In Nepal, where prey is abundant, a home range may be as small as 12 km2 (5 sq mi) to 40 km2 (15 sq mi) and up to five to 10 animals are found here per 100 km2 (39 sq mi); in habitats with sparse prey, though, an area of 1,000 km2 (386 sq mi) supports only five of these cats.[12]

Like other cats, snow leopards use scent marks to indicate their territories and common travel routes. These are most commonly produced by scraping the ground with the hind feet before depositing urine or scat, but they also spray urine onto sheltered patches of rock.[8]

Snow leopards are crepuscular, being most active at dawn and dusk.[9] They are known for being extremely secretive and well camouflaged.

Hunting and diet

Showing teeth at Taronga Zoo, Australia

Snow leopards are carnivores and actively hunt their prey. Like many cats, they are also opportunistic feeders, eating whatever meat they can find, including carrion and domestic livestock. They can kill animals more than three to four times their own weight, such as the bharal, Himalayan tahr, markhor and argali, but will readily take much smaller prey, such as hares and birds.[11] They are capable of killing most animals in their range with the probable exception of the adult male yak. Unusually among cats, snow leopards also eat a significant amount of vegetation, including grass and twigs.[8]

The diet of the snow leopard varies across its range and with the time of year, and depends on prey availability. In the Himalayas, it preys mostly on bharals (Himalayan blue sheep), but in other mountain ranges, such as the Karakoram, Tian Shan, Altai and Tost Mountains of Mongolia, its main prey consists of Siberian ibex and argali, a type of wild sheep, although this has become rarer in some parts of the snow leopard's range.[9][24][25] Other large animals eaten when available can include various types of wild goats and sheep (such as markhors and urials), other goat-like ruminants such as Himalayan tahr and gorals, plus deer, red panda, wild boars, and langur monkeys. Smaller prey consists of marmots, woolly hares, pikas, various rodents, and birds such as the snow cock and chukar.[9][11][24]

Considerable predation of domestic livestock occurs,[1] which brings it into direct conflict with humans. However, even in Mongolia, where wild prey have been reduced and interactions with humans are common, domestic stock (mainly domestic sheep) comprise less than 20% of the diet of species, with wild prey being taken whenever possible.[25] Herders will kill snow leopards to prevent them from taking their animals.[11] The loss of prey animals due to overgrazing by domestic livestock, poaching, and defense of livestock are the major drivers for the decreasing population of the snow leopard. The snow leopard has not been reported to attack humans, and appears to be the least aggressive to humans of all big cats. As a result, they are easily driven away from livestock; they readily abandon their kills when threatened, and may not even defend themselves when attacked.[8]

Snow leopards prefer to ambush prey from above, using broken terrain to conceal their approach. They will actively pursue prey down steep mountainsides, using the momentum of their initial leap to chase animals for up to 300 m (980 ft). They kill with a bite to the neck, and may drag the prey to a safe location before feeding. They consume all edible parts of the carcass, and can survive on a single bharal for two weeks before hunting again. Annual prey needs appears to be 20–30 adult blue sheep.[1][8]

Reproduction and life cycle

Cubs at the Cat Survival Trust, Welwyn, UK

Snow leopards are unusual among large cats in that they have a well-defined birth peak. They usually mate in late winter, marked by a noticeable increase in marking and calling. Snow leopards have a gestation period of 90–100 days, so the cubs are born between April and June. Oestrus typically lasts from five to eight days, and males tend not to seek out another partner after mating, probably because the short mating season does not allow sufficient time. Paired snow leopards mate in the usual felid posture, from 12 to 36 times a day.[8]

The mother gives birth in a rocky den or crevice lined with fur shed from her underside. Litter sizes vary from one to five cubs, but the average is 2.2. The cubs are blind and helpless at birth, although already with a thick coat of fur, and weigh from 320 to 567 g (11.3 to 20.0 oz). Their eyes open at around seven days, and the cubs can walk at five weeks and are fully weaned by 10 weeks.[8] Also when they are born, they have full black spots which turn into rosettes as they grow to adolescence.[citation needed]

The cubs leave the den when they are around two to four months of age, but remain with their mother until they become independent after around 18–22 months. Once independent, they may disperse over considerable distances, even crossing wide expanses of flat terrain to seek out new hunting grounds. This likely helps reduce the inbreeding that would otherwise be common in their relatively isolated environments. Snow leopards become sexually mature at two to three years, and normally live for 15–18 years, although in captivity they can live for up to 21 years.[8]

Conservation status

Numerous agencies are working to conserve the snow leopard and its threatened mountain ecosystems. These include the Snow Leopard Trust, the Snow Leopard Conservancy, the Snow Leopard Network, the Cat Specialist Group and the Panthera Corporation. These groups and numerous national governments from the snow leopard’s range, nonprofits and donors from around the world recently worked together at the 10th International Snow Leopard Conference in Beijing. Their focus on research, community programs in snow leopard regions, and education programs are aimed at understanding the cat's needs, as well as the needs of the villagers and herder communities affecting snow leopards' lives and habitat.[26][27]

Population and protected areas

Snow leopard at zoo d'Amnéville, France, showing the thickly furred tail
Snow leopard

The total wild population of the snow leopard was estimated at 4,510 to 7,350 individuals.[28] Many of these estimates are rough and outdated.[1]

In 1972, the International Union for Conservation of Nature (IUCN) placed the snow leopard on its Red List of Threatened Species as globally "Endangered"; the same threat category was applied in the assessment conducted in 2008.

There are also approximately 600 snow leopards in zoos around the world.[9]

Range Country Habitat Area
(km2)
Estimated
Population[1]
Afghanistan 50,000 100–200?
Bhutan 15,000 100–200?
China 1,100,000 2,000–2,500
India 75,000 200–600
Kazakhstan 50,000 180–200
Kyrgyzstan 105,000 150–500
Mongolia 101,000 500–1,000
Nepal 30,000 300–500
Pakistan 80,000 200–420
Tajikistan 100,000 180–220
Uzbekistan 10,000 20–50
Snow leopard in the San Diego Zoo

Protected areas:

Much progress has been made in securing the survival of the snow leopard, with them being successfully bred in captivity. The animals usually give birth to two to three cubs in a litter, but can give birth to up to seven in some cases.

A "surprisingly healthy" population of snow leopards has been found living at 16 locations in the isolated Wakhan Corridor in northeastern Afghanistan, giving rise to hopes for survival of wild snow leopards in that region.[34]

Relationships with humans

Snow leopard in the media

Planet Earth has a segment on snow leopards. The series took some of the first video of snow leopards in the wild, and also featured a snow leopard hunting a markhor.[35]

Nisar Malik, a Pakistani journalist, and cameraman Mark Smith (who had worked on the Planet Earth segment) spent a further 18 months filming snow leopards in the Hindu Kush for the BBC film Snow Leopard – Beyond the Myth.[36]

In the 2013 film The Secret Life of Walter Mitty, photojournalist Sean O'Connell (played by Sean Penn) is shown photographing snow leopards in Afghanistan.

In Philip Pullman's His Dark Materials, published in 1995, Lord Asriel's dæmon is a snow leopard named Stelmaria.

Tai Lung, the main antagonist of the 2008 film Kung Fu Panda is a snow leopard.

Snow leopard in heraldry

Snow leopards have symbolic meaning for Turkic people of Central Asia, where the animal is known as irbis or bars, so it is widely used in heraldry and as an emblem.

The snow leopard (in heraldry known as the ounce) (Aq Bars) is a national symbol for Tatars and Kazakhs: a snow leopard is found on the official seal of the city of Almaty, and a winged snow leopard is found on Tatarstan's coat of arms. A similar leopard is featured on the coat of arms of North Ossetia-Alania. The Snow Leopard award was given to Soviet mountaineers who scaled all five of the Soviet Union's 7000-meter peaks. In addition, the snow leopard is the symbol of the Girl Scout Association of Kyrgyzstan.

As a national emblem

Attacks on humans

Snow leopard attacks are rare. Only two instances are known of snow leopard attacks on humans.[38] On July 12, 1940, in Maloalmaatinsk gorge near Alma-Ata (Almaty), a rabid snow leopard attacked two men during the day and inflicted serious injuries on both.[39] In the second case, not far from Alma-Ata, an old, toothless, highly emaciated snow leopard unsuccessfully attacked a passerby in winter; it was captured and carried to a local village.[40] There are no other records of any snow leopard attacking a human being.[41][42]

References

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External links