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The tiger (Panthera tigris) is a mammal of the Felidae family, the largest of four "big cats" in the Panthera genus.[1] Native to the mainland of Asia, the tiger is an apex predator and the largest feline species[2] in the world,[3][4] comparable in size to the biggest fossil felids.[5] The Bengal Tiger is the most common subspecies of tiger, constituting approximately 80% of the entire tiger population, and is found in India, Bangladesh, Bhutan, Myanmar and Nepal. It has disappeared from much of its former distribution including the Caucasus, Java and Bali.

The tiger is an endangered species, with the majority of the world's tigers now living in captivity.[6] Several subspecies are extinct and others critically endangered. Tigers have featured in ancient mythologies and folklore, and continue to be depicted in modern films and literature, as well as appearing on flags, coats of arms and as mascots for sporting teams. It is the national animal of India,[7] among other countries.


Subspecies[]

There are nine recent subspecies of tiger, three of which are extinct, one of which is almost certain to become extinct in the near future, and five of which still occur.[1] Their historical range (severely diminished today) ran through Russia, Siberia, Iran, Afghanistan, India, China and south-east Asia, including the Indonesian islands. These are the surviving subspecies, in descending order of wild population:

  • The Bengal tiger or the Royal Bengal tiger (Panthera tigris tigris) is found in parts of India, Bangladesh, Nepal, Bhutan and Myanmar. It lives in varied habitats: grasslands, subtropical and tropical rainforests, scrub forests, wet and dry deciduous forests and mangroves. The Indian government's estimated population figure for these tigers is between 3,100 and 4,500, some 3,000 of which are found in India alone. However, many Indian tiger conservationists doubt this number, seeing it as overly optimistic. The number of Bengal tigers in India may be fewer than 2,000,[8] as most of the collected statistics are based on pugmark identification, which often gives a biased result. Even though this is the most 'common' tiger, these tigers are under severe pressure from both habitat destruction and poaching. In 1972, India launched a massive wildlife conservation project, known as Project Tiger, to protect the depleting numbers of tigers in India. The project helped increase the population of these tigers from 1,200 in the 1970s to 3,000 in the 1990s and is considered as one of the most successful wildlife conservation programs. At least one Tiger Reserve (Sariska) has lost its entire tiger population to poaching.[9] Males in the wild usually weigh 205 to 227 kg (450–500 lb), while the average female will weigh about 141 kg.[10] However, the northern Indian and the Nepalese Bengal tigers are supposed to be somewhat bulkier than those found in the south of the Indian Subcontinent, with males averaging around 520 lbs (236 kg).[11]
  • The Indochinese tiger (Panthera tigris corbetti), also called Corbett's tiger, is found in Cambodia, China, Laos, Myanmar, Thailand, and Vietnam, preferring to exist in forests in mountainous or hilly regions. Estimates of its population vary between 1,200 to 1,800, with only several hundred left in the wild, but it seems likely that the number is in the lower part of the range; it is considered Endangered. The largest current population is in Malaysia, where illegal poaching is strictly controlled, but all existing populations are at extreme risk from habitat fragmentation and inbreeding. In Vietnam, almost three-quarters of the tigers killed provide stock for Chinese pharmacies. Also, the tigers are seen by poor natives as a resource through which they can ease poverty. Indochinese tigers are smaller and darker than Bengal tigers. Males weigh from 150–190 kg (330–420 lb) on average while females are smaller at 110–140 kg (242–308 lb). Their diet consists of wild pigs, cattle and deer; The Indochinese tiger is a carnivore.[12]
  • The Malayan tiger (Panthera tigris jacksoni), exclusively found in the southern (Malaysian) part of the Malay Peninsula, was not considered a subspecies in its own right until 2004. The new classification came about after a study by Luo et al. from the Laboratory of Genomic Diversity Study,[13] part of the National Cancer Institute of the United States. Recent counts showed there are 600–800 tigers in the wild, making it the third largest tiger population behind the Bengal tiger and the Indochinese tiger. The Malayan tiger is a national icon in Malaysia, appearing on its coat of arms and in logos of Malaysian institutions, such as Maybank.
  • The Sumatran tiger (Panthera tigris sumatrae) is found only on the Indonesian island of Sumatra. The wild population is estimated at between 400 and 500, seen chiefly in the island's national parks. Recent genetic testing has revealed the presence of unique genetic markers, indicating that it may develop into a separate species, if it is not made extinct.[14] This has led to suggestions that Sumatran tigers should have greater priority for conservation than any other subspecies. Habitat destruction is the main threat to the existing tiger population (logging continues even in the supposedly protected national parks), but 66 tigers were recorded as being shot and killed between 1998 and 2000, or nearly 20% of the total population. The Sumatran tiger is the smallest of all living tiger subspecies. Adult males weigh between 100–130 kg (220–286 lb), females 70–90 kg (154–198 lb). Their small size is an adaptation to the thick, dense forests of the Sumatra island where they reside, as well as the smaller-sized prey. On February 3 2007 a pregnant Sumatran Tiger was caught by people from Rokan Hilir village at Riau province. Indonesian fauna conservation officials are planning to transfer her to the Bogor Safari Park in Java.
  • The Amur tiger (Panthera tigris altaica), also known as the Siberian, Manchurian or North China tiger, is confined completely to the Amur region in far eastern Siberia, where it is now protected. The last two censuses (1996 and 2005) found 450–500 Amur tigers within their single and more or less continuous range making it one of the largest undivided tiger populations in the world. Considered the largest subspecies, with an average weight of around 227 kg (500 lb) for males.[15] The Amur tiger is also noted for its thick coat, distinguished by a paler golden hue and a smaller number of stripes. The Amur tiger is the largest and heaviest of all naturally-occurring felines. A six-month old Amur tiger can be as big as a fully grown leopard.
  • The South China tiger (Panthera tigris amoyensis), also known as the Amoy or Xiamen tiger, is the most critically endangered subspecies of tiger and will almost certainly become extinct. It is one of the smaller tiger subspecies. The length of the South China tiger ranges from 2.2–2.6 m (87–104 in) for both males and females. Males weigh between 127 and 177 kg (280–390 lb) while females weigh between 100 and 118 kg (220–260 lb). It seems likely that the last known wild South China tiger was shot and killed in 1994, and no live tigers have been seen in their natural habitat for the last 20 years. In 1977, the Chinese government passed a law banning the killing of wild tigers, but this appears to have been too late to save the subspecies. There are currently 59 known captive South China tigers, all within China, but these are known to be descended from only six animals. Thus, the genetic diversity required to maintain the subspecies may no longer exist, making extinction a possibility. Currently, there are breeding efforts to reintroduce these tigers to the wild by 2008.

Extinct subspecies[]

  • The Balinese tiger (Panthera tigris balica) has always been limited to the island of Bali. These tigers were hunted to extinction—the last Balinese tiger is thought to have been killed at Sumbar Kima, West Bali on 27 September 1937; this was an adult female. No Balinese tiger was ever held in captivity. The tiger still plays an important role in Balinese Hindu religion.
  • The Javan tiger (Panthera tigris sondaica) was limited to the Indonesian island of Java. It now seems likely that this subspecies became extinct in the 1980s, as a result of hunting and habitat destruction, but the extinction of this subspecies was extremely probable from the 1950s onwards (when it is thought that fewer than 25 tigers remained in the wild). The last specimen was sighted in 1979.
  • The Caspian tiger or Persian Tiger (Panthera tigris virgata) appears to have become extinct in the late 1960s, with the last reliable sighting in 1968, though it is thought that such a tiger was last shot dead in the south-eastern-most part of Turkey in 1970. Historically it ranged through Afghanistan, Iran, Iraq, Pakistan, the former Soviet Union, and Turkey. The Caspian tiger was a large subspecies and reached nearly the dimensions of the Bengal Tiger. The heaviest confirmed weight of a male was 240 kg. The ground colour was comparable to that of the Indian subspecies, but differed especially in the tight, narrow striping pattern. The stripes were rather dark grey or brown than black. Especially during the winter, the fur was relatively long. The Caspian tiger was one of two subspecies of tiger (along with the Bengal) that was used by the Romans to battle gladiators and other animals, including the Barbary Lion. The Romans traveled far to capture exotic beasts for the arena.


Biology and behaviour[]

Adult tigers are fiercely territorial. The size of a tiger's home range mainly depends on prey abundance, and, in the case of male tigers, on access to females. A tigress may have a territory of 20 km² while the territories of males are much larger, covering 60–100 km². While females can at times be aggressive towards other females, their territories can overlap and they do tolerate each other. Males, however, are usually intolerant of other males within their territory. Because of their aggressive nature, territorial disputes can be violent, and may end in the death of one of the males. To identify his territory, the male marks trees by spraying urine and anal gland secretions on trees as well as by marking trails with scat. Males show a grimacing face, called the Flehmen response, when identifying a female's reproductive condition by sniffing their urine markings.

Male tigers can mingle easily with females in their territories and will even share kills. George Schaller observed a male tiger share a kill with two females and four cubs. Females are often reluctant to let males near their cubs, but Schaller saw that these females made no effort to protect or keep their cubs from the male. This suggests that the male might have been the father of the cubs. In contrast to male lions, male tigers will allow the females and cubs to feed on the kill first. Females will also share kills, even more so than the males. They are also much more tolerant of sharing kills with individuals of the same sex.

Tigers have been studied in the wild using a variety of techniques. The populations of tigers were estimated in the past using plaster casts of their pugmarks. In recent times, camera trapping has been used instead. Newer techniques based on DNA from their scat are also being evaluated. Radio collaring has also been a popular approach to tracking them for study in the wild.

Hunting and diet[]

File:037tiger.jpg

Tiger dentition. The large canines are used to make the killing bite, but they tear meat when feeding using the carnassial teeth

In the wild, tigers mostly feed on larger and medium sized animals. Sambar, gaur, water buffalo, chital, wild boar and nilgai are the tiger's favored prey in India. In Siberia the main prey species are Mandchurian elk, wild boar, sika deer, roe deer and musk deer. In Sumatra rusa deer, wild boar and Malayan tapir are preyed on. In the former Caspian tiger's range saiga, camels, Caucasian Wisent, yak and wild horses were preyed. Like many predators, they are opportunistic and will eat much smaller prey such as as monkeys, peacocks, hares and fish.

They also may kill such formidable predators as dholes, leopards, and pythons. Tigers have been known to kill even crocodiles on occasion,[16][17][18] although predation is rare and the predators typically avoid one another. Siberian tigers and brown bears are a serious threat to each other and usually avoid confrotation; however, tigers will kill bear cubs and even some adults on occasion. Bears (Asiatic black bears and brown bears) make up 5-8% of the tigers diet in the Russian Far East. [19] Sloth bears are quite aggressive and will sometimes drive young tigers away from their kills although the opposite happens as well and in some cases Indian tigers even prey on sloth bears.[19]

Adult elephants are too dangerous to tigers to serve as common prey, but conflicts between elephants and tigers do sometimes take place. A case where a tiger killed an adult female Indian rhino has been observed.[20] Young elephant and rhino calves are occasionally taken.

Tigers sometimes prey on domestic animals such as dogs, cows, horses and donkeys. These individuals are termed cattle-lifters or cattle-killers in contrast to typical game-killers. Especially old and injured tigers have been known to attack humans and are then termed as man-eaters, which often leads to them being captured, shot or poisoned. Man-eaters have been a recurrent problem for India, especially in Kumaon and Garhwal in the early part of the twentieth century, notable accounts of the hunting of which have been written by [[Jim Corbett]. The Sundarbans mangrove swamps of Bengal, where some healthy tigers have been known to hunt humans, have had a higher incidence of man-eaters.


Habitat[]

Tigers are found in a variety of habitats, including both tropical and evergreen forests, woodlands, grasslands, rocky country, swamps, and savannas. The Caspian tiger was also found in steppes and mountainous areas. Compared to the lion, the tiger prefers more dense vegetation, for which its camouflage is ideally suited, and where a single predator is not at a disadvantage compared to a pride. Among the big cats, only the tiger and jaguar are strong swimmers; tigers are often found bathing in ponds, lakes, and rivers.

A tiger marks its territory with a strong mix of urine and other bodily fluids marked on trees, bushes, rocks, and soil, as well as by scratches made on trees. This territory can vary from only a few square miles in area, to over fifty square miles. It is a common trend of these territories that a males will encompass ground taken by a female. Tigers defend their territory fiercely and actively; out of all of the big cats, the tiger has killed the most humans, and much of the time, these humans are killed because they ventured into an area that is part of a tiger's territory.[21]

Conservation[]

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File:1990tiger.PNG

Tiger headcount in 1990

Humans are the tiger's most significant predator, as tigers are often poached illegally for their fur. Many Indian tigers' parts found their way to Tibet, where they were widely used for making traditional costumes.

At the Kalachakra Tibetan Buddhist festival in south India in January 2006 the Dalai Lama preached a ruling against using, selling, or buying wild animals, their products, or derivatives. The result when Tibetan pilgrims returned to Tibet afterwards was much destruction by Tibetans of their wild animal skins including tiger and leopard skins used as ornamental garments. It has yet to be seen whether this will result in a long-term slump in the demand for poached tiger and leopard skins.[22][23][24]

Their bones and nearly all body parts are used in traditional Chinese medicine for a range of purported uses including pain killers and aphrodisiacs. The use of tiger parts in pharmaceutical drugs in China is already banned. China has even made some offenses in connection with Tiger poaching punishable by death. Though it has been made illegal, China's wealthy businessmen are known to eat Tiger penis as they feel it is an aphrodisiac. [1].Poaching for fur and destruction of habitat have greatly reduced tiger populations in the wild. A century ago, it is estimated there were over 100,000 tigers in the world but the population has dwindled to between 7,000 and 5,000 tigers.[25] Some estimates suggest the population is even lower, with some at less than 2,500 mature breeding individuals, with no subpopulation containing more than 250 mature breeding individuals.[26] The threat of extinction is mitigated somewhat by the presence of some 20,000 tigers currently in captivity, [27] although parts of the captive population (eg. the 4-5,000 animals in China's commercial tiger farms) is of very low genetic diversity and can be of little use in keeping the species alive.

Relation with humans[]

Traditional Asian medicine[]

Tiger parts are used in traditional Chinese medicines. Many people in China believed that tiger parts have medicinal properties. There is no scientific corroboration to these beliefs. Although all trade in tiger parts is illegal under CITES and a domestic trade ban has been in place in China since 1993 there is still a number of tiger farms in the country specializing in breeding the cats for profit from meat and other tiger products. It is estimated that between 4000 and 5000 captive-bred, semi-tame animals live in these farms today. [28] [29]

Controversial release of a hand reared hybrid Tigress in the wild[]

Tara, a hand-reared (supposedly Bangal) tigress acquired from Twycross Zoo in England in July 1976 was trained by Billy Arjan Singh and released to the wild in Dudhwa National Park, India with the permission of India’s then Prime Mininster Indira Gandhi in an attempt to prove the experts wrong that zoo bred hand reared Tigers can ever be released in the wild with success. In the 1990s, some tigers from Dhudhwa were observed which had the typical appearance of Siberian tigers: white complexion, pale fur, large head and wide stripes. With recent advances in science it was subsequently found that Siberian Tigers genes have polluted the otherwise pure Bengal Tiger gene pool of Dudhwa National Park. It was proved later that Twycross Zoo had been irresponsible and maintained no breeding records and had given India a hybrid Siberian-Bengal Tigress instead. Dudhwa tigers constitute about 1% of India's total wild population, but the possibility exists of this genetic pollution spreading to other tiger groups, at its worst, this could jeopardize the Bengal tiger as a distinct subspecies[30][31][32][33][34][35][36][37][38][39].


External links[]

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  1. 1.0 1.1 Template:Citeweb
  2. Crossbreed ligers can grow larger than Tigers, but they are not a species with its own breeding population.
  3. Template:Cite web
  4. Lesson 5, Kids for Tigers.
  5. Cat Specialist Group.
  6. Vital Statistics: Tigers
  7. Template:Cite web
  8. Task force says tigers under siege
  9. Template:Cite web (Archive).
  10. Sunquist, Mel and Fiona Sunquist. 2002. Wild Cats of the World. University Of Chicago Press, Chicago
  11. Sunquist, Mel and Fiona Sunquist. 2002. Wild Cats of the World. University Of Chicago Press, Chicago
  12. Template:Citeweb
  13. Template:Cite web
  14. Cracraft J., Felsenstein J., Vaughn J., Helm-Bychowski K. (1998) Sorting out tigers (Panthera tigris) Mitochondrial sequences, nuclear inserts, systematics, and conservation genetics. Animal Conservation 1: 139–150.
  15. Sunquist, Mel and Fiona Sunquist. 2002. Wild Cats of the World. University Of Chicago Press, Chicago
  16. Tiger – BangaliNET.com
  17. Tiger – Oakland Zoo
  18. Sunquist, Fiona & Mel Sunquist. 1988. Tiger Moon. The University of Chicago Press, Chicago.
  19. 19.0 19.1 Vratislav Mazak: Der Tiger. Nachdruck der 3. Auflage von 1983. Westarp Wissenschaften Hohenwarsleben, 2004 ISBN 3 894327596
  20. Sympatric Tiger and Leopard: How two big cats coexist in the same area. Ecology.info
  21. Template:Citeweb
  22. Template:Cite web
  23. Template:Cite web
  24. Template:Cite web
  25. Big Cat Recuse - Tiger
  26. Cite error: Invalid <ref> tag; no text was provided for refs named IUCN
  27. Medicare program; endangered tigers; foster children. 2007. 60 Minutes (CBS).
  28. WWF: Chinese tiger farms must be investigated
  29. WWF: Breeding tigers for trade soundly rejected at CITES
  30. Indian tiger isn't 100 per cent “swadeshi (Made in India)”; by PALLAVA BAGLA; Indian Express Newspaper; November 19, 1998
  31. Tainted Royalty, WILDLIFE: ROYAL BENGAL TIGER, A controversy arises over the purity of the Indian tiger after DNA samples show Siberian tiger genes. By Subhadra Menon. INDIA TODAY, November 17, 1997
  32. The Tale of Tara, 4: Tara's Heritage from Tiger Territory website
  33. Genetic pollution in wild Bengal tigers, Tiger Territory website
  34. Interview with Billy Arjan Singh: Dudhwa's Tiger man, October 2000, Sanctuary Asia Magazine, sanctuaryasia.com
  35. Mitochondrial DNA sequence divergence among big cats and their hybrids by Pattabhiraman Shankaranarayanan* and Lalji Singh*, *Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India, Centre for DNA Fingerprinting and Diagnostics, CCMB Campus, Uppal Road, Hyderabad 500 007, India
  36. Central Zoo Authority of India (CZA), Government of India
  37. "Indians Look At Their Big Cats' Genes", Science, Random Samples, Volume 278, Number 5339, Issue of 31 October 1997, 278: 807 (DOI: 10.1126/science.278.5339.807b) (in Random Samples),The American Association for the Advancement of Science
  38. BOOKS By & About Billy Arjan Singh
  39. Book - Tara : The Cocktail Tigress/Ram Lakhan Singh. Edited by Rahul Karmakar. Allahabad, Print World, 2000, xxxviii, 108 p., ills., $22. ISBN 81-7738-000-1. A book criticizing Billy Arjan Singh's release of hand reared hybrid Tigress Tara in the wild at Dudhwa National Park in India
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