The tiger (Panthera tigris), a member of the Felidae family, is the largest of the four “big cats” in the genus Panthera. The tiger is native to much of eastern and southern Asia, and is an apex predator and an obligate carnivore. The larger tiger subspecies are comparable in size to the biggest extinct felids, reaching up to 3.3 metres (11 ft) in total length, weighing up to 300 kilograms (660 pounds), and having canines up to 4 inches long. Aside from their great bulk and power, their most recognisable feature is a pattern of dark vertical stripes that overlays near-white to reddish-orange fur, with lighter underparts. The most numerous tiger subspecies is the Bengal tiger, while the largest is the Siberian tiger.
Tigers have a lifespan of 10–15 years in the wild, but can live longer than 20 years in captivity. They are highly adaptable and range from the Siberian taiga to open grasslands and tropical mangrove swamps.
They are territorial and generally solitary animals, often requiring large contiguous areas of habitat that support their prey demands. This, coupled with the fact that they are indigenous to some of the more densely populated places on earth, has caused significant conflicts with humans. Three of the nine subspecies of modern tiger have gone extinct, and the remaining six are classified as endangered, some critically so. The primary direct causes are habitat destruction, fragmentation, and hunting.
Historically, tigers have existed from Mesopotamia and the Caucasus throughout most of South and East Asia. Today, the range of the species is radically reduced. All surviving species are under formal protection, yet poaching, habitat destruction, and inbreeding depression continue to threaten the tigers.
Tigers are among the most recognisable and popular of the world’s charismatic megafauna. They have featured prominently in ancient mythology and folklore, and continue to be depicted in modern films and literature. Tigers appear on many flags and coats of arms, as mascots for sporting teams, and as the national animal of several Asian nations, including India.
In the past, tigers were found throughout Asia, from the Caucasus and the Caspian Sea to Siberia and Indonesia. Today the range of the tiger is only 7% of what it used to be. Furthermore, within the past decade alone, the estimated area known to be occupied by tigers has declined by 41%.
During the 19th century, the tiger completely vanished from western Asia and became restricted to isolated pockets in the remaining parts of their range. Today, their range is fragmented, and certain parts degraded, and extends from India in the west to China and Southeast Asia in the east. The northern limit is close to the Amur River in south eastern Siberia. The only large island inhabited by tigers today is Sumatra. Tigers vanished from Java and Bali during the 20th century. In Borneo they are known only from fossil remains.
Tiger habitats will usually include sufficient cover, proximity to water, and an abundance of prey. Bengal Tigers live in many types of forests, including wet; evergreen; the semi-evergreen of Assam and eastern Bengal; the mangrove forest of the Ganges Delta; the deciduous forest of Nepal, and the thorn forests of the Western Ghats. Compared to the lion, the tiger prefers denser vegetation, for which its camouflage colouring is ideally suited, and where a single predator is not at a disadvantage compared with the multiple felines in a pride.
Among the big cats, only the tiger and jaguar are strong swimmers; tigers are often found bathing in ponds, lakes, and rivers. During the extreme heat of the day, they often cool off in pools. Tigers are excellent swimmers, and are able to carry prey through the water.
There are nine recent subspecies of tiger, three of which are extinct. Their historical range (severely diminished today) ran through Bangladesh, Siberia, Iran, Afghanistan, India, China, and southeast Asia, including some Indonesian islands. The surviving subspecies, in descending order of wild population, are:
The Bengal tiger or the Royal Bengal tiger (Panthera tigris tigris) is the most common subspecies of tiger and is found primarily in India and Bangladesh. It lives in varied habitats: grasslands, subtropical and tropical rainforests, scrub forests, wet and dry deciduous forests, and mangroves. Males in the wild usually weigh 205 to 227 kg (450 to 500 lb), while the average female will weigh about 141 kg. However, the northern Indian and the Nepalese Bengal tigers are somewhat bulkier than those found in the south of the Indian Subcontinent, with males averaging around 235 kilograms (520 lb). While conservationists already believed the population to be below 2,000, the most recent audit by the Indian Government’s National Tiger Conservation Authority has estimated the number at just 1,411 wild tigers (1165–1657 allowing for statistical error), a drop of 60% in the past decade. Since 1972, there has been a massive wildlife conservation project, known as Project Tiger, to protect the Bengal tiger. Despite increased efforts by Indian officials, poaching remains rampant and at least one Tiger Reserve (Sariska Tiger Reserve) has lost its entire tiger population to poaching. The passing of the Forest Rights Act by the Indian government in 2006 has worsened the situation as evidence has shown that human habitats and tigers cannot co-exist and has pushed the Indian tiger on the brink of extinction. However, another census by the government in 2011 using better counting methods showed a rise of 20%, taking the numbers to 1,706.

The Indochinese Tiger (Panthera tigris corbetti), also called Corbett’s tiger, is found in Cambodia, China, Laos, Burma, Thailand, and Vietnam. These tigers are smaller and darker than Bengal tigers: Males weigh from 150–190 kg (330–420 lb) while females are smaller at 110–140 kg (240–310 lb). Their preferred habitat is forests in mountainous or hilly regions. Estimates of the Indochinese tiger population vary between 1,200 to 1,800, with only several hundred left in the wild. All existing populations are at extreme risk from poaching, prey depletion as a result of poaching of primary prey species such as deer and wild pigs, habitat fragmentation and inbreeding. In Vietnam, almost three-quarters of the tigers killed provide stock for Chinese pharmacies.

The Malayan Tiger (Panthera tigris jacksoni), exclusively found in the southern 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,[36] 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 the smallest of the mainland tiger subspecies, and the second smallest living subspecies, with males averaging about 120 kg and females about 100 kg in weight. 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, and is critically endangered. It is the smallest of all living tiger subspecies, with adult males weighing between 100–140 kg (220–310 lb) and females 75–110 kg (170–240 lb). Their small size is an adaptation to the thick, dense forests of the island of Sumatra where they reside, as well as the smaller-sized prey. 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 does not go extinct. This has led to suggestions that Sumatran tigers should have greater priority for conservation than any other subspecies. While habitat destruction is the main threat to existing tiger population (logging continues even in the supposedly protected national parks), 66 tigers were recorded as being shot and killed between 1998 and 2000, or nearly 20% of the total population.

The Siberian tiger (Panthera tigris altaica), also known as the Amur, Manchurian, Altaic, Korean or North China tiger, which is the most northernmost subspecies, is confined to the Amur-Ussuri region of Primorsky Krai and Khabarovsk Krai in far eastern Siberia, where it is now protected. The largest subspecies of tiger, it has a head and body length of 160–180 cm for females and 190–230+ cm for males, plus a tail of about 60–110 cm long (about 270–330 cm in total length) and an average weight of around 227 kilograms (500 lb) for males, the Amur tiger is also noted for its thick coat, distinguished by a paler golden hue and fewer stripes. The heaviest wild Siberian tiger on record weighed in at 384 kg, but according to Mazak these giants are not confirmed via reliable references. Even so, a six-month old Siberian tiger can be as big as a fully grown leopard. 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. Genetic research in 2009 demonstrated that the Siberian tiger, and the western “Caspian tiger” (once thought to have been a separate subspecies that became extinct in the wild in the late 1950s) are actually the same subspecies, since the separation of the two populations may have occurred as recently as the past century due to human intervention.

The South China Tiger (Panthera tigris amoyensis), also known as the Amoy or Xiamen tiger, is the most critically endangered subspecies of tiger and is listed as one of the 10 most endangered animals in the world. One of the smaller tiger subspecies, the length of the South China tiger ranges from 2.2–2.6 m (87–100 in) for both males and females. Males weigh between 127 and 177 kg (280 and 390 lb) while females weigh between 100 and 118 kg (220 and 260 lb). From 1983 to 2007, no South China tigers were sighted. In 2007 a farmer spotted a tiger and handed in photographs to the authorities as proof. The photographs in question, however, were later exposed as fake, copied from a Chinese calendar and digitally altered, and the “sighting” turned into a massive scandal.
In 1977, the Chinese government passed a law banning the killing of wild tigers, but this may have been too late to save the subspecies, since it is possibly already extinct in the wild. 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. Currently, there are breeding efforts to reintroduce these tigers to the wild.

White tigers – There is a well-known mutation that produces the white tiger, technically known as chinchilla albinistic, an animal which is rare in the wild, but widely bred in zoos due to its popularity. Breeding of white tigers will often lead to inbreeding (as the trait is recessive). Many initiatives have taken place in white and orange tiger mating in an attempt to remedy the issue, often mixing subspecies in the process. Such inbreeding has led to white tigers having a greater likelihood of being born with physical defects, such as cleft palates and scoliosis (curvature of the spine). Furthermore, white tigers are prone to having crossed eyes (a condition known as strabismus). Even apparently healthy white tigers generally do not live as long as their orange counterparts. Recordings of white tigers were first made in the early 19th century. They can only occur when both parents carry the rare gene found in white tigers; this gene has been calculated to occur in only one in every 10,000 births. The white tiger is not a separate sub-species, but only a colour variation; since the only white tigers that have been observed in the wild have been Bengal tigers (and all white tigers in captivity are at least part Bengal), it is commonly thought that the recessive gene that causes the white colouring is probably carried only by Bengal tigers, although the reasons for this are not known.Nor are they in any way more endangered than tigers are generally, this being a common misconception. Another misconception is that white tigers are albinos, despite the fact that pigment is evident in the white tiger’s stripes. They are distinct not only because of their white hue; they also have blue eyes.

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