Tuesday, March 23, 2010

Tiger

Tigers - the real kings of more than jungles



"The tiger is the symbol of power, unbridled, elemental�. And he lives alone, unblemished, unmarred. The more you know about him, the more he gets into your imagination."

The tiger (Panthera tigris) is a member of the Felidae family, the largest of the four "big cats" in the genus Panthera. Native to much of eastern and southern Asia, the tiger is an apex predator and an obligate carnivore. Reaching up to 3.3 metres (11 ft) in total length and weighing up to 300 kilograms (660 pounds), the larger tiger subspecies are comparable in size to the biggest extinct fields. Aside from their great bulk and power, their most recognizable 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 subspecies is the Siberian tiger.

Highly adaptable, tigers range from the Siberian taiga, to open grasslands, to 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 endemic to some of the more densely populated places on earth, has caused significant conflicts with humans. Of the nine subspecies of modern tiger, three are extinct and the remaining six are classified as endangered, some critically so. The primary direct causes are habitat destruction and fragmentation, and hunting. Their historical range once stretched from Mesopotamia and the Caucasus through most of South and East Asia. Today it has been radically reduced. While all surviving species are under formal protection, poaching, habitat destruction and inbreeding depression continue to threaten the species.

Subspecies

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:

A Bengal tigress with her cub.
  • 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.
Scientific Name: Panthera tigris tigris
Range: Bangladesh, Bhutan, India, Myanmar, Nepal
Average Weight:
Female: 221 - 353 Pounds
Male: 419 - 569 Pounds
Average Length:
Female: 7 Feet 11 Inches - 8 Feet 7 Inches
Male: 8 Feet 8 Inches - 10 Feet 2 Inches
Prey: Antelope, Buffalo, Cattle, Deer, Pigs.
Gestation period: Approximately 103 days
Cubs per litter: 1-5
Average: 2-3
Cub Maturity:
After 8 Weeks: join mother when hunting
Approximately 6 Months: learned how to kill
11/4 - 11/2 Years: can hunt for themselves
Status:
1998 Approximates 3,176 - 4,556
1997 Approximates 3,000 - 4,700
Other Information:
1) Also known as the Royal Bengal Tiger.
2) Also known as the Indian Tiger.
3) All white tigers are Bengals. All white Bengals in captivity in the USA originated from one white male bengal captured in India in 1951 and inbred with his offspring. Only Bengal tigers have the double recessive gene that causes the white coloring. White tigers are not albino.
4) There are more Bengal tigers than all 4 of the other remaining tiger subspecies added together


Indochinese tiger
  • 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.
Scientific Name: Panthera tigris corbetti
Range: Cambodia, Lao PDR, Malaysia, Myanmar, Thailand, Vietnam
Average Weight:
Female: 221 - 287 Pounds
Male: 330 - 430 Pounds
Average Length:
Female: 7 Feet 7 Inches - 8 Feet 8 Inches
Male: 8 Feet 5 Inches - 9 Feet 4 Inches
Prey: Cattle, Deer, Pigs.
Gestation period: Approximately 103 days
Cubs per litter: 1-5
Average: 2-3
Cub Maturity:
After 8 Weeks: join mother when hunting
Approximately 6 Months: learned how to kill
11/4 - 11/2 Years: can hunt for themselves
Status:
1998 Approximates 1,227 - 1,785
1997 Approximates 1,150 - 1,750


Malayan tiger
  • 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, 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.


Sumatran tiger
  • 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.
Scientific Name: Panthera tigris sumatrae
Range: Indonesian Island of Sumatra
Average Weight:
Female: 165 - 243 Pounds
Male: 221 - 309 Pounds
Average Length:
Female: 7 Feet 1 Inches - 7 Feet 7 Inches
Male: 7 Feet 3 Inches - 8 Feet 8 Inches
Prey: Cattle, Deer, Pigs.
Gestation period: Approximately 103 days
Cubs per litter: 1-5
Average: 2-3
Cub Maturity:
After 8 Weeks: join mother when hunting
Approximately 6 Months: learned how to kill
11/4 - 11/2 Years: can hunt for themselves
Status:
1998 Approximates 400 - 500
1997 Approximates 400 - 735



Siberian tiger
  • The Siberian tiger (Panthera tigris altaica), also known as the Amur, Manchurian, Altaic, Korean or North China tiger, is confined to the Amur-Ussuri region of Primorsky Krai and Khabarovsk Krai in far eastern Siberia, where it is now protected. Considered the largest subspecies, it had 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.
Scientific Name: Panthera tigris altaica
Range: Mainly eastern Russia; Some in northeastern
China and northern North Korea
Average Weight:
Female: 221 - 368 Pounds
Male: 419 - 675 Pounds
Average Length:
Female: 7 Feet 11 Inches - 9 Feet
Male: 8 Feet 8 Inches - 10 Feet 9 Inches
Prey: Cattle, Deer, Pigs.
Gestation period: Approximately 103 days
Cubs per litter: 1-5
Average: 2-3
Cub Maturity:
After 8 Weeks: join mother when hunting
Approximately 6 Months: learned how to kill
11/4 - 11/2 Years: can hunt for themselves
Status:
1998 Approximates 360 - 406
1997 Approximates 436 - 505
Other Information:
1) Also known as the Amur Tiger.
2) Also known as the Ussuri Tiger.
3) Also known as the Manchurian Tiger.
4) Also known as the Northeast China Tiger.
5) Largest of the tiger subspecies.



South China tiger
  • 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.[33][clarification needed] 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 photoshopped, and the “sighting” turned into a massive scandal.
Scientific Name: Panthera tigris amoyensis
Range: Central and eastern China
Average Weight:
Female: 221 - 254 Pounds
Male: 287 - 386 Pounds
Average Length:
Female: 7 Feet 3 Inches - 7 Feet 11 Inches
Male: 7 Feet 7 Inches - 8 Feet 7 Inches
Prey: Cattle, Deer, Pigs.
Gestation period: Approximately 103 days
Cubs per litter: 1-5
Average: 2-3
Cub Maturity:
After 8 Weeks: join mother when hunting
Approximately 6 Months: learned how to kill
11/4 - 11/2 Years: can hunt for themselves
Status:
1998 Approximates 20 - 30
1997 Approximates 20 - 78
Other Information:
1) Also known as the Amoy Tiger.
2) Also known as the Chinese Tiger.
3) Most endangered of the tiger subspecies.
4) Considered to be the evolutionary ancestor of all tigers.
5) The only zoo's that have this tiger are in China.

Extinct subspecies

A hunted down Balinese tiger
  • The Bali Tiger (Panthera tigris balica) was limited to the island of Bali. They were the smallest of all tiger subspecies, with a weight of 90–100 kg in males and 65–80 kg in females. 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 Hinduism.
Scientific Name: Panthera tigris balica
Range: Island of Bali
Average Weight:
Female: 143 - 176 Pounds
Male: 198 - 221 Pounds
Average Length:
Female: 6 Feet 3 Inches - 6 Feet 11 Inches
Male: 7 Feet 3 Inches - 7 Feet 7 Inches
Prey: No Data
Gestation period: No Data
Cubs per litter: No Data
Average: No Data
Cub Maturity: No Data
Status: Extinct since the late 1930's or early 1940's
Other Information:
1) Smallest of all 8 tiger subspecies.



A photograph of a Javan tiger.
  • 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 confirmed specimen was sighted in 1979, but there were a few reported sightings during the 1990s. With a weight of 100–141 kg for males and 75–115 kg for females, the Javan tiger was one of the smaller subspecies, approximately the same size as the Sumatran tiger.
Scientific Name: Panthera tigris sondaica
Range: Island of Java
Average Weight:
Female: 165 - 254 Pounds
Male: 221 - 311 Pounds
Average Length:
Female: No Data
Male: 8 Feet 1 Inch
Prey: No Data
Gestation period: No Data
Cubs per litter: No Data
Average: No Data
Cub Maturity: No Data
Status: Extinct since the late 1970's or early 1980's



A captive Caspian Tiger, Berlin Zoo 1899

Caspian Tiger (formerly Panthera tigris virgata), also known as the Persian tiger or Turanian tiger was the westernmost population of Siberian tiger, found in Iran, Iraq, Afghanistan, Turkey, Mongolia, Kazakhstan, the Caucasus, Tajikistan, Turkmenistan, and Uzbekistan until it apparently became extinct in the late 1950s, though there have been several alleged more recent sightings of the tiger.Though originally thought to have been a distinct subspecies, genetic research in 2009 suggest that the animal was largely identical to the Siberian tiger.

Scientific Name: Panthera tigris virgata
Range: Afghanistan, Iran, Turkey, Mongolia, and the Central Asiatic area of Russia
Average Weight:
Female: 187 - 298 Pounds
Male: 374 - 529 Pounds
Average Length:
Female: 7 Feet 11 Inches - 8 Feet 6 Inches
Male: 8 Feet 8 Inches - 9 Feet 8 Inches
Prey: No Data
Gestation period: No Data
Cubs per litter: No Data
Average: No Data
Cub Maturity: No Data
Status: Extinct since the 1950's


Hybrids

Lions have been known to breed with tigers (most often the Amur and Bengal subspecies) to create hybrids called ligers and tigons.

The liger is a cross between a male lion and a tigress. Because the lion sire passes on a growth-promoting gene, but the corresponding growth-inhibiting gene from the female tiger is absent, ligers grow far larger than either parent. They share physical and behavioural qualities of both parent species (spots and stripes on a sandy background). Male ligers are sterile, but female ligers are often fertile. Males have about a 50% chance of having a mane, but, even if they do, their manes will be only around half the size of that of a pure lion. Ligers are typically between 10 to 12 feet in length, and can be between 800 and 1,000 pounds or more.

The less common tigon is a cross between the lioness and the male tiger.


Colour variations

White tigers

A pair of white Bengal tigers at the Singapore Zoo.

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 and pink noses.

Golden tabby tigers

A rare golden tabby/strawberry tiger at the Buffalo Zoo.

In addition, another recessive gene may create a very unusual "golden tabby" colour variation, sometimes known as "strawberry." Golden tabby tigers have light gold fur, pale legs and faint orange stripes. Their fur tends to be much thicker than normal. There are extremely few golden tabby tigers in captivity, around 30 in all. Like white tigers, strawberry tigers are invariably at least part Bengal. Some golden tabby tigers, called heterozygous tigers, carry the white tiger gene, and when two such tigers are mated, can produce some stripeless white offspring. Both white and golden tabby tigers tend to be larger than average Bengal tigers.

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