Showing posts with label Bengal tiger. Show all posts
Showing posts with label Bengal tiger. Show all posts

Monday, February 22, 2010

Evolution: White Tiger

Photo: sleeping white tiger at the Audubon Zoo in New Orleans, Louisiana (April, 2003).

White tigers are neither albino, nor do they constitute a separate subspecies and they can breed with orange or brown ones, although approximately half of the resulting offspring will be heterozygous for the recessive white gene and their fur will be orange. But if the orange parent was itself already a heterozygous tiger, which would give each cub a 50 per cent chance of being either double recessive white or heterozygous orange. If two heterozygous tigers or heterozygote breed, on average, 25 per cent of their offspring will be white, 50 per cent will be heterozygous orange (with white genes) and 25 per cent will be homozygous orange (with no white genes).

In the 1970s a pair of heterozygous orange tigers produced 13 cubs in Alipore Zoo, India, out of which 3 were white tiger cubs. If two white tigers breed 100 per cent of their cubs will be homozygous white tigers. A tiger which is homozygous for the white gene may also be heterozygous or homozygous for many different genes. The question whether a tiger is heterozygous (a heterozygote) or homozygous (a homozygote) depends on which gene is being discussed. Inbreeding promotes homozygosis and this fact has been used as a strategy to breed white tigers in captivity.

From the casual way that Jim Corbett makes reference to a white tigress, which he filmed with two orange cubs, in his ‘Man-Eaters of Kumaon’ (1946), it is suggested that white tigers were nothing out of the ordinary to him. Corbett's black and white film footage is probably the only film in existence of a white tiger in the wild. It illustrates again that white tigers survived and reproduced in the wild. The film was used in a National Geographic documentary ‘Man-eaters of India’ (1984), about Corbett's life, based on his 1957 book by the same title.

White tigers with dark stripes were recorded as living in the wild in India during the Mughal Empire (1556-1605). A painting from 1590 of Akbar while hunting near Gwalior depicts four tigers, two of which appear white.

The Journal of The Bombay Natural History Society reported 17 white tigers shot between 1907 and 1933: in several separate locations in Orissa, Bilaspur, Sohagpur and Rewa.

On January 22, 1939, the Prime Minister of Nepal shot a white tiger at Barda camp in Terai, Nepal. The last observed wild white tiger was shot in 1958, and the mutation is believed to be extinct in the wild.

Arthur Locke mentions white tigers in ‘The Tigers Of Trengganu’ (1954).

E.P. Gee collected accounts of 35 white tigers from the wild up to 1959, with still more uncounted from Assam where he had his tea plantation. Some white tigers in the wild had reddish stripes known as ‘red tigers’. The Boga-bagh, or ‘white tiger’, Tea Estate in upper Assam, was named that after two white tigers that were shot there in the early 1900s.

In India, the Rewa hunters' diaries recorded 9 white tigers in the fifty years prior to 1960.

One theory of white tigers holds that they were symptomatic of inbreeding as a consequence of over hunting and habitat loss, as tiger populations became isolated.

White Tiger in Miami Metrozoo


Miami Metrozoo -White Tiger, originally uploaded by b-a-boop.

Watch this white tiger found in captivity, in Miami MetroZoo, spread over 740 acres (3.0 squire km), is the largest and oldest zoological garden in Florida. It is located in southern unincorporated Miami-Dade County southwest of the city of Miami and west of the village of Palmetto Bay. It houses over 1,200 wild animals and is the only subtropical zoo in the continental United States.

Monday, September 28, 2009

Bengal Tiger in Kerala


tiger, originally uploaded by Sreejith Kodoth.

The author who loves wildlife photography, clicked this photo when he was working with Kerala Government's Forest Department.

Wednesday, July 29, 2009

Tigers vanish from Indian tiger reserves

Panthera tigris tigris - Royal Bengal tiger
Tiger and tiger cub in Pilibhit Tiger Reserve
Tiger reserves in India - Map of India

There are 37 tiger reserves in India. But two of the tiger reserves, Panna in MP and Sariska in Rajasthan have visibly no tigers now. There is no reliable information available on the number of tigers in seven other tiger reserves. These seven tiger reserves also will go into the list of tiger reserves without tigers if immediate steps are not taken. This information came out at the All India Meet for Tiger Reserve Directors in Sariska.

Speaking at an interactive session on the fate of Indian Royal Bengal tiger, Indian Minister of State for Environment and Forests Jairam Ramesh asserted on July 28 that innumerable instances of poaching of wild animals, particularly the majestic striped felines like the tiger, pose a serious threat to India’s entire ecosystem. He said instead of trans-locating the tigers, poaching needs to be curbed.

"Between the years 2002 to 2004 around 23 tigers were poached in Sariska National Park. At present we have trans-located three tigers from Ranthambhore. But trans-location is not the solution. We have to fight against poaching. Today poaching is the biggest threat," Jairam Ramesh said.

National Tiger Conservation Authority (NTCA) Member Secretary Rajesh Gopal admitted that one of the tiger reserves, Indravati in Chhattisgarh, where “tiger protection efforts in the past 20 years have failed”, should be denotified.

The other tiger reserves facing the extinction of tigers are Simlipal in Orissa, Palamau in Jharkhand, Manas in Assam, Namdapha in Arunachal Pradesh, Dampa in Mizoram, Buxa in West Bengal and Valmiki in Bihar.

The Royal Bengal tiger (scientific nomenclature: Panthera tigris tigris or Panthera tigris bengalensis), is the most populous subspecies of tiger mainly found in India and Bangladesh, in addition to parts of Nepal, Bhutan and Myanmar.

There were 40,000 tigers in India at the beginning of the last century. In 2006, when the last tiger count was made, about 1411 wild tigers were reported by the Government of India's National Tiger Conservation Authority. Since then about 100 tigers have died because of poaching, natural reasons and man-animal conflicts.

In the last few months not even one of the 12 tigers believed to be in Buxa in Jaipalguri district (West Bengal) was spotted.

Manas had 40 tigers in 2006 but the tiger population is dwindling due to deforestation and poaching. Four tiger deaths were reported in 2009 from Manas.

Valmiki in Bihar had 10 tigers in 2006. This year poachers from Nepal have been very active in the reserve that has seen very poor conservation efforts.

Simlipal in Orissa had 40 tigers in 2006, but in 2008-09 it was reduced to two tigers per 100 sq km from the ideal two tigers per 10 sq km; poachers have been caught on camera killing prey.

Indravati in Chhattisgarh has made no estimate of tiger population in the last nine years. In 2000, the reserve had 100 tigers. But now doubts are being expressed about possible killing of a substantial numbers of tigers by Naxalites to raise funds.

Palamau in Jharkhand had no census of tigers in 2006. Poaching is rampant in the vicinity of the tiger reserve.

Namdapha in Arunachal Pradesh had 12 tigers in 2006, but no tiger was spotted in the past 12 months.

The above is part of the impressive statistics presented at the All India Meet for Tiger Reserve Directors. There are reports about India facing difficulties in controlling illicit trade in tiger organs, tiger bones, tiger skin and products and this has been brought to the notice of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) time and again, according to reports.

India is the home to about 50% of the world's tiger population. The Bengal tiger is the second largest subspecies after the Siberian tiger. The tiger species Panthera tigris is the national animal of India. The tiger subspecies Panthera tigris tigris is the national animal of Bangladesh.