Of the eight original subspecies of tigers, three have become extinct in the last 60 years, an average of one every 20 years.The Bali tiger became extinct in the 1930's. The Caspian tiger was forced into extinction in the 1970's. And the Javan tiger followed in the 1980's.

The number of tigers in the 1900's --over 100,000 -- dropped to 4,000 in the 1970's. Today, they are a critically endangered species with the total of all the wild populations of the five remaining subspecies (Bengal tigers, IndoChinese tigers, Siberian tigers, South China tigers, and Sumatran tigers) is an estimated 4,600 and 7,700 tigers.
It is known that all remaining tigers live in small, isolated populations in widely scattered reserves.

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Bengal Tigers

The Bengal tiger, or Royal Bengal tiger, roams a wide range of habitats including high altitudes, tropical and subtropical rainforests, mangroves, and grasslands. They are primarily found in parts of India, Nepal, Bhutan, Bangladesh and Myanmar.
All white tigers are a variation in color of the Bengal tiger, some tigers have been reported that are white with or without black stripes.

IndoChinese Tigers

It is estimated fewer than 1,500 Indochinese tigers are left in the wild. However since the tiger has a very wide range, it makes it difficult for researchers to determine the exact numbers. Therefore some scientists believe the numbers may be a few as 1,200.

Siberian tigers

It is estimated the wild population of Siberian tigers at around 350-450 tigers.

Almost all wild Siberian tigers live the Southeast corner of Russia in the Sikhote-Alin mountain range east of the Amur River. Their former range included northeastern China and the Korean Peninsula, and as far west as Mongolia. They are the largest of the tiger species and can grow up to 13 feet in length and weigh up to 700 lbs.

South China tigers

The South China tiger is the smallest of all the tiger subspecies, and it is the most critically endangered. Little is know about their exact numbers in the wild, but some estimates would put the number at under 20 tigers. Others would say that estimate is high.

The reality is that no South China tiger has been seen in the wild for the last 20 years.

Sumatra Tiger

It is estimated that only between 500-600 Sumatran tigers remain in the wild, and the actual number may be as low as 400. And their population is dwindling rapidly.
The Sumatran tiger is considered to be a ‘critically’ endangered species.

The Sumatran tiger is found only on the Indonesian island of Sumatra off the Malaysian Peninsula. Their habitat ranges from lowland forest to mountain forest and includes evergreen, swamp and tropical rain forests.