Tigers once ranged widely across eastern Eurasia, from the Black Sea in the west, to the Indian Ocean in the south, and from Kolyma to Sumatra in the east. Over the past 100 years, they have lost 93% of their historic range, and have been extirpated from Western and Central Asia, from the islands of Java and Bali, and from large areas of Southeast, Southern, and Eastern Asia. Today, they range from the Siberian taiga to open grasslands and tropical mangrove swamps. The remaining six tiger subspecies have been classified as endangered by the International Union for Conservation of Nature (IUCN). The global population in the wild is estimated to number between 3,062 and 3,948 individuals, down from around 100,000 at the start of the 20th century, with most remaining populations occurring in small pockets isolated from each other, of which about 2,000 exist on the Indian subcontinent.