Tigers once ranged widely across 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). Major reasons for population decline include habitat destruction, habitat fragmentation and poaching.