Wild Tiger Health Project
Created by Dr John C M Lewis

An invaluable source of detailed information on tiger range, status and habitat can be found on the IUCN Red List of Threatened Species (www.iucnredlist.org). (See Goodrich et al 2015). Much of the review given in this section has been informed by this and other recent sources (eg Hunter 2015, Tilson & Nyhus 2010). 

Historically the tiger (Panthera tigris) occurred throughout central, eastern and southern Asia, but today they are found mainly in the forests of tropical Asia. The loss of more than 93% of its range over the past 100 years has led to the current situation in which the species survives only in scattered populations in < 13 countries. Breeding probably only occurs in eight of these (Bangladesh, Bhutan, India, Sumatra/Indonesia, Malaysia, Nepal, Thailand and Russia). Tigers are likely extinct or limited to a few individuals with no recent evidence of breeding in Cambodia, Laos and Vietnam. It is extinct in China except for a small number in a transboundary population with Russia. One hundred years ago tigers are thought to have numbered ~ 100,000 individuals. Today, estimates are in the order of 3,900.

The current distribution of tigers is extremely patchy:

• In South Asia tigers occur mainly in protected areas in south-western, central and north-eastern India; in a narrow band along the southern slopes and lowlands of the Himalayas (from Uttarakhand India, through Nepal and Bhutan to Arunachal India); and a population in the Sundarbans mangrove swamps of Bangladesh and India.
• In mainland Southeast Asia populations of the Indochinese subspecies remain mainly in western Thailand bordering Burma and in Peninsular Malaysia. In Burma, a few tigers persist along the Thai border, but it is unknown if these represent resident breeding populations or transients from western Thailand.
• In Sumatra tigers occur in fragmented populations along the Barisan mountain range running the length of the island and in patches of central Sumatra.
• The largest contiguous tiger population is in the Russian Far East and extending into adjacent areas of north-eastern China. Most of this population occurs outside protected areas. 

Conventionally, nine subspecies are recognised. 

The Caspian, Javan and Bali tigers are now extinct. The remaining six living subspecies (Liu et al 2018) are:

Although not widely accepted in conservation circles, a recent review of tiger taxonomy by the IUCN SSC Cat Specialist Group (Kitchener et al, 2017), has suggested that only two subspecies of tiger should be recognised:

Tigers are recognised by the IUCN as Endangered throughout their range, and commercial international trade in tigers is prohibited under the Convention for International Trade in Endangered Species (CITES) in which they are included on Appendix 1.

The major current threats to the species’ survival are:

• Unsustainable poaching to meet an illegal trade in body parts for the Oriental medicine market.
• Loss and fragmentation of habitat as a result of rapid development and a rising human population.
• Commercial logging, destruction of forest for agriculture, and expanding human settlement.
• Loss of ungulate prey through human hunting and competition from domestic livestock.
• Tiger attacks on livestock and people leading to local community intolerance, retaliatory killings and government-sanctioned removal of problem individuals

Tiger distribution map:

© The IUCN Red List of Threatened Species: Panthera tigris – published in 2015. http://dx.doi.org/10.2305/IUCN.UK.2015-2.RLTS.T15955A50659951.en