What it is
The Sumatran tiger is the only surviving island subspecies of Panthera tigris. IUCN assesses the tiger species as Endangered (2022) and has long treated P. t. sumatrae as Critically Endangered. Published island-wide figures disagree; conservation groups often work with a band of a few hundred (commonly cited around 400-600). There is no single agreed census. Javan and Balinese tigers are already extinct.
Range
Remaining forest blocks of Sumatra, especially landscape-scale parks such as Leuser, Kerinci Seblat, and Bukit Barisan Selatan. Gone from much of the lowland.
What happened
Oil palm, pulp, roads, snares, and the trade in skins and bones isolated the last breeding groups. Prey is thin where forest is a patchwork. This is a different animal from the Amur tiger already on this shelf.
When / status
Critically Endangered as a subspecies now.
Human role
Forest conversion and poaching on an island with no other tiger left.
Sources
IUCN Red List (Panthera tigris, EN, 2022; subspecies sumatrae CR in specialist assessments); WCS Indonesia landscape work.