The Sunda Island tiger, or the Sumatran tiger, is the smallest tiger subspecies in the world, weighing up to 140kg. For reference, the tigers that live in the Amur region are the biggest of all the big cats where males can weigh up to twice as much as Sunda Island tigers. They are also very rare -  there are estimated to be around 600 in the wild, and are only found on the Indonesian island of Sumatra.  Since the 1980s, the human population of south-east Asia has nearly doubled from 357 million to around 668 million in 2020. And this has had an impact on tiger numbers, which have been shrinking along with their habitats. As human settlements expand in the region, Sunda Island tigers are increasingly likely to encounter people, which could lead to a further rise in human-tiger conflict. Tiger poaching and illegal trading of tiger parts and products are also of serious concern to their survival.