Amur tigers on 'genetic brink'
By Matt Walker, Editor, Earth News The world’s largest cat is down to an effective wild population of fewer than 35 individuals, new research has found. Although up to 500 of the big cats actually survive in the wild, the effective population is a measure of their genetic diversity. That in turn is a good predictor of the Amur tiger’s chances of survival. The results come from the most complete genetic survey yet of wild Amur tigers, the rarest subspecies of tiger. At the start of the 20th Century, nine subspecies of tiger existed, with a total world population of more than 100,000 individuals. Human impacts have since caused the extinction of three subspecies, the Javan tiger, Bali tiger and Caspian tiger, and world tiger numbers could now have fallen to fewer than 3000. … During the early 20th century, the Amur tiger too was almost driven to extinction, as expanding human settlements, habitat loss and poaching wiped out this biggest of cats from over 90% of its range. By the 1940s just 20 to 30 individuals survived in the wild. Since then, a ban on hunting and a remarkable conservation effort have slowly helped the Amur tiger recover. Today, up to 500 are thought to survive in the wild, while 421 cats are kept in captivity. However, the genetic health of the tiger hasn’t improved, according to a new analysis published in Molecular Ecology. …
