Poachers, pollution and forest devastation are threatening many wild bears with extinction, according to a report by the World Wide Fund for Nature.

There are wild bears living in 62 countries today, and all are under threat to some degree.

Only polar bears are still found across their original range - but even they could be harmed by pollutants in the Arctic and the melting of the pack ice due to global warming.

Polar bears: Under threat from global warming

In China, demand is high for bear bile - a product of the gall bladder used in traditional medicines.

And in Russia, home to the world's biggest brown bear population, poachers are targeting bears for their hides and gall bladders.

Elizabeth Kemf, one of the report's authors, says bears in the Americas are also under threat from traders for their body parts and for food.

In South America particularly, forests are being razed to make way for cattle ranches and drug crops, and bears are popular with hunters for their bile and meat.

In the Asian region, forest fires have killed many sun bears, while logging has further reduced their habitat.

The report adds that bears in India and Bangladesh are also unlikely to survive for more than a few decades.

But the worst situation is in Europe, where the last remaining bears - mostly living in Italy, Austria and France - are doomed to extinction unless drastic steps to save them are taken soon.