London railway chiefs warn of dangers of children falling on tracks

Thai zoo celebrates successful breeding of 'vulnerable' Asian black bear in captivity

Vulnerable Visayan leopard cat caught in snare rescued in the Philippines

Tourist saves 'vulnerable' Olive Ridley sea turtle tangled in fishing net in Costa Rica

Open wide! Hippos spread their jaws for visitors to feed them lunch

Three giant panda boars fight for female panda's heart in Chinese nature reserve