WWF "African Elephants" three to five million mentions vulnerable World Wildlife Fund African Elephants (WWF) WWF African elephants | WWF fact sheets "African Elephants" "Endangered species" WWF Africa "Endangered species" 20 percent WWF World Wildlife Fund estimates World Wildlife Fund estimates African elephants | WWF might become extinct "African Elephants" "African Elephants" "Endangered species" estimates around four million to around 300,000 "African Elephants" estimates