AP: Conservationists must protect tiger populations in a few concentrated breeding grounds in Asia instead of trying to safeguard vast, surrounding landscapes, if they want to save the big cats from extinction, scientists said Tuesday. Only about 3,500 tigers are left in the wild worldwide, less than one third of them breeding females, according to one of the authors of a new study, John Robinson of the Wildlife Conservation Society. Much has been done to try to save the world’s …