keoladeo national park in Bharatpur, Rajasthan, is fast losing its population of rare birds due to unchecked human habitation. The human population around the forest has registered a 24 per cent growth over the last 10 years. This is threatening bird migration, says a study conducted by the United Nations Population Fund representative in India, Michael Vlassoff and environmentalist K S Subramanian. Known as a birds' paradise, the 15,000 sq km park attracts more than 375 types of avian species, including Siberian cranes. The increased population pressure was especially evident in 29 sq km area of the park where several endangered species of birds migrate every year.