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Hyderabad's lakes and the sloping terrain of its low-lying hills provide habitat for an assortment of flora and fauna. The forest region in and around the city encompasses areas of ecological and biological importance, which are preserved in the form of national parks, zoos, mini-zoos and a wildlife sanctuary. Nehru Zoological Park, the city's one large zoo, is the first in India to have a lion and tiger safari park. Hyderabad has three national parks (Mrugavani National Park, Mahavir Harina Vanasthali National Park and Kasu Brahmananda Reddy National Park), and the Manjira Wildlife Sanctuary is about 50 km (31 mi) from the city. Hyderabad's other environmental reserves are: Kotla Vijayabhaskara Reddy Botanical Gardens, Shamirpet Lake, Hussain Sagar, Fox Sagar Lake, Mir Alam Tank and Patancheru Lake, which is home to regional birds and attracts seasonal migratory birds from different parts of the world. Organisations engaged in environmental and wildlife preservation include the Telangana Forest Department, Indian Council of Forestry Research and Education, the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), the Animal Welfare Board of India, the Blue Cross of Hyderabad and the University of Hyderabad.

Which environmental preserve in Hyderabad is known to be a home for migratory birds?
Patancheru Lake