Birds migrate, so do a lot of other species of animals. Migration is to move from one region of habitation to another region in search of various needs of life. Birds migrate mostly from the Northern Hemisphere to the Southern Hemisphere, during the winter months. The winters are colder and harsher in the Temperate Zones and Warmer and Congenial in the Tropical Regions.
The birds in the pictures here are one such species of birds — the Bar-headed Geese - Anser indicus, the highest flying migratory bird. These birds start their winter journey from the lakes in the Central Plains of Mongolia, flying at an altitude of 30,000 ft. where the temperatures reach as low as -60 degrees, which can freeze our blood and kill us in an instant, all the way crossing the treacherous Himalayas, higher than the tallest mountain peak — the Everest, and reach the Plains of India, to spend their winter.
