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The heaviest bird known from fossils is Stirton's Thunder Bird (Dromornis stirtoni), sometimes called Mihirung birds, meaning giant bird in one of the Aboriginal languages. Adults are estimated to have stood 3 meters tall and weighed 500 kilos (1100 pounds). It lived in open woodlands in what is now the Northern Territory of Australia during the Late Miocene. Although Australian, it is more closely related to geese than emus. (The nickname demon duck of doom, sometimes applied to Dromornis, more properly refers to Bullockornis planei.)
longest flier: Sooty shearwaters migrate nearly 40,000 miles (64,000 kilometers) a year, flying from New Zealand to the North Pacific Ocean every summer in search of food.