|Common Name||Tyrant Hawk-eagle|
|Range||central Mexico to eastern Peru, the south of Brazil, and far northern Argentina.|
The Black hawk-eagle (Spizaetus tyrannus), also known as the tyrant hawk-eagle, is a species of bird of prey found from central Mexico to eastern Peru, the south of Brazil, and far northern Argentina. Its preferred habitats include humid and moist forests close to rivers, and several types of woodland. It is uncommon to fairly common throughout most of its range. Its closest relative is the ornate hawk-eagle, which is similar in size, appearance and behavior but lives at lower elevations.
The black hawk-eagle is 58–70 cm (23–28 in) long and weighs about 900-1,300 grams (2-2.9 lbs). It has black plumage with varying patterns on its wings and body, and white speckling in places. It has barred wings, slightly elliptical in shape, and a long, narrow tail which is rarely fanned. The four grey bars on the tail are distinctive to the black hawk-eagle, as is the white line seen slightly above the bird's eye. While flying, the broadness and shortness of the wings become apparent. While in flight, the bird's tail is typically kept closed.
Though light and small compared to other eagles, this bird is a powerful predator that frequently hunts relatively large prey. It mainly eats large rodents, opossums and monkeys, as well as, occasionally, bats and birds. Its popular name in Brazil is "Gavião-pega-macaco", which means "monkey-catching hawk". The birds it takes can be quite large, such as toucans,and chachalacas. The dietary habits of the black hawk-eagle, however, remain largely unknown, with no known comprehensive list of prey species.
Like its diet, the black hawk-eagle's breeding behavior is little known other than some details relating to its nest: composed of sticks and possibly other materials, the nest is around one metre and a half in total diameter and is usually constructed in tall trees, often around fifteen metres high. The variety of tree chosen probably varies greatly, but they have been observed chiefly in pine trees.