General
Northern Harrier: Large hawk with gray upperparts; distinct white rump with a dark gray band along the trailing edge of the primaries; white underparts with spotted breast. Eyes are yellow. Wings are long; gray above and white below with black tips. Female is larger; dark brown above, paler below with dark streaks; dark bands on primaries, secondaries and rectrices; white rump. Juveniles resemble adult female but are slightly darker above and more cinnamon below. Is commonly seen gliding low in search of prey.
Range and Habitat
Northern Harrier: Breeds in North America from Alaska east to subarctic Newfoundland and Labrador and south to the northern states. Resident population across U.S. from Pacific Coast to the Great Lakes. Spends winters southwest and Pacific coast through Mexico and the West Indies to Central America. Preferred habitats include open fields, savannas, meadows, and marshes.
Breeding and Nesting
Northern Harrier: Breeding usually takes place from April to July. Three to nine pale blue eggs, sometimes spotted with brown, are laid in a ground nest made of sticks and lined with grass. It is usually built on a raised mound of dirt or a clump of vegetation. They often nest in loose colonies of 15 to 20 pairs. Incubation ranges from 31 to 32 days, and is carried out by the female.
Foraging and Feeding
Northern Harrier: Their diet includes rodents, reptiles, insects, frogs and birds, chiefly passerines and small waterbirds. They glide close to the ground when hunting, diving quickly to capture prey. They forage over open habitats, such as prairies, uplands and marshes. They virtually always hunt on the wing, coursing low over the ground with a buoyant, gliding flight; flaps intermittently.
Vocalization
Northern Harrier: Emits a shrill call of "kek, kek, kek" or "keee, keee, keee", especially around the nest.
Similar Species
Northern Harrier: Rough-legged Hawk has broader wings, a heavier body, and black subterminal tail band.