Northern Prairie Wildlife Research Center
The northern harrier, also known as the "marsh hawk", is a hawk of open prairie and wetlands and is common throughout the entire state. The male is a pale gray color and the female is predominantly a streaky brown, but both sexes have a white rump patch which is conspicuous in flight. It can be commonly seen flying low to the ground and spends 50% of the daylight hours searching for prey and perhaps flying about 100 miles every day of its life.
The northern harrier preys mainly on small mammals but also takes many reptiles, frogs, insects, and birds. Prey is usually taken on the ground and only rarely can it capture birds in the air.
The northern harrier breeds from late April to early August and can be seen in North Dakota from April until October. The nest is built on the ground, very often in marshy areas and commonly in low shrubby vegetation, tall weeds, or cattails rather than in very open sites. The female lays an average of 5 eggs over a two week time period, and incubation is done only by the female which lasts an average of 26 days.