Marsh Hawk, or Northern Harrier, a bird of prey that lives in marshy or grassy areas of North America; it is the only harrier found in the Americas. The bird has long, yellow legs, a long tail, and an owl-like, disc-shaped face. The male, about 20 inches (50 cm) long, has a bluish-gray back, black wingtips, a white rump, and whitish under-parts. The slightly larger female is dark brown with buff streaks.

Marsh hawks hunt while flying close to the ground. They feed chiefly on mice, small birds, frogs, and snakes. Four to six bluish-white eggs are laid in a grass nest built on the ground. The young mature in about two years.

The marsh hawk is Circus cyaneus hudsonius of the hawk family, Accipitridae.