331. Circus hudsonius. 19 in.

Upper tail coverts and base of tail white. Male, blue-gray above; below whitish, streaked and barred with rusty. Female and young. - Above rusty brownish-black; below rusty with dusky streaks on the breast and sides. As shown by its name, this hawk is found most abundantly in or around marshes or wet meadows. I have found them especially abundant in boggy marshes such as frequented by bitterns. Their flight is quiet and owl-like, and as they do most of their feeding toward dusk, they often seem like owls as they flit by without a sound. Their food is composed chiefly of meadow mice and moles, which they spy and dash down upon as they fly at low elevations.

Notes. - A shrill whistle when their nest is approached.

Nest. - Of grasses, on the ground in marshes; four plain bluish-white eggs. (1.80 x 1.40); May, June.

Range. - Breeds locally in the whole of the United States and Canada, north to Hudson Bay; winters in the southern half of the United States.