_Circus hudsonius. Case 3, Fig. 15_
The immature bird and adult female are dark brown
above, reddish brown below, but, in any plumage,
the species may be known by the white upper
tail-coverts which show clearly in flight. L.,
male, 19; female, 22.
_Range._ North America, wintering from New Jersey
southward; migrates northward in March.
Washington, common W.V., July-Apl. Ossining,
tolerably common S.R., Mch. 6-Oct. 30; a few
winter. Cambridge, common T.V., Mch. 20-Nov. 10,
one breeding record. N. Ohio, not common S.R.,
Mch. 5-Nov. 30. Glen Ellyn, S.R., several pairs,
Apl. 4-Nov. 6. SE. Minn., common S.R., Mch. 6-Nov.
1.
The Marsh Hawk quarters low over the fields turning sharply here and
there to follow the course of a meadow mouse in the grass forest below.
As a rule the bird is silent but in the mating season he repeats a
'screeching' note. The nest is made on the ground in the marshes; the
4-6 white eggs are laid in May.