Marsh-Hawk 167 



posteriorly white with a few pale rufous spots ; iris brown, bill horny, 

 cere greenish-yellow, legs yellow. Length 18 ; wing 13-5 ; tail 8-5 ; 

 culmen 2-9 ; tarsus l-O. 



An adult female is larger — wing 15 ; and is dark umber-brown above, 

 varied with reddish and yellowish-brown ; but the tail-coverts are 

 white, and form a conspicuous mark ; underneath a paler tawny streaked 

 with darker. Young birds resemble the female, and are often darker, 

 but the tail-coverts are always white. 



Distribution. — Breeding from Alaska and Hudson Bay to about the 

 southern border of the United States ; wintering in the southern 

 United States and further south to Panama and Cuba. The Marsh- 

 Hawk is a very common bird in Colorado, especially on the plains, where 

 it breeds. It is not quite so nvunerous in the mountains, though it 

 nests up to about 8,000 feet, and wanders as high as 14,000 feet. It 

 may be considered a summer visitor, though undoubtedly a few birds 

 winter in the plains. 



The following are chief records : Boulder co., wintering in the valley, 

 nesting in hills and plains (Gale & Henderson); Breckrenridge, 

 breeding at 8,000 feet (Carter) ; Orchard, March (Warren) ; El Paso co., 

 February and August (Aiken coll.) ; Wet Mountains, up to 10,000 feet 

 (Lowe) ; Baca co., very common ; Routt co., occasionally (Warren) ; 

 Mesa CO., fairly common, April to November (Rockwell) ; San Juan co., 

 up to 14,000 feet in September (Drew). 



Habits. — ^The Marsh-Hawk frequents meadows and 

 marshy districts, beating to and fro near the surface of 

 the ground with an easy and graceful flight and search- 

 ing for its prey. This consists largely of small rodents, 

 ground-squirrels and meadow mice, and to a lesser extent 

 of frogs, insects and small birds. Occasionally when 

 hard pressed it will take carrion or dead and wounded 

 birds shot by gunners. 



The nest is always placed on the ground, usually in 

 or near a marsh, and is sheltered by a tuft of grass or 

 a bush ; it is a simple structure of dry grass and a few 

 sticks, roughly thrown together, though when used for 

 several successive years, a considerable amount of 



The eggs are usually 4 to 6 in number ; they are greenish- 

 material is accumulated, 

 blue to bluish -white and generally unmarked, though 



