Yellow-headed Blackbird 305 
Distribution.—Breeding throughout central and western North 
America from Illinois and Indiana to British Columbia, southern 
California and northern Mexico, wintering in the southern part of its 
breeding range and in central and southern Mexico. 
In Colorado the Yellow-headed Blackbird is a common summer 
resident, breeding in suitable localities in the plains and in the moun- 
tains up to about 8,000 feet. It has been recorded from Weld co. 
(Markman), Boulder co. (Henderson), Barr Lakes, where it is extremely 
abundant (Rockwell & Hersey), Lincoln and El Paso cos. (Aiken) 
and Baca co. (Warren), in the plains and foothills; from Middle 
and South Parks, breeding (Carter apud Cooke), Routt co. (Warren), 
Grand Junction (Rockwell), Chaffee co., breeding near Buena Vista, 
about 8,000 feet (Keyser), Costilla co., breeding at San Louis Lake, 
(Henshaw & Aiken), Twin Lakes, about 9,000 feet (Scott), Archuleta 
co. (Henshaw) and Montezuma co., breeding near Cortez (Gilman). 
It arrives about the middle of April, and departs south in September. 
Habits.—The Yellow-headed Blackbird is a gregarious 
bird, and is found in flocks throughout the year; during 
the summer it resorts to sloughs and marshes, where 
it breeds, in company often with other species; later 
in the season it is generally to be found in the grain- 
fields in large flocks, and there, when in sufficient 
numbers, it commits considerable havoc. It is seldom 
met with in arid or thickly-wooded country. 
Its food consists of the seeds of grasses and weeds 
in addition to grain, while chiefly in the middle of the 
summer it devours large numbers of insects. 
The nests are large and bulky, attached to several reeds 
or rushes about ten to thirty inches above the water, 
and constructed almost entirely of coarse grasses and reeds, 
with a lining of finer material of the same sort—no mud 
being made use of (Plate 13). Fresh eggs are to be 
found about the end of May as a rule, but there is a 
good deal of irregularity about the times of laying, and 
unfinished nests, freshly-laid eggs and nestlings are often 
met with in one colony at the same date. The eggs, 
usually about four in number, are whitish, profusely 
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