Yellow-headed Blackbird 305 



Distribution. — Breeding throughout central and western North 

 America from IlUnois 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), Bovilder 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. (HeiLshaw) 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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