THE BREWER BLACKBIRD. 47 



Like all Blackbirds, the Brewers are gregarious ; but they are soiiicw hat 

 more independent than most, flocks of one or two score l)eing more freijuent 

 than those of a hundred. During migrations and in autumnal flocking they 

 associate more or less with Redwings; but. altho they are devoted to the 

 vicinity of water, they care nothing for the fastnesses of reed and rush, 

 which are the delight of Redwing and Yellowhead. Their preference is for 

 more open situations, so that they are most abundant upon the East-side. 

 Here a typical breeding haunt is a strip of willows fringing a swamp; or, better 

 still, a line of dark green thorn-bushes clinging to the bank of the rolling- 

 Columbia. 



Altho isolated nests may now and then be found, colonies are the rule ; 

 and I have found as high as forty nests in a single patch of greenery. There 

 is room, of course, for individual choice of nesting sites, but the com- 

 munity choice is the more striking. Thus, one recalls the greasewood 

 nesting, the rose-briar nesting, the thorn-bush nesting, where all the members 

 of the colony conformed to the locally established rule in nest position. 

 Mr. Bowles records the most remarkable instance of this : One season the 

 nests of the South Tacoma colony were all placed in small bushes, tlie 

 highest not over four feet from the ground; but in the season following the 

 birds were all found nesting in cavities near the top of some giant fir stulis, 

 none of them less than 150 feet from the ground. (3n the other hand, in 

 the Usk nesting of 1906, on the placid banks of the Pend d'Oreille, one 

 pair had recessed its nest in a stump at a height of eighteen feet, while three 

 other pairs had sunk theirs into the ground at the base of bushes. 



In construction the nest of the Brewer Blackbird varies considerably, 

 but at its best it is quite a handsome affair. Composed externally of twigs, 

 weed-stalks, and grasses, its characteristic feature is an interior nmuld. or 

 matrix, of dried cow-dung or mud. which gives form and stability to the 

 whole. The lining almost invarialily includes fine brown runtlets. but Imrse- 

 hair is also welcomed wherever available. 



The eggs of Brewer's Blackbird are the admiration of otologists. Rang- 

 ing in color from clear greenish gray with scattered markings thru denser 

 patterns to nearly uniform umber and chocolate, they are the natural favorites 

 of "series" hunters. The range of variation is, indeed, curious, but it proves 

 to l)e entirely individual anil casual without trace of local or constant differ- 

 ences. Eggs from the same nest are usually uniform in coloration, but e\cn 

 here there is notable diversity. In some instances, after three or four eggs 

 are laid, the pigment gives out. and the remainder of the set is lighter colored. 

 Again, single eggs are heavily pigmented half way, and finished with a clear 

 green groinid-color. 



