The Brewer Blackbird 



but they are somewhat more independent than most, flocks of one or two 

 score being more frequent than those of a hundred. During migration 

 and in winter flocking they associate more or less with Redwings; but, 

 although 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. The water 

 may be that of river, lake, or horse-pond. A watering-trough, if its 

 supply be constant, will have its devoted circle of black admirers, and 

 especially if it also assures the presence of cattle. In some places their 

 attendance upon horses or cattle is so close that they almost fulfil the 

 function of Cowbirds. Being omnivorous as well as adaptable, the 

 grain wasted by feeding animals is consumed by these birds as greedily 

 as are the insects which annoy them. Familiarity with domestic animals 

 may reach the point where the birds are suffered on the back; and Mrs. 

 Bailey tells us that in the Escondido country the birds take toll of the 

 sheep's backs at nesting time. 



Although isolated nests may now and then be found, colonies are 

 the rule; and we sometimes find as high as twenty nests in a single tree, 

 or forty in a given patch of greenery. There is, of course, room even here 

 for individual choice of nesting sites; but the community choice is far 

 more striking. Thus, one recalls the grease-wood nesting, the mistletoe 

 nesting, the rose-briar nesting, the Monterey cypress nesting, where all 

 the members of the colony conform to the locally established rule in nest 

 position. J. H. Bowles records a most remarkable instance of this in 

 Washington. One season the nests in the South Tacoma colony were 

 all placed in small bushes, the 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 stub, none of them less than 150 feet from 

 the ground. 1 Mr. Tyler 2 found them breeding at Shaver Lake (elevation 

 5300 ft.) in the old dead pine stubs standing out in the water. And Mr. 

 Ray 3 reports their nesting at Lake Tahoe in the crannies of rotting piles. 

 Numerous instances are on record where nests have been placed on the 

 ground, and sometimes entire colonies will adopt this indolent and un- 

 questionably hazardous method. 



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 

 mould, or matrix, of dried cow-dung or mud, which gives form and stability 

 to the whole. The lining almost invariably includes fine brown rootlets, 

 but horsehair is also welcomed wherever available. 



'"The Birds of Washington." Vol. 1, p. 47. 1909. 



'John G. Tyler in "The Condor." Vol. XL. May 1909. p. 83. 



3 Milton S. Ray. "The Condor." Vol. XI.. Nov. 1909. p. 193-196. 



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