Vol. XX 

 1903 



n Brown, Arizona Bird Notes. A'l 



to the three-story nest of a Sonora Yellow Warbler and its efforts 

 not to raise a brood of bastards. The first or lower nest con- 

 tained one cowbird egg and one warbler egg, the second two cow- 

 bird eggs and several broken shells of the warbler, the third con- 

 tained one egg of each bird and had been abandoned. Between 

 the first and second lot of eggs the nest had been thickly padded ; 

 between the second and third lots the padding was not so thick, 

 but was sufficient to thoroughly cover the objectionable eggs. I 

 have seen numerous nests of small birds, most of which contained 

 one or more eggs of the Cowbird. Double nests are quite com- 

 mon, the Cowbird eggs being entirely padded over. One of these 

 double nests was that of a Sonora Yellow Warbler. It was a 

 beautiful thing. The lower nest contained three fresh eggs of the 

 mother bird and one Cowbird egg, the upper one three legitimate 

 eggs. Occasionally, but not often, I have found Cowbird eggs in 

 the nests of larger birds than themselves, notably in those of 

 Abert's Pipilo, but the predisposition is in favor of the nests of 

 vireos, warblers and small flycatchers. This is carried on to such 

 an extent on the lower Gila that it is almost impossible to find a 

 nest of any of the foregoing birds that does not contain one or 

 more of the eggs or young of the Cowbird. To my knowledge 

 more than one hundred eggs of this parasite were taken from 

 nests and destroyed during the past season. 



Blackbirds announce their arrival here not later than October 

 first, sometimes a week or two earlier, and from thence on they 

 drift along towards the latter part of the month. Young birds 

 have come in as late as October 20. Their short tails and persist- 

 ent demands on the other birds for food precluded any mistake 

 as to their age. The Redwings and Brewer's make themselves 

 at home wherever they can get food, but the Yellowheads go 

 lower down the valley and have a fondness for working over 

 refuse in stock corrals, straw stacks and wheat fields. The spring 

 migration commences by the middle of April and by the end of 

 the month nearly all are gone. These dates will hold about good 

 for the average year, but 1892 was different from anything I had 

 heretofore seen. The birds did not get away for a month later. 

 Small bunches of Redwings nest in the willows and arrow weeds 

 ■on the Gila and make odd visits to their old feeding grounds dur- 



