BIEDS OF THE PAPAGO SAGUAKO NATIONAL, MONUMENT. 33 



feet from the ground and with connecting crossbars at intervals. 

 On the topmost crossbars there is just room for a nest, wedged 

 in between the uprights, and this is the place universally chosen. It 

 seems a peculiar preference to select a place so exposed to the 

 glaring sun rather than the shady cottonwoods along the road- 

 side; but the kingbirds of the country are so evidently of one mind 

 as to the suitability of their choice that there is a nest, new or old, 

 in every third or fourth pole along the roads. 



The western kingbird occurs in some numbers about Eoosevelt 

 Lake, and is one of the species that was seen regularly about the 

 hotel. In the near-by Sierra Ancha it is replaced by the closely 

 similar Cassin kingbird (Tyrannus vociferans}. 



DWARF COWBIRD. 



Molothrus ater obscurus (Gmelin). 



Recognition marks. About 7 inches long. Male, glossy black, 

 with brown head; female, uniform dull brownish; eye, brown. No 

 red, white, or other contrasting markings in either sex. 



Occurrence. In all the valleys of southern Arizona the dwarf 

 cowbird occurs in numbers during the summer months. Through 

 the winter it is found commonly in the valley of the Colorado River, 

 but apparently not elsewhere in the State. Cowbirds are common 

 through the country traversed by the Apache Trail, usually seen in 

 small flocks, quite free of the care and worry of family duties. The 

 species is especially numerous, together with the redwings, in the irri- 

 gated farming lands, where cultivation of the ground produces an 

 abundance of food; while the presence of cattle and horses provides 

 associations to which the cowbird is especially addicted, as is in- 

 dicated by the bird's name. The species may be seen also, however, 

 over the most arid desert; in fact, certain of the desert birds are 

 among those most frequently victimized by the cowbird. The 

 plumbeous gnatcatcher is one that seems especially to suffer from 

 the cowbird's visitations ; it is an especially pathetic sight to see one 

 of these tiny birds acting as parent, and poking hopelessly in- 

 adequate mouthfuls of food into the gaping bill of her enormous 

 foster child. One can imagine the gnatcatcher's feelings of relief 

 when the strain is over and the foundling has betaken himself to his 

 kindred; but with the relaxation following the deliverance there 

 must be a feeling of having passed through a peculiarly wearing 

 summer with nothing to show for it at the end. 



The dwarf cowbird does not, as a rule, ascend the mountains above 



the foothills, but aside from this the species is not closely bound by 



environmental conditions. As long as other small birds are able to 



build nests and rear young the cowbird is willing to put up with the 



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