1914] Grinnell: Mammals and Birds of the Colorado Valley 187 



Bombycilla garrula (Linnaeus) 



Bohemian Waxwing 



Known from the region only from the female specimen, now no. 

 4207 in this Museum, taken by J. G. Cooper at Fort Mohave, January 

 10, 1861. 



Phainopepla nitens (Swainson) 

 Phainopepla 



Everything indicated that this bird was common as a permanent 

 resident of the region. It was, however, closely restricted to two 

 narrow belts paralleling the river, one on each side; namely as con- 

 stituting the mesquite association. The close coincidence of the range 

 of the bird with the plant association in question was here clearly 

 due solely to the preferred food afforded in constant and abundant 

 quantity by the berries of the mistletoe parasitic upon the mesquite. 

 Judging from experience elsewhere, there is reason to believe that 

 the phainopepla would have availed itself of edible berries in what- 

 ever part of the region these might have been produced. Yet the 

 fact remained that in the Colorado Valley the bird's presence and 

 distribution was remarkably controlled by those of the mesquite; 

 where there were no mesquites, as at our station near Pilot Knob, not 

 a phainopepla was seen; where the mesquite had amassed itself into an 

 extensive belt, the birds abounded. 



In certain places, as on the Arizona side above Mellen, and on 

 the California side opposite Cibola, this bird was. within the riparian 

 strip, the most abundant single species. In such localities the birds 

 overflowed in small numbers a little way up contiguous desert washes, 

 foraging about palo verdes or ironwoods, which latter plant occasionally 

 bore mistletoe clumps. 



The phainopepla nested earlier than most of the resident birds of 

 the region. Bob-tailed young out of the nest were seen April 12 on 

 the California side, twenty miles above Picaeho. April 5, on the same 

 side opposite Cibola, two nests were found, each containing two eggs 

 nearly hatched. In one of these cases the nest was eight feet above 

 the ground on a branch of an ironwood ; in the other, sixty-two inches 

 above the ground on a mesquite limb. A nest with three fresh eggs 

 found April 11 at the first-named locality, was seven feet above the 



