466 ANIMAL LIFE IX THE YOSEMITE 



Xo Other bird of any species was encountered during our stay in this 

 area of an acre or more. It would seem that the Bell Sparrow, at least 

 at nesting time, closely restricts itself to a type of territory such as is not 

 sought out by other birds; it is not consequently bothered by competition. 



Mo\dng on to the next little hillslope we observed another singing male 

 Bell Sparrow; a careful examination of the many hillsides in the basin 

 of Blacks Creek would probably have revealed a pair of Bell Sparrows on 

 each one. Hence, while the number of Bell Sparrows to be found in any 

 one limited area is small, the total population in the entire greasewood belt 

 of the western foothills must be large. As already stated, not one of these 

 birds is likely to come to the attention even of the careful bird student 

 save as he or she makes particular effort to find the species. 



Nevada Sage Sparrow. Amphispiza nevadensis nevadensis (Ridgway) 



Field characters.— Slightlj larger than Jimco or Bell Sparrow. Whole bird gray- 

 toned; upper surface of body, wings and tail, ashy brown; head pure ashy gray (pi. 8/i) ; 

 under surface white with a dusky spot on center of breast ; a broad streak of dull black 

 runs from bill through eye, and there is a narrower dark gray stripe on each side of 

 throat. Voice: As for Bell Sparrow. 



Occurrence. — Common summer visitant to Transition Zone east of Sierra Nevada. 

 Observed widely about Mono Lake and around Mono Craters. Habitually in sagebrush. 

 In pairs or scattering companies; never in close flocks. 



The Nevada Sage Sparrow is the counterpart of the Bell Sparrow and 

 takes the niche of that bird on the east side of the Sierra Nevada, where 

 sagebrush takes the place of the greasewood of the west slope. In various 

 portions of the plains-like, sage-covered country about Mono Lake these 

 sparrows were seen in moderate numbers during mid-September, 1915. In 

 the spring and early summer of 1916 they were met with only once, on 

 June 20, close to the old Salmon Ranch near Mono Lake Post Office. 



Sage sparrows do all their foraging upon the ground between bushes, 

 where they hop about in a peculiar hesitating manner. When alarmed 

 they run with astonishing celerity, being able easily to keep several bushes 

 between themselves and their pursuers. If closely pressed they take to 

 flight and scatter out, to drop out of sight again shortly. When singing, 

 and often at other times, individuals will perch many minutes at a time 

 at the tips of tall bushes, where they are visible considerable distances over 

 the sea of sage. 



