994 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 2 



range elsewhere: "Sparsely vegetated, strongly insolated desert ter- 

 rain, either steeply sloping or essentially flat, but not ordinarily the 

 floors of sinks or riparian borders. Most favored are desert uplands — 

 alluvial fans and hill slopes, usually with much exposed rock or gravel 

 pavement. Plants associated include a wide variety but especially 

 favored are cholla cactus and creosote bush, at least where mixed 

 with some other shrubs. Catclaw, small mesquites, artemisia, sages, 

 rabbit-brush, and purshia are other plants which the birds often live 

 in and about." 



In southern California Smyth and Bartholomew (1966) find that 

 "generally black-throated sparrows prefer hillsides to the flatter areas. 

 We never saw them in the floor of the Coachella Valley, but they 

 could be found from the alluvial fans at the foot of the mountains 

 which support little vegetation but creosote bush, up to at least 4,500 

 feet in the San Jacinto Mountains where pinon pine and juniper 

 predominate." 



A. M. Woodbury and C. Cottam (1962) associate the black- 

 throated sparrow mainly with blackbrush (Coleogyne) in much of its 

 range in Utah. William H. Behle (1943) found it "in the creosote 

 bush-Joshua tree associatioa" in the Beaver Dam Mountains of 

 southwestern Utah, however, and mentioned that Merriam had 

 earlier found it ranging up into the junipers in that region. In the 

 Kanab area of southern Utah, W. H. Behle, J. B. Bushman, and C. M. 

 Greenhalgh (1958) found black-throated sparrows in sage and grease- 

 wood along Kanab Creek, but "at Cave Lakes Canyon they occupied 

 a sage-juniper habitat." Edward R. Warren (1913) found the species 

 on "a mesa with scattering cedars and pinons" in Mesa County, Colo. 



Nesting. — W. E. D. Scott (1887), speaking of the Tucson, Ariz., 

 area, gives the breeding season as March through mid-August. This 

 old information still stands for nesting in the southwestern United 

 States, although apparently the extreme months are seldom utilized. 

 Most recorded nesting dates fall in April, May, and June. The 

 protraction of the nesting season into August is probably the result 

 of late renestings or perhaps third broods. J. GrinneU and H. S. 

 Swarth (1913) mention finding a nest on June 1 in the San Jacinto 

 area of southern California and go on to say "This may have been 

 a second set, fuU-grown juvenals being seen on the same date. As 

 young birds at about the same stage of development were secured 

 in this locality late in the summer, August 23 to 27, the nesting season 

 appears to be rather protracted." 



From their studies of the species on the desert slopes of the Santa 

 Rosa and San Jacinto Mountains and in San Gorgonio Pass in southern 

 California in 1964-65, M. Smyth and G. A. Bartholomew (1966) 

 find that song and pair formation usually begin there in February. 



