932 U.S. NATIONAL MUSEUM BULLETIN 237 part 2 



While we might wish for a more detailed description of this area 

 where the nests of the species were first found and described, it is 

 obviously typical rufous-crowned sparrow habitat. Joseph GrinneU 

 and A. H. Miller (1944) summarize most succinctly the habitats the 

 race rvficeps prefers as follows: "Hillsides that are grass covered and 

 grown to sparse low bushes, scarcely dense enough to constitute 

 true chaparral. Rarely bushes may be absent if rock outcrops are 

 present. Slopes frequented are sunny and well drained. Marked 

 preference is shown for California sage (Artemisia calif omica). This 

 in its typical open growth, associated with grass tussocks, is adhered to 

 exclusively by these sparrows in many areas." 



The mixture of low shrubs and grass they emphasize as this sparrow's 

 prime habitat often includes other plants that they probably use. 

 On the outer coastal mountains Hubert O. Jenkins (1906) found the 

 species at Big Sur and at Mount Mars, Monterey County, where I 

 have seen them in April and December of recent years on the steep 

 slope just above a high sea cliff where golden yarrow (Eriophyllum 

 staechadijolium) , mock-heather (Haplopappus ericoides), low-growing 

 coyote brush (Baccharis pilularis), poison oak {Rhus diversiloba), 

 and many broad-leaved herbs grow amid the sagebrush and grass. 

 However, where the shrubs are too dense in this coastal area rufous- 

 crowned sparrows are absent. 



In the inner coast ranges and presumably the western foothills of 

 the Sierra Nevada, black sage (Salvia mellifera) and other low shrubs 

 mix with or replace the Artemisia, and the grass and other herbs 

 between the shrubs are often much sparser in this area, which is occu- 

 pied by rufous-crowns, than near the coast. J. GrinneU and T. I. 

 Storer (1924) emphasize that scattered low bushes on the driest 

 slopes form this race's habitat at El Portal and Pleasant Valley near 

 the eastern limit of its range in the Sierra Nevada foothills. In both 

 the coastal and inner foothill areas the open spacing of these types of 

 short shrubs, as well as their soft, often wooUy leaves and relatively 

 thin, flexuous twigs characterize the vegetation types known as 

 coastal scrub or coastal sage scrub, as distinct from the taUer, stiffer, 

 harsher-leaved chaparral. 



The rufous-crowned sparrow is, in fact, one of the most characteristic 

 birds of the coastal scrub and undoubtedly reaches its highest popula- 

 tion levels in that type of vegetation, whether on the foggy coast 

 itself or in the sunny interior foothills. This race is also reported 

 occasionally where true chaparral is regrowing after fires and is conse- 

 quently still low and sparse. J. GrinneU (1905d) found them daily 

 from Aug. 29 to Sept. 4, 1904 in a ravine near the base of Black Moun- 

 tain, Santa Clara County, "only on a southern hiUside covered with 

 a low growth of greasewood brush (Adenostoma) ." In the Poso 



