The Vesper Sparrows 



if more than one brood is raised. The Western Vesper Sparrow is not 

 by any means so common in California during the breeding season as it 

 is in the more northern states, and its breeding range seems to be confined 

 chiefly to the plateau region east of the Sierras, from Owens Valley north. 

 I have found it most commonly in Long Valley in southern Mono 

 County, where, in association with the Brewer Sparrow and the Sage 

 Thrasher, it is one of the most characteristic birds of the dwarf-sage belt, 

 which skirts the lowermost slopes of the mountains. It is also a familiar 

 figure along the crests of the White Mountains; and we have an egg in 

 the M. C. O. collection which was taken there at an elevation of 10,000 feet. 

 There has been a notable shifting of this species within historic times. 

 This change has been marked by a vigorous and successive encroachment 

 along the northern limits of the breeding area, and, as nearly as we can 

 make out, by a corresponding retirement from southern territory. As 

 in so many other instances, the movement in California has been altitud- 

 inally upward, with a resultant reduction of area. 



No. 40b Oregon Vesper Sparrow 



A. O. U. No. 540b. Pooecetes gramineus affinis Miller. 



Synonyms. — Pacific Vesper Sparrow. Miller's Grass Finch. 



Description. — Similar to P. g. confinis but smaller and coloration darker, 

 browner above, more distinctly buffy below. Length of adult male about 146 (5.75); 

 wing 77.2 (3.04); tail 57.9 (2.28); bill 10.9 (.43); tarsus 20.6 (.81). Female a little 

 smaller. 



Nesting. — Not known to breed in California. As in preceding subspecies. 



Range of P. g. affinis. — The Pacific Coast region; in summer from British Co- 

 lumbia to northwestern Oregon; in winter, California west of the Sierras to Cape San 

 Lucas. 



Distribution in California. — Winter resident and migrant west of the Sierras. 

 Range imperfectly distinguished from preceding in winter, and doubtless overlapping 

 it in southern portion. 



Authorities. — Newberry (Zonotrichia graminea), Rept. Pac. R. R. Surv., vol. 

 vi., pt. iv., 1857, p. 88;Grinnell, Pasadena Acad. Sci. Pub., vol. ii., 1898, p. 36; Wittard, 

 Bull. Cooper Orn. Club, vol. i., 1899, p. 30; McGregor, Condor, vol. ii., 1900, p. 25\Grifi?iell, 

 Pac. Coast Avifauna, no. 11, 1915, p. 113; Swarth, Condor, vol. xix., 1917, p. 130. 



THE VESPER Sparrows are a very much less conspicuous element 

 of the Californian avifauna than of that found in the regions to the north 

 of us. Confinis does not breed in this State, though suitable "prairies" 

 are not lacking in Trinity or Siskiyou counties. Known only, therefore, 

 as a winter resident and migrant, it seeks the open situations of the 



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