The Migration of North American Sparrows 



TWENTY-FIFTH PAPER 



Compiled by Prof. W. W. Cooke, Chiefly from Data in the Biological Survey 



With drawings by Louis Agassiz Fuertes 



(See Frontispiece) 



ALEUTIAN ROSY FINCH 



As its name implies, the Aleutian Rosy Finch has its principal home on those 

 islands, whence it ranges north to the islands of Bering Sea and east to the 

 western part of the Alaska Peninsula. It breeds and winters on that region, 

 though in the latter season some individuals straggle east as far as Kodiak 

 Island. 



GRAY-CROWNED ROSY FINCH 



The tops of the high mountains above timber-line are the chosen summer 

 homes of the Gray-crowmed Rosy Finch. Here it is found in a long narrow belt 

 that includes the highest peaks from east-central Alaska to western Alberta; 

 on the White Mountains and the southern Sierras of east-central California. 



The individuals of this species that breed along the coast mountains of 

 southeastern Alaska, and south to the higher peaks of Washington and north- 

 ern Idaho, have been separated under the name of Hepburn's Rosy Finch. 



During the winter, both these forms spread over much of the lower parts 

 of the mountains south to Colorado and California and east on the plains to 

 Manitoba and Nebraska. Flocks often contain birds of both forms, but in 

 the Rocky Mountains and on the plains the Gray-crowned is the more com- 

 mon, while to the westward the Hepburn's becomes commoner, though even 

 as far west as southeastern Oregon the Gray-crowned is often as abundant as 

 Hepburn's. 



The birds begin to descend to the lower parts of the mountains in Septem- 

 ber (September 20, 1870, Uintah Mountains, Utah), but rarely appear in the 

 foothills before early October. Some dates of fall arrival are: Big Sandy, Mont., 

 October 1, 1900, October 3, 1906; Terry, Mont., October 18, 1903, November 

 1, 1904; Anaconda, Mont., October 29, 1910; Lewistown, Mont., October 30, 

 1899; Laramie, Wyo., October 25, 1898; Magnolia, Colo., November 27, 1895; 

 Park County, Colo., November 26, 1910; Camp Harney, Ore., November 8, 

 1875. The above dates of fall arrival all refer to the Gray-crowned race, but 

 the other form migrates at approximately the same time. 



The return movement begins in February, and the last birds leave 

 Nebraska the latter part of that month; the last was noted at Camp Harney, 

 Ore., March 22, 1876, and at Salt Lake, Utah, March 21, 1850; Terry, Mont., 

 March 13, 1904; Columbia Falls, Mont., April 6, 1893; Banff, Alberta, April 

 7, 1903, April 18, 1908; Stony Plain, Alberta, April 16, 1908, and April 3, 1909. 

 The type specimen of this form was taken on the Saskatchewan plains in May, 

 but this is unusually late for the bird to be away from the mountains. 



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