OLD CROW 167 



ward extension of the population which migrates northward along 

 the coast of British Columbia and "much less commonly in the in- 

 terior" (Munro and Cowan, 1947). 



Chen hyperborea hyperborea (Pallas) 



The first flock of nine snow geese, seen on May 20 included in its V 

 formation two Canada geese. This association of two species of geese 

 is often seen in arctic Alaska. Only a few flocks of snow geese were 

 recorded at Old Crow, aU in V formation and flying steadily eastward. 

 It is reported by Indians that snow geese, which they call Kookeh, 

 occasionally land on Crow Flats, where they are more often noticed 

 than at Old Crow. Peter Lord reported that he first saw snow geese 

 on the Flats on May 16, but that they always pass northward and do 

 not remain in summer. The size of the flocks of snow geese and the 

 numbers sighted vary from year to year at Anaktuvuk and from 

 reports of the Indians, a similar variation appears to occur at Old 

 Crow. 



Dall (Dall and Bannister, 1869) found snow geese common in spring 

 at Nulato, where they arrived on May 9 flying up the river. Eand 

 (1946) gives no reports on snow geese in southern Yukon, and Swarth 

 (1936) saw only three at Atlin — two on May 5, 1932, and one on 

 May 5, 1934. It seems likely that the eastward flight at Old Crow 

 brought snow geese from the Pacific Coast. Those which we saw 

 were flying rather low and their numbers would not make a substantial 

 contribution to the numbers nesting from the Mackenzie eastward. 

 But since these geese often fly high over mountains we may have 

 missed seeing most of the migration. 



At Fort Yukon, wrote Murray to Kichardson (1852, p. 305), the 

 snow geese arrive about May 15 or 16 and "breed only on the shores 

 of the Arctic Sea. They return in September and early October, flying 

 high and seldom halting." 



Subfamilies Anatinae and Aythinae: Ducks 



Of the 14 species of ducks at Old Crow, two have holarctic nesting 

 areas, two are not quite so widely distributed in the Arctic, and 10 

 are restricted in arctic nesting to Alaska, Yukon and Mackenzie. 

 East of central Mackenzie the northern border of nesting by these 

 species extends southeasterly to the southwestern shore of Hudson 

 Bay about parallel to but usually somewhat north of the forest. The 

 northern limit also runs about parallel to the steeply declining iso- 

 thermal gradient of summer temperatures which marks the extension 

 of summer warmth far northward in western North America. East 

 of the Mackenzie River the physiographic features also change, for 



469496—60 12 



