70 NORTH AMERICAN DUCKS, GEESE, AND SWANS. 



the principal route coincides with the districts in which the species is 

 most common. The greater number pass from the breeding grounds 

 to Great Slave Lake and Lake Athabasca, continue south to central 

 and western Montana, and then turn southwest, cross the Rocky- 

 Mountains, and pass to central and southern California. 



'Spring migration. — Records that are in close agreement indicate 

 that the average date of arrival in spring at Great Falls, Mont., is 

 April 7, and at Columbia Falls, Mont., April 8. The average date at 

 which the last one was seen in central Montana is April 24. The birds 

 were noted on the lower Athabasca River May 31, 1903, and one was 

 taken May 25, 1865, at Fort Anderson, near the Arctic coast. The 

 latest spring records are of its occurrence at Lake Athabasca, June 3, 

 1903, and at the base of Kent Peninsula, Arctic coast, June 2, 1902. 

 The record of one taken near Camp Harney, Oreg. , April 12, 1876, 

 seems to be the only one for that State. A few have been taken in 

 southern British Columbia at Shuswap Lake, Kuper Island, and the 

 mouth of the Fraser River; one was taken at Fort Keogh, Mont., 

 April 25, 1892. 



Fall migration. — The returning flocks have been recorded at Great 

 Slave Lake, September 1, 1893, at Columbia Falls, Mont., October 10, 

 1893, and at Newport, Gal., November 10, 1900. The average date of 

 arrival at Columbia Falls, Mont., is October 15, and the latest date 

 October 28, 1896. A straggler was taken at Winnipeg, Manitoba, 

 September 20, 1902. 



Auser albifrons (Gmel. ). White-fronted Goose. 



The typical species inhabits Europe and Asia, and is reported as 

 having been taken in May and September at Angmagsalik and Tasin- 

 sak in eastern Greenland. 



Anser albifrons gambeli (Hartl. ). American White-fronted Goose. 



BreeoZing range. — This goose breeds on the shore of the mainland 

 from the mouth of the Yukon around the north side of Alaska and 

 east to Lake Beechey on Back River; also coastwise for a few miles 

 back in northern Mackenzie, and up the Yukon at least as far as Fort 

 Yukon. The birds seen by Preble at Fort Wrigley, on the Macken- 

 zie, July 23, 1904, may or may not have been breeding; a few nest on the 

 coast of northeastern Asia in the vicinity of Bering Strait. 



In giving the above range no mention is made of the birds that breed 

 on the west coast of Greenland, where the species is not uncommon. 

 It is evident from Labrador and Atlantic coast records that Greenland 

 birds do not come to the southwest; hence they probably go to the 

 southeast, and should be classed as European birds. 



Winter range. — The white-fronted goose winters in the whole south- 

 ern half of the United States and south to Cuba and northern Mexico. 



