52 



MIGRATION ROUTES AND FLYWAYS 



With the exception of the tributary routes from the Bear River 

 Marshes, this also is a relatively simple flyway, as the majority of the 

 ducks that use it make direct north and south journeys from breeding 

 grounds in central Canada and other northern regions to their winter 

 quarters, which are chiefly in Texas. 



THE PACIFIC FLYWAY 



The Pacific flyway (fig. 35) presents some interesting peculiarities. 

 While the map shows a route that follows the coast of British Columbia, 

 it should be pointed out that this is riot an important lane of travel for 

 many of our game ducks, but it is followed chiefly by the diminutive 

 Cackling Goose, the Black Brant, and some of the sea ducks. There is, 

 however, an offshore flight of Pintails and possibly other ducks, the 

 origin and destination of which is at present incompletely understood. 

 The Cackling Geese that 

 breed in the delta region of 

 the Yukon River in Alaska 

 follow this route across the 

 Alaskan Peninsula, the Gulf 

 of Alaska and along the coast 

 of British Columbia, turning 

 into the interior near the 

 mouth of the Columbia 

 River. Proceeding eastward 

 only a short distance they 

 again turn south to their 

 winter quarters at Tule Lake 

 Wildlife Refuge, on the Ore- 

 gon-California line, and in 

 the Sacramento Valley of 

 California. A few continue 

 southward as far as the 

 northern part of the San 

 Joaquin Valley. 



Most other geese, includ- 

 ing the greatly reduced Ross's 

 Goose, and ducks that use the 

 United States part of this 

 flyway, however, come from 

 eastern Alaska, Mackenzie 



Valley, and other interior points. Again, the great breeding grounds of 

 central and northwestern Canada and eastern Alaska produce most of the 

 birds killed by California and Oregon sportsmen. Starting in Alaska, 

 Yukon, and Mackenzie, this route which also is used in common by 

 many birds that are to follow other flyways runs southward through the 

 Prairie Provinces. The Pacific flyway contingent probably parallels 

 closely the eastern foothills of the Rocky Mountains. The route branches 



Fie. 35.-The Pacific Flyway 



