HOMEWARD MIGRATION 



ward the Libau Marsh on Lake Winnipeg. With the breeding range of ducks 

 spread so widely over the northland, the pattern of homeward migration 

 must eventually show as many divisions as there are pairs in flight. In south- 

 ern regions there are common channels for many thousands of birds. Then 

 come major migratory divides where large groups turn toward one or another 

 breeding region. When the nesting grounds are reached, the routes branch 

 again and again to accommodate each small band until every pair has finally 

 gained its own home range. This requirement for division is the reason for 

 the smaller size of spring flocks. 



Some, of course, may take the wrong turn or continue with the main 

 stream when they should have separated from it. The experience of Sowls 

 (1955:15) with his color-banded adults, however, is evidence of the effici- 

 ency of spring passage. His marked ducks arrived on their Delta home range 

 with the very first flights of spring, the promptness of this return suggesting 

 a direct passage from the last stopping place. 



Awareness of the direction of the destination is suggested by the be- 

 havior of the Blue Geese and Lesser Snow Geese when they leave the prairie 

 country in May. They have traveled north up the Mississippi Valley to 

 Canada ; but they now turn northeast, and if the line of their flight, as seen 

 in the Delta region, is plotted on a map (Figure 16) it points directly to the 

 region of James Bay, which is their next stopping place (Soper, 1930, 1942). 

 Hickey (1943:28) once "enjoyed a mellow April evening with two friends 

 atop the Palisades along the lower part of the Hudson River near New York 

 City. Hundreds of scaups began flying over our heads at 5:44 p.m. Leaving 

 Long Island Sound, a few miles eastward, the birds were headed in a west- 

 northwest direction over New Jersey's Hills — supposedly for the Finger 

 Lakes." Bent (1925:131) tells how the May departure of White-winged 

 Scoters from the New England coast aims for the Canadian prairie breeding 

 grounds. In 1953 the first Canada Geese seen at Delta flew straight north 

 over the village, and we learned from Ralph Otto that Canadas reached their 

 Dog Lake nesting grounds, sixty miles due north of Delta, later the same 

 day. Probably the birds we watched were headed straight for Dog Lake. 



Sometimes we are fortunate enough to witness the actual splitting of a 

 migration. On the morning of April 20, 1952, I saw a steady stream of 

 Canada Geese flying northeast across the Libau Marsh near Colonel Sulli- 

 van's lodge, while at the same time, others of the same kind were flying 

 northwest. A very interesting split in the migration of Canada Geese north 

 along the Red River was described to me by J. W. Baldock. Near the town 



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