MIGRATIONS OF WATERFOWL 



pletely lacking in sunglow, and in the urgency of their homeward migration, 

 a great part of the spring transients go through while there is enough light 

 in the sky for us to see their passage. Most conspicuous of the daytime 

 travelers are the four species of blackbirds, the Bronzed Grackle, all hawks, 

 swallows, the Crow and Bluejay and the Flicker, which carry on the whole 

 of their migration with sunlight in the sky. Many others among the shore- 

 birds, thrushes, finches, and warblers are conspicuous daytime travelers, 

 although they also migrate heavily after dark. 



In all these kinds I have mentioned, the main source of arrival is the 

 southeast; and in some species, such as the Flicker, the total of the season's 

 passage apparently comes from that direction. In the blackbirds, some reach 

 Delta from the straight south, and several times I have followed a flock for 

 miles as I drove along a north-south highway; but most travel across the 

 prairie at the same southeast-northwest angle. They come on a broad front. 

 On the morning of April 27, 1951, Colonel Arthur Sullivan, Premier Douglas 

 L. Campbell, and I encountered twenty-five flocks of blackbirds along the 

 forty-five miles between the outskirts of Winnipeg and Portage la Prairie as 

 we drove westward along highway No. 1. The flocks were rather evenly scat- 

 tered along the way and most of them were just departing from the wooded 

 river valley, striking northwest across the White Horse Plains. At the same 

 time we saw Flickers everywhere along this course, in trees or starting out 

 to the northwest across the bald prairie. On other days I have seen the 

 movement of blackbirds and Flickers evenly spread all the way east to 

 Libau, Manitoba, a distance of about sixty-five miles, and at other times to 

 Roseneath, seventy miles west of Delta. 



When these hawks, blackbirds, Crows, and Flickers cross the marsh and 

 arrive at the edge of Lake Manitoba, they do not continue over the lake, as 

 the ducks do, but turn to follow the shoreline westward. There is thus a con- 

 centrated lane of travel along the wooded ridge, with flocks of blackbirds 

 sometimes going over the village of Delta at the rate of two or three flocks 

 a minute. On the morning of April 25, 1951, in a flight lasting from about 

 6:00 to 9:30 a.m., I estimated that at least 50,000 blackbirds flew over the 

 village. 



In their travels the blackbirds have an air speed of about twenty-five 

 miles per hour, and the Flicker and the Crow an air speed of about the same. 

 I have seen blackbirds travel at elevations ranging from a few feet above the 

 ground to approximately 500 feet. Most going past Delta are between 25 



* Red-winged, Brewers, Rusty, and Yellow-headed Blackbirds. 



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