Long journeys are carried out in the absence of the sun or other celestial guides. 



Williams and Kalmbach, 1943; McCabe, 1947; Foley, 1954b) there can be 

 no inborn awareness in waterfowl of the direction of home. The course 

 of homeward migration must be founded on experience of the world. 



This discussion is not presented as an explanation of migrational orien- 

 tation, but merely attempts to organize the problem, especially with respect 

 to waterfowl. The evidence at hand suggests that adult waterfowl travel 

 as experienced birds over a familiar range. By reference to the sun, as 

 to a compass, or to environmental patterns, like those presented by waves, 

 they may hold a direct course for some distance without visual reference 

 to a familiar landscape. The studies of Matthews and Kramer (yet to be 

 repeated with waterfowl) suggest that the sun may serve as the cue to 

 the direction of home when the bird is displaced from familiar surround- 

 ings, but that such awareness hinges on the bird's distance from home. 

 Long journeys are carried out in the absence of the sun or other celestial 



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