THE MIGRATION OF BIRDS 



Perhaps another division should be made for the 

 interesting " casual vagrants " who occasionally 

 turn up in a country far off their normal range. 

 The American kildeer plover shot in Aberdeenshire 

 in 1867 is a good instance. 



The migration of birds is a seasonal flitting, and 

 there is a contrast between the autumn and the 

 spring movements. The autumn migration, on the 

 whole southwards, is less hurried than the return 

 migration in spring. There is often a good deal of 

 fuss and dallying before the autumn migrants get 

 fairly under way. They make trial journeys and 

 may begin their pilgrimage with short stages. The 

 young birds are said to get restless first ; the old 

 males are said to linger longest. It may be that the 

 adults are kept back by the need of rest after their 

 family cares, and also by a moult after which the 

 feathers damaged by the summer's wear and tear 

 are replaced. 



In spring, on the other hand, the movement is 

 keener and more rapid. The full-grown males seem 

 usually to take the lead ; then follow the full-grown 

 females ; the younger birds, who will not breed for 

 a season or two, bring up the rear. Thus the spring 

 order is the reverse of the autumn order. There is 

 some evidence, also, that the spring journey is more 

 direct than the autumn journey. Short cuts are 

 found and haste is evident. It is interesting to 

 notice Audubon's observation in reference to the 

 American rice bird, that it flies in spring by night, 

 and in autumn by day. 



Another general fact in regard to migration is its 

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