Bird Migration. 



UNTIL the last few years it was generally believed 

 by naturalists and ornithologists alike that in 

 migration the older or parent birds preceded the 

 younger ones on their long flight, and even eminent 

 authorities on bird life fell into this error. 



Expressed in the simplest language, the incontestable 

 result of all the numerous phenomena as they came under 

 notice in a certain North Sea observatory is as follows : 



(1) That under normal conditions in the case of over 



three hundred specimens, with the exception of a 

 single one, the autumn migration is initiated by 

 the young birds from about six to eight weeks after 

 leaving their nests. 



(2) That the parents of these do not follow till one or 



two months later. 



(3) That of these old birds the most handsome old males 



are the last to set out on the migratory journey. 

 The only exception to this rule, as previously mentioned, 

 is the cuckoo, and this for reasons easy to divine. Plumage 

 enters a great deal into the art of ascertaining the old from 

 the young whilst on the wing. The marking and colour of 

 such birds as the starling would at once identify the age. 

 The blackbird, again, is another species in the case of 

 which the time of migration in respect to age and sex can 

 be determined with the utmost exactness by reason of the 

 difference between their early and adult plumages. The 

 young reddish-brown birds with which the migration com- 

 mences rarely make their appearance before, say, October ; 

 the old black males defer their arrival till November, and 

 of these latter again the last to arrive, some weeks later, 

 are the beautiful glossy blackbirds with orange-yellow 

 bills. 



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