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THE NATIONAL GEOGRAPHIC MAGAZINE 



Phutograph t^y Thomas Lileyler 



SOME OF man's most USIU'*UI< FEATriKRED FRIICNDS 



Gulls perform very real services as scavengers, keeping many a beach clear of dead fish 

 and other refuse. They wander far up our rivers and even breed in large numbers on the lakes 

 of the interior. 



his kind appeared no more until spots of 

 bare ground became visible. 



MILLIONS MIGRATL AS SEASONS CHANGE 



The bird life of the United States is 

 believed to total more than four billion in- 

 dividuals. This means that many hundred 

 millions of migrants move north and 

 south with the changing seasons. Though 

 many go by day and may be seen by all 

 who take the trouble to observe, vast 

 numbers also pass by night. 



During the height of the spring migra- 

 tion, those whose ears are attuned to 

 Nature's voices may hear mysterious 

 notes overhead, many of which may be 

 recognized. They mark the course of 

 winged travelers exidting in springtime 

 vigor and approaching nuptials in the 

 haunts which they seek toward the top 

 of the world. Telescopes held on the 

 moon at that time often reveal their 

 silhouettes as they cross its face. 



In autumn the throng moves southward 

 over a longer period, and the travelers 

 wear the soberer garb of everyday life. 



Though it has been plain that migrat- 

 ing species, in general, move north and 



south — the movements of some covering 

 nearly or quite the entire length of the 

 continent — yet only vague information on 

 the subject has been available, since it was 

 impossible to determine the movements 

 of individuals. Through bird banding a 

 method is now developed that will not 

 only tell us where individual birds wan- 

 der, but will enable us to trace their 

 routes and determine the exact areas 

 where they go in the north to rear their 

 young or in the south to winter. 



We may also learn something concern- 

 ing the strange, sporadic occurrence of 

 l)irds in ]iarts of the world far distant 

 from their homes. 



Such wandering individuals are prob- 

 ably much more numerous than we sus- 

 ])ect. This is indicated by the repeated 

 occurrences of Robins, Bobolinks, and 

 other American birds in England, and 

 even on Helgoland, that insignificant islet 

 in the North Sea where so many visitors 

 from distant regions have lieen found. St. 

 Paul Island, the largest of the small Pribi- 

 lof Islands, in Bering Sea, appears to be 

 another landing place for lost birds, judg- 

 ing from the number of stragglers from 



