THE NATIONAL GEOGRAPHIC MAGAZINE 



Photograph by Herbert K, Job 

 EOYAIv TERNS ARE GREGARIOUS BIRDS 



Breeding in great colonies off the South Atlantic coast and the shores of the Gulf of Mexico, 

 these birds nest so close together that it is difficult to walk through their breeding grounds 

 without treading on the eggs. 



breeding grounds there and to band as 

 many wild fowl as practicable. At the 

 same time he was to secure specimens of 

 the wild life of this unknown area. 



He proceeded early in the spring from 

 Washington to Fairlianks, Alaska. Im- 

 mediately after the ice broke up on the 

 rivers he went to Fort Yukon and en- 

 gaged an assistant with a motor boat. 

 Taking in tow a small barge loaded with 

 gasoline and other necessary supplies, 

 they set forth on the long trip into an un- 

 inhabited and little-known wilderness. 



The expedition was successful. In ad- 

 dition to gaining a great store of infor- 

 mation concerning the wild life of the 

 region, Mr. ]\Iurie placed bands on a 

 number of Geese and other birds. During 

 the succeeding autumn, three of the Geese 

 were taken in western Alberta, Idaho, and 

 Nevada, indicating a strong probability 

 that the wild fowl on the eastern border 

 of Alaska also winter west of the looth 

 meridian. 



Records from the banding of Ducks on 

 their breeding grounds and at their other 



great gathering places are yielding a har- 

 vest of valuable information. 



MIGRATORY WILD EOWE OF THE UNITED 

 STATES FORM TWO DISTINCT GROUPS 



The returns demonstrate that migra- 

 ^tory wild fowl in the United States, both 

 those breeding here and those which visit 

 us during the inigration and winter, are 

 separated into two well-marked groups: 

 those of the region extending frotn the 

 western Dakotas, western Kansas, and 

 western Texas to the Pacific, and those 

 which occur from the eastern Dakotas, 

 eastern Kansas, and eastern Texas to the 

 Atlantic. 



The two areas occupied bv these sepa- 

 rate groups correspond to the arid west- 

 ern region and to the more humid east- 

 ern part of the continent. The looth 

 meridian of longitude, a commonly ac- 

 cepted dividing line between the' arid 

 West and the more humid East, appears 

 to be well located for marking the bound- 

 ary between these areas. 



The accompanying map (see page ii6) 



