THE BIRDS' AIR LINE 



travel southeastward and then join in the jour- 

 neys of eastern birds. 



This is the route the little Blackpoll Warbler 

 follows in his seven-thousand-mile journey from 

 Alaska to northern South America. There is no 

 question about the straightness of his air line! 

 He lays his course directly across Cuba to 

 Jamaica and from Jamaica to Colombia in north- 

 ern South America. That is a journey anyone 

 might be proud of. What a marvel it is 

 that it should be made regularly twice each 

 year by a creature only five and a half inches 

 long! 



In their travels across the United States, birds 

 seem to follow coast lines and river valleys. 

 They must pass through a country which will 

 supply them with food when they pause to rest. 

 Even if they fly over us we cannot expect them to 

 stop if we can offer them nothing to eat. 



Near my home at Englewood, New Jersey, is 

 a small ice pond. Sometimes the dam which 

 makes it is raised and the water runs out. This 

 happened once in August, a season when many 



