THE TRAVELS OF BIRDS 



it winters along the borders of the Antarctic 

 Continent The distance between its summer 

 and winter home is, therefore, about eleven thou- 

 sand miles. This means that one bird flies nearly 

 half-way around the earth and back each year. 

 This great journey is made by thousands of Arc- 

 tic Terns; but in spite of their numbers and the 

 length of their route, few ornithologists have 

 ever seen them traveling, and no one knows just 

 what route they follow. On the Atlantic coast 

 they have been seen south of their nesting ground- 

 but once. So it seems probable that, like the 

 Golden Plover, they migrate far out at sea. 



Professor Cooke calls attention to the interest- 

 ing fact that the Arctic Tern "has more hours of 

 daylight than any other animal on the globe. At 

 the northern nesting-site the midnight sun has 

 already appeared before the birds' arrival, and 

 it never sets during the entire stay at the breeding 

 grounds. During two months of their sojourn 

 in the Antarctic the birds do not .see a sunset, 

 and for the rest of the time the sun dips only a 

 little way below the horizon and broad daylight 

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