132 BIRD FRIENDS 



comprise about one fourth of their food. Among 

 these, however, are included a good many English 

 sparrows. 



The elements. Birds which spend the winter in 

 the northern United States may suffer severely 

 from the extreme cold and from lack of food on 

 account of the deep snows and the coating of ice 

 on trees that cover their food-supply. Many birds 

 perish every severe winter. The lack of food is one 

 of the chief reasons for this mortality. With plenty 

 of food birds can withstand very low temperatures, 

 but when they are only half fed, they easily suc- 

 cumb to the cold. 



Mortality during winter. In Massachusetts, Mr. 

 Forbush made a study of this matter during the 

 winter of 1903 to 1904 from reports received from 

 seventy-five correspondents. These reports showed 

 that during the first half of the winter, birds were 

 present in about their usual number, but as the 

 severity of the weather increased, the number of 

 birds began to decrease, till by the end of the winter 

 a very noticeable mortality was universally reported, 

 and many birds were found dying of cold and 

 hunger; and it was the opinion of those best fitted 

 to judge that most of the birds which usually win- 

 tered there were either starved or frozen. 



Among the greatest sufferers were the bob-white, 

 ruffed grouse, meadowlark, and flicker. In some 

 localities the bob-white was apparently entirely 



