TEACHING BIRD STUDY 



able studies that could have claimed their atten- 

 tion. 



For many years the United States Department of 

 Agriculture has been employing trained naturalists to 

 give their time to the investigation of the damage 

 done to growing crops by the insect hosts that in- 

 fest fields and forests. These and other experts 

 have come forward with astounding statements re- 

 garding the destructiveness of birds to insects. We 

 are told, too, that' each bird is virtually a living dy- 

 namo of energy; that its heart beats twice as fast as 

 the human heart; and that the normal temperature 

 of its blood registers over a hundred degrees. It 

 is a simple fact of biology, therefore, that a tremen- 

 dous amount of nourishing food is necessary for 

 the bird's existence. Vast quantities of insects are 

 needed for this purpose. 



Some time ago a New England gentleman became 



so impressed by the frequency with which a pair of 



Robins visited their nest with food for the young that 



he determined to learn more about the food-consum- 



[241 ] 



