BIRDS 



299 



of birds once believed to harm crops really perform a service to 

 the farmer by killing injurious insects. Even the much mali<,med 

 crow lives to a large extent upon insects. During the entire year, 

 the crow eats about 25 per cent insect food and 29 per cent grain! 

 In May, when the grain is sprout- 

 ing, the crow is a pest, but he 

 makes up for it during the re- 

 mainder of the summer by eat- 

 ing harmful insects. The robin, 

 whose presence in the cherry tree 

 we resent, during the rest of the 

 summer does untold good by feed- 

 ing upon noxious insects. Birds, 

 as a rule, feed upon the sub- 

 stances which are most abundant 

 around them at the time. The 

 following quotation from I. P. 

 Trimble, A Treatise on the Insect 

 Enemies of Fruit and Shade Trees, 

 bears out this statement: "On 

 the fifth of May, 1864, . . . seven 

 different birds . . . had been 

 feeding freely upon small beetles. 

 . . . There was a great flight of 

 beetles that day; the atmosphere was teeming with them. A few 

 days after, the air was filled with Ephemera flies and the same 

 species of birds were then feeding upon them." ^ 



^ During the outbreak of Rocky Mountain locusts in Nebraska in 1874-1877, 

 Professor Samuel Aughey saw a long-billed marsli wren carry tliirty locusts to her 

 young in an hour. At this rate, for seven hours a day, a brood would consume 210 

 locusts per day, and the passerine birds of the eastern half of \cbraska, allowing 

 only twenty broods to the square mile, would destroy daily 1()2,771,0(M) of tin* 

 pests. The average locust weighs about fifteen grains, and is capable each day of 

 consuming its own weight of standing forage crops, which at SIO per ton would be 

 worth $1,743.97. This case may serve as an illustration of the vast good that is 

 done every year by the destruction of insect pests fed to nestling birds. And it 

 should be remembered that the nesting season is also that when the destruction of 

 injurious insects is most needed; that is, at the period of greatest agricultural 

 activity and before the parasitic insects can be depended on to reduce the pests. 

 The encouragement of birds to nest on the farm and tiie tliscourageinent of nest 

 robbing are therefore more than mere matters of sentiment ; they return an actual 

 cash equivalent, and have a definite bearing on the success or failure of the crops. — 

 Year Book of the Department of Agriculture. 



AMERICAN CROW 



EN0LI8H SPAmOW 



Food of some common birds. 



