258 FIELD ZOOLOGY. 



scavengers. This is a service little appreciated. Along 

 bay, lake, pond, river, or stream, flies, moths, beetles, and 

 other insects frequently fall into the water and are drowned, 

 and their bodies lodge in the shallows or are swept down 

 stream. One hardly suspects this fact till on some lazy 

 summer afternoon, he lies quiet and motionless in the 

 shadows and sees over and over again about him the 

 enactment of this tiny tragedy, of insect fall and quick 

 pursuit by the bird. 



Hawks and owls as a group, with the few exceptions 

 of Cooper's Hawk, the Sharp-shinned, and the Goshawk, 

 are of large benefit to farmers in getting rid of the small 

 rodents so destructive to growing crops. No one knows 

 this so well as the cattlemen on the western plains, who 

 regard the hawks as valuable allies. It is difficult to 

 overthrow an age-old belief, and to convince people 

 without repeated and strongly impressed proof ; but every 

 student of birds, and everyone interested in crops and 

 their dependence upon different birds in different parts 

 of the world, ought to do his utmost to correct the prej- 

 udice against the family of hawks. The reprobates of 

 the tribe have just been mentioned ; but there are plenty of 

 beneficial hawks whose service should be a matter of 

 gratitude, on the part of farmers especially. 



Analysis of numerous stomachs of hawks, the most 

 conclusive way of determining a bird's habitual diet, 

 reveals the facts that squash bugs, grasshoppers, and large 

 caterpillars are freely eaten, while the marsh hawk is a 

 valuable destroyer of field mice and ground squirrels. 

 The sparrow hawk is a valuable ally in getting rid of 

 grasshoppers; the adult red-tails eat largely insects and 

 mice; and the young of the hawk tribes are more exclu- 

 sively insectivorous than are the adults. 



