BIRD PROTECTION 389 



The American crow is a most deadly enemy to birds from the 

 size of the chipping sparrow to that of the night heron, ruffed 

 grouse, and the black duck, for it continually steals the eggs 

 and young of such birds and poultry. 



The well-known blue jay is destructive to the eggs of the 

 smaller birds, whose nests it robs systematically, and it has 

 frequently been seen to kill the young. The robin and other 

 larger birds will drive the jay away from their nests, but it 

 often succeeds in robbing -them by stealth. Vireos, warblers, 

 and sparrows it regards very little, and plunders their nests 

 without noticing their agonized cries. 



These birds, on the other hand, possess many useful traits. 

 Crows are valuable as grasshopper killers, and they are de- 

 structive to the gypsy moth. Jays eat the eggs of the tent- 

 caterpillar moth and the larvae of the gypsy moth and other 

 hairy caterpillars. 



The English Sparrow. The house or " English " sparrow 

 is the only one of the smaller birds that has repeatedly been 

 seen to destroy the nests of other birds, break their eggs, kill 

 their young, mob them, and drive them away from their homes. 

 It occupies the houses of bluebirds, martins, swallows, and 

 wrens, and the nests of barn swallows, cliff swallows, and bank 

 swallows, and by persistency and force of numbers drives the 

 owners away. 



Snakes. All the common snakes, except, perhaps, the little 

 green snake, eat birds and eggs. Birds exhibit great dread of 

 snakes, but the brown thrasher or the catbird will attack them 

 bravely in defense of their young. Some birds seem to be in- 

 capacitated by terror when a snake appears at the nest, and 

 are rendered incapable of any effectual defense. The common 

 black snake is the greatest enemy the birds have among native 

 snakes, for it climbs trees with the greatest ease, and is so 

 swift that it is able to catch young birds when they first leave 

 the nest and sometimes it strikes down an anxious parent. 



