The English Sparrow as a Pest 



By Ned Dearborn 



The English sparrow was introduced into America a little more than 60 

 years ago, and is now distributed over nearly all of the United States and 

 southern Canada. This rapid dissemination is a result of the bird's hardiness, 

 extraordinary fecundity, diversity of food, aggressive disposition, and almost 

 complete immunity from natural enemies. 



The English sparrow among birds, like the rat among mammals, is cunning, 

 destructive, and filthy. Its natural diet consists of seeds, but it eats a great 

 variety of other foods. While much of its fare consists of waste material from 

 the streets, in autumn and winter it consumes quantities of weed seed and in 

 summer numerous insects. The destruction of weed seed should undeniably 

 count in the sparrow's favor. Its record as to insects in most localities is no 

 so clear. In exceptional cases it has been found very useful as a destroyer 

 of insect pests. For example, during a recent investigation by this bureau of 

 birds that destroy the alfalfa weevil in northern Utah, English sparrows were 

 feeding their nestlings largely on weevil larvae and cutworms, both of which are 

 very injurious to alfalfa. In this case the sparrows, attracted by grain in the 

 fields and poultry runs and by the excellent nest sites afforded by the thatched 

 roofs of many farm buildings, had left the city and taken up their abode in the 

 country where the weevil outbreak subsequently occurred. Unfortunately, how- 

 ever, farmers can rarely expect such aid against their insect foes. Wherever 

 this bird proves useful, however, it is entitled to protection and encouragement 

 in proportion to its net value. 



Under normal conditions its choice of insects is often unfavorable. Out 

 of 522 English sparrow stomachs examined by the Biological Survey, 47 con- 

 tained noxious insects, 50 held beneficial insects, and 31 contained insects of 

 little or no importance. The bulletin just referred to shows conclusively that, 

 aside from the destruction of weed seed, there is, in general, very little to be 

 said in the sparrow's favor. 



On the other hand much is to be said against the bird. It destroys fruit, 

 as cherries, grapes, pears and peaches. It also destroys buds and flowers of 

 cultivated trees, shrubs and vines. In the garden it eats seeds as they ripen, 

 and nips off tender young vegetables, especially peas and lettuce, as they appear 

 above ground. It damages wheat and other grains, whether newly sown, ripen- 

 ing, or in shocks. As a flock of 50 sparrows requires daily the equivalent of a 

 quart of wheat, the annual loss caused by these birds throughout the country 

 is very great. It reduces the number of some of our most useful and attractive 

 native birds, as bluebirds, house wrens, purple martins, tree swallows, cliflf 

 swallows, and barn swallows, by destroying their eggs and young and by usurping 

 nesting places. It attacks other familiar species, as the robin, wren, red-eyed 

 vireo, catbird and mocking bird, causing them to desert parks and shady streets 

 of towns. Unlike our native birds whose place it usurps, it has no song, but is 



494 



