Birds in Relation to Agriculture in New York State 1781 



grosbeaks were fed 426 times, and wrens 600 times. Experiments have 

 been performed with young crows in order to determine the exact amount 

 of food reqmred by them in maintaining strength and growth, and it has 

 been discovered that they lose weight unless given food equal to one half 

 their own weight every day. Young robins have been known to eat 

 their full weight of earthworms in a day. 



When we stop to consider these facts we begin to reaHze what efficient 

 machines the birds are for the destruction of insects. They maintain a 

 natural balance and check the undue increase of any species. But they 

 work so quietly that few persons realize their value until for one reason 

 or another their control is suddenly removed, and some insect pest, such 

 as the grasshoppers and army worms during the current year, spreads over 

 the land. Much more conspicuous is the damage that a few individuals 

 occasionally do in the poultry yard or in the cherry orchard. The news 

 of such a loss from birds becomes greatly exaggerated, and overrides com- 

 pletely the really tremendous saving that the birds have more quietly 

 brought about. 



FOOD HABITS OF BIRDS 



From the fishes that dart through the streams, and the grubs that bur- 

 row in the soil, to the insects that flit over the top of the forest, there is 

 scarcely a plant or an animal substance that does not furnish the food of 

 some group of birds. .The water plants and mollusks that grow at the 

 bottom of the lake are not safe from ducks ; fishes are pursued through the 

 dark waters by loons and grebes, or speared from above by herons and 

 kingfishers; the grubs and worms in the soil are probed for by the snipe 

 and the woodcock, or seized when they come to the surface by blackbirds 

 and thrushes; the cutworms and beetles that crawl on the ground are 

 caught by larks and sparrows ; the insects that mount into the bushes and 

 trees are seized by the hosts of smaller vireos and warblers, while those 

 that hide within the trunks and branches are drilled out by the wood- 

 peckers. If they have wings they are pursued by the flycatchers and 

 swallows, so that none of them are safe. It would obviously be impossible 

 to treat thoroughly, in these few pages, all the varied foods of .birds, nor 

 is it necessary if we bear in mind our need of all kinds of birds to hold in 

 check the great variety of foes that the agriculturist has to meet. Rather 

 wiU we outline the various groups of birds according to their food, and 

 emphasize only those that have the most immediate bearing on agricrd- 

 ture in New York State. 



The general nature of a bird's food can frequently be determined by 

 the general structure of the bird itself. The varied proportions of wing 

 and body, the size and shape of bill and feet, which in addition to their 

 colors give birds their great variety, are due largely to the differences in 

 their food and in their methods of securing it. 



