122 NATURE-STUDY 



fish, frogs, toads, lizards, and snakes, while the larger birds 

 feed upon the smaller mammals and birds. Practically 

 all birds, even the little nectar-loving humming-bird, will 

 include insects on their bill of fare. Some birds, hke the 

 wrens, swallows, tanagers, swifts, nighthawks, warblers, and 

 vireos, are almost exclusively insectivorous. Thrushes, cat- 

 birds, robins, bluebirds, woodpeckers, chicadees, bluejays, 

 brown thrashers, cowbirds, cedar birds, orioles, brown 

 creepers, rose-breasted grosbeaks, kingbirds, phoebes, and 

 many shore birds feed chiefly upon insects. 



The Economic Value of Birds 



One thing should be emphasized in bird study, and that 

 is the "dollar and cents" value of birds. Man has a much 

 greater material interest in the birds than in their song and 

 beauty and lively ways. Our forefathers snared and shot 

 with bow and arrow the game birds, and we hunt them still. 

 Canvasback ducks, prairie chicken, and quail on toast are 

 delicacies of food. 



Long ago man captured the jungle fowl, wild goose, and 

 wild duck, and more recently the wild turkey, and has 

 domesticated them all. From them we have derived the 

 great variety of our domestic poultry. Poultry may be con- 

 sidered as domesticated game. The chicken industry alone 

 is very large in this country. The estimated production of 

 eggs in the United States is about 2,000 million dozen, which 

 at only fifteen cents a dozen would amount to $300,000,000. 

 To this should be added the dressed poultry of the meat 

 markets and the down of geese and ducks. 



The eggs of many wild birds, particularly seagulls, are 

 gathered in boat-loads on the sea cliffs and rocky isl- 



