ECONOMIC VALUE OF OUR BIRDS 55 



There are five groups of birds of special value to 

 us because of the insects they consume; and they 

 will be named in what we believe to be the order of 

 their importance. They are: 



The song-birds, 



The tree-climbers, 



The swallows and swifts, 



The shore-birds, 



The grouse and quail. 



To these are to be added a number of miscella- 

 neous species of special value, such as the goat- 

 suckers, certain small hawks, and a few ducks, 

 egrets, herons and ibises. 



The Song-Birds of themselves alone form a 

 mighty host. The great family of Warblers heads 

 the list, both in number of species and in static effi- 

 ciency. Except the humming-birds, they are the 

 smallest of the passerine order, and the forms and 

 colors of many of the species are so very inconspicu- 

 ous that only the sharp eye will notice their tiny 

 gray forms as they quietly flit or glide, a yard at 

 each move, through the foliage that they are comb- 

 ing out. Their work is mostly in the tops of the 

 trees. The high- water mark in insect destruction 

 is reached by these birds. Bulletin No. 44 of the 

 Department of Agriculture gives the results of an 

 exhaustive examination of 3,398 warbler stomachs, 

 from seventeen species, and the result shows 95 

 per cent of insect food, mostly bad insects, too, 



