IS so very great that it is no exaggeration to say that practically all the waking 

 hours of our warblers, from daylight to dark, are devoted to food-getting. What 

 this never-ceasing industry means when translated into tons-weight of insects, it 

 is impossible even to guess, but the practical result of the work of our warblers 

 and other insectivorous birds is that we still have our forests, and shall continue 

 to have them so long as we encourage and protect the birds. 



In the case of orchards and shade trees, there are other means at our dis- 

 posal of controlHng the insect enemy, notably the use of sprays. Sprays are 

 very important, since birds are too few in number immediately to control insect 

 outbreaks, especially nowadays, when the number of destructive native insects 

 has been so greatly increased by importations from all quarters of the globe. 

 But for the preservation of our forests we must rely largely upon our birds, 

 since the use of sprays or of other agencies over our vast woodland tracts would 

 be too expensive, even were it not quite impracticable for many other reasons. 



MEANS OF INCREASING THE NUMBER OF WARBLERS 



Insects are very numerous, and there is reason to believe that much benefit 

 would result if we could multiply the present number of their enemies — the birds. 

 The erection of bird boxes and shelters is an easy way to increase the number of 

 certain species of birds, like swallows and chickadees. Unfortunately, with few 

 exceptions, our warblers do not build their nests in cavities, and hence can not 

 be induced to occupy bird boxes. 



Many of them, however, nest in bushes, vines and shrubbery, and by planting 

 clumps of these near houses something can be done toward increasing the number 

 of certain species, as the yellow warbler and the redstart. Because our warblers 

 are chiefly insectivorous, their food habits bar them from the usual bird 1un-h- 

 counter in times of hard storms. 



During migration, warblers are peculiarly exposed to the danger of prowling 

 cats. Many species feed close to or even on the ground, and then they are so 

 much concerned with their own business that any tabby, however old and lazy, is 

 equal to catching one or more individuals daily. The bird lover can do good 

 service by summarily disposing of vagrant cats, which, during migration, work 

 havoc in the ranks of our small birds. 



They can also restrain the pernicious activities of their own pets, for these, 

 however well fed, are still subject to the predatory instincts of their wild ances- 

 try, which impel them to stalk a live bird with all the zeal and cunning of their 

 forebears. 



PLUMAGES OF WARBLERS 



Little difficulty is experienced, even by the tyro, in distinguishing warblers 

 from other birds, but to recognize the several species is not so easy, particularly 

 as the adult males and females of many species are markedly dissimilar, while 

 the young, both in the first and second plumages, often differ from the adults. 

 So far as possible the various plumages are shown in the illustrations of the 

 artist, which are so admirable as to do away with the need of descriptive text. 

 All are approximately one-half life size. 



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