THE FOOD OP BIRDS IN INDIA. 



the sole food of that bird. At the latter time the damage is done, 

 while if some caterpillars are eaten in the early broods, for every 

 one eaten then, thousands, that would otherwise have appeared 

 later in the year, are non-existent. It is, therefore, obvious that a 

 bird that feeds habitually on injurious insects is of far more econo- 

 mic value than another bird, whose diet varies according to food 

 supply. Every bird's food must vary somewhat according to food 

 supply, and we, therefore, speak in the sense applicable to the above. 



One often hears that great authorities on birds refuse to give 

 an opinion as to whether partially insectivorous or omnivorous 

 birds should be encouraged and protected, and with very good 

 reason. Birds can in some cases increase with extraordinary rapid- 

 ity, and if encouraged it is surmised that insect -life- of which there 

 is abundance in India at present would rapidly decrease ; birds 

 being unable to find food elsewhere, would then undoubtedly attack 

 crops. This theory might very possibly prove correct, but until it 

 is put into practice no one can foretell definitely what would happen. 

 In considering this question the following points should always be 

 borne in mind. The theory advanced above can have no applica- 

 tion to birds not indigenous to the country, or rather to birds which 

 may have been recently imported. Now a bird provided that it is 

 a resident species is undoubtedly a far easier thing to destroy than 

 many insects, in spite of the fact that most insects destroyed by bird? 

 are also those most readily destroyed by science applied in a prac- 

 tical manner, and should the bird prove the theory advanced above, 

 that bird could be checked after its beneficial work was done. With 

 migratory species it is a very different matter. Should birds be 

 protected and encouraged, they may exterminate certain insects, 

 amongst which some crop pests would certainly occur, and as likely 

 as not some parasitic insects as well. But enough is now known 

 and more will shortly be known about importation of insect para- 

 sites to render that importation a safer procedure and more reliable 

 than formerly. 



In considering the whole question of economic ornithology 

 every point for and against the bird in question must be carefully 



