I04 The Birds of India. 
man in the form of insect destinction . Further, the adnit birds sometimes 
eat insects, and this they are likely to do whenever, from some canse or 
other, insects become unusually abundant, that is to say, precisely at the 
time when it is most important to man that liis little six-lef^ged foes should 
be devoured. As a set-off to this we must not forget the large amount of 
food grains that Sparrows devour. Moreover, were they less numerous, 
tlieir place might perhaps be taken by birds of more undoubted utility to 
man. Proba])ly the only method of arriving at the truth as regards the 
Sparrow is to exterminate him completely from a given localit)', and watch 
the results. This, I ])elieve, was done about forty years ago in Maine and 
Auxerre, with the result that almost every green leaf was destroyed by 
caterpillars in the following year. 
It is thus obvious that the determination of the economic value of 
some birds is not by any means a. simple matter. One thing is certain, and 
that is that no bird should be condemned as an enemy of man until a pro- 
longed and careful inquiry into its habits has been made. 
Running through the long list of Indian birds, we meet with some 
twent}' species which the economic ornithologist might perhaps class as 
"doubtful"; birds wliich certainly do devour food crops, and which must 
consequently be classed as foes, unless they render some service to man by 
way of compensation for the damage they do. These are the .Sparrows, the 
various species of Crow, the Rose-coloured Starling, some of the larger 
Finches, the Paroquets, the Doves an<l the Geese. 
Thk Crows. 
With the Sparrow we have already dealt. The Crows look upon the 
ripening crops as a feast prepared for their benefit. But grain forms quite 
an insignificant portion to their menu. They prefer tlie dustbin to the field, 
the town to the country. The corvi are a source of annoyance to man 
rather than an economic pest. They are useful if impertinent, scavengers, 
and undoubtedly destroy a large quantity of liarmful insects. Wlien a flight 
of locusts invades the land they, together with the Kites, render yeoman 
service to the husbandman. Even as a carcase attracts every vulture in 
the vicinity, so does a swarm of locusts bring together all the Crows of the 
locality. They leave their ordinary occupations to dance attendance upon 
the devastating host, seizing the insects with their claws and conveying 
them to the beak in mid air. Each crow devours locusts until threatened 
by death from a surfeit of food. 
In a sense Crows and other omnivorous birds are more useful than 
the purely insectivorous ones. Like the careful housewife, they live upon 
whatever happens to be in season. If it be locusts, they have locusts for 
breakfast, locusts for lunch, locusts for dinner. They, therefore, form a 
highly efficient corps of reservists, ready at a moment's notice to wage war 
against insect invaders. 
{To be Continued). 
