THE FOOD OF SOME WILD BIRDS 257 



At the opposite end of the scale, as performing less 

 service than harm to man, are the Wood-pigeon, 62 per cent, 

 of whose food consists of cultivated crops, and the House- 

 sparrow, of which the food in agricultural districts contains 

 75 per cent, of grain. Regarding the latter Dr Collinge 

 writes with no uncertainty : " It has become one of the worst 

 pests we have, and at present the attitude of all farmers must 

 be one of extermination." Yet 



" In men whom men condemn as ill 

 I find so much of goodness still," 



and Dr Collinge could not have brought forward more 

 convincing evidence of the Sparrow's usefulness than his 

 diagram of its food in fruit-growing districts, where 35 

 per cent, of injurious insects in addition to 20 per cent, of 

 weed seeds, to say nothing of the 88 per cent, of injurious 

 insects consumed by the nestlings, definitely turn the scale 

 in such areas in favour of the outrageous Sparrow. The 

 contrast suggested by Dr Collinge's consideration of the 

 Sparrow in two distinct types of areas affords a strong 

 argument for the limitation of any one study of the food 

 of birds to a single area of definite agricultural or horti- 

 cultural facies. 



Of the other birds dealt with in the paper, the Rook and 

 the Sparrow-hawk stand near the border-line between good 

 and evil. It is deplorable that the food of the latter should 

 consist, to the extent of 42-5 per cent., of game-birds, poultry, 

 and insectivorous birds, but on the other hand, injurious 

 insects account for 15 per cent, and Sparrows, Blackbirds, 

 and Wood-pigeons for 23-5 per cent. A decision in such a 

 case can be no easy matter, but Dr Collinge is " of opinion 

 that the injuries the bird inflicts are considerably in excess 

 of the benefits it confers," and in consequence he advises that 

 all protection be withheld for the time being from the 

 species. The detailed computation of the food of the Rook 

 shows, as field evidence has always done, that the bird is 

 likely to be a subject of controversy ; for it is a question 

 whether the 13-4 per cent, of potatoes and roots and the 35-1,- 

 per cent, of cereals are not more than counterbalanced by the 



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