26 



JOURNAL OF THE WILD BIRD INVESTIGATION SOCIETY. 



an amount per year, and of this total bulk a 

 certain percentage consists of food that is 

 conferring a direct benefit upon agriculture, a 

 further percentage is a direct injury, and the 

 remainder is of a neutral nature. 



Such information at once places before the 

 farmer the exact relationship which exists 

 between the particular species of bird and his 

 crops. Thus supposing we state that a cer- 

 tain species consumes lolbs. of food per 3'ear, 

 which consists of 50 per cent, of injurious 

 insects, 5 per cent, of neutral insects, 10 per 

 cent, of slugs and snails, 13 per cent, of 

 cereals and cultivated roots, and 20 per cent, 

 of the seeds of wild grasses, weeds, etc. Such 

 an analysis enables the farmer to immediately 

 appreciate the damage this species commits 

 and the benefits it confers. Of the total bulk 

 of food, he can now see that it is composed of 

 the following proportions: — 



Injurious Insects 

 Slugs and Snails 



Neutral Insects .. 



... 5 lbs. 



... o-S „ 



Beneficial 6 • o 



Neutral 2 ■ 8 



Grass and Weed Seeds ... 2'o ,, 



Cereals and Roots ... 1-8 ,, Injurious i-8 



In other words, 6 lbs. of the bird's food is a 

 direct benefit to the farmer, consisting as it 

 does of insects and other forms of animal life, 

 which unless destroyed would quickly ruin 

 his crops; albs. 8oz. of the food is neutral, 

 and the actual damage is a loss per bird of 

 24 ounces of cereals and roots. 



Now the question arises: "Is it to ihe 

 farmer's advantage to lose 24 ounces of 

 cereals, etc., in' order to destrov 6 pounds of 

 injurious insects, etc.?" In other words, 



Does the destruction of the injurious insects 

 compensate the farmer for the loss of the 

 cereals and roots? " Our answer is emphati- 

 cally Yes, for by no other means could he 

 remove such a devastating army at anything 

 like the cost. Indeed, were it not for the 

 ceaseless activity of the " winged wardens " 



23-9%) 

 3-2 }- Beneficial 28-5% 

 1-4 ) 



of the farm, it would be very difficult to reap 

 a crop at all. 



Once having established a definite and 

 reliable method of estimating the food of a 

 bird, it is comparatively simple to decide 

 upon those species that are beneficial and 

 those which are injurious. Let us examine 

 the records for two species that have been 

 subjected to considerable criticism during the 

 past few years, viz., the Rook and the 

 Pheasant. 



Of the total bulk of food consumed by the 

 rook per year, 59 per cent, consists of animal 

 matter and 41 per cent, of vegetable matter. 

 The several items and their percentages are 

 as follows : — 

 Injurious Insects 

 Slugs 

 Sparrows, etc. 



Cereals ... 35-1 1 



Potatoes and Roots ... 13-4 Injurious 52-0% 



Beneficial Insects ... 3-5 I 



W'ildFruits&W'eedSeeds 4-4 | 



Moll. Vegetable matter 6-i :_ Neutral iq-s"/ 



Neutral Insects ... 4-6 ! ^^eu^rai 195/0 



Earthworms ... ... 4-4 ) 



A little more than half of the total bulk of 

 the food is an injury to the farmer, and 28.5 

 per cent, is the compensating balance. Now, 

 in the case of the rook we know that they are 

 exceedingly plentiful, their numbers have 

 rapidly increased of recent years, further, we 

 know that with the increa.se of the starling 

 there is a keen struggle for existence between 

 these two species. The food supply being 

 insufficient, the rook has taken to feeding 

 upon cereals and cultivated roots, and the 

 starlings upon cereals and cultivated fruits. 

 In all probability, i.e., so long as the rook 

 and the starling population remain so great, 

 these items in their respective diets will tend 

 to increase rather than diminish. We must 

 therefore place the rook under the category of 

 injurious birds. 



The Pheasant is another bird that has been 

 accused of doing great harm to standing 



