Society for the Protection of Birds.—No. 47. 
ESSAY 
ON 
The Economic Value of Birds. 
To which was awarded the Second Prize in the Society's 
Essay Competition , 1902-1903. 
I N England the study of the food of birds, and the part which 
they play in the economy of nature, has, unfortunately been 
much neglected. As a rule, the only information which can be 
gleaned from English writers on the subject is, with but few ex¬ 
ceptions, of an unsatisfactory nature. In far too many cases it is 
obviously of an imperfect character, and though observations of 
the greatest importance are to be found scattered here and there 
among the pages of ornithological works and natural history 
journals, their value is seriously discounted by the unsystematic 
way in which they have been recorded, and, as a rule, the want of 
any means of determining the proportions of the varying elements 
of which a bird’s food consists. With the possible exception of 
certain rare instances of habits acquired under unnatural con¬ 
ditions (such as the sheep-killing propensities developed by the 
Kea in New Zealand*), it may be laid down as an axiom that no 
bird is altogether harmful to man. In almost every case, the only 
real question at issue is whether the good effected outweighs the 
evil, or vice versa. Under these circumstances, the casual notes 
and observations on the food of our British birds which are to be 
found in most works on the subject are insufficient for our purpose. 
What we really want to know is the ascertained percentage of good 
and evil effected during the year by each species of bird whose 
character has been called in question. 
* Cf. “ Zoologist,” 1881, p. 290, etc. 
