Part II.] NATURAL ENEMIES OF BIRDS. 263 



The following from Dr. Palmer's summary shows tersely the 

 principal objections to any system of premiums for the de- 

 struction of animals: — 



Objections to the bounty system may be grouped under four main 

 heads: (a) expense, which is usually out of all proportion to the benefit 

 gained, and may be greater than the county or State can afford; (6) im- 

 possibility of maintaining bounties in all parts of an animal's range for 

 any length of time; (c) impossibility of maintaining equal rates in all 

 States; (d) impossibility of preventing payments for animals imported 

 from other States, for counterfeit scalps or for animals raised especially for 

 the bounty. These objections have never been satisfactorily overcome, 

 and most laws have failed through one or another of these causes.^ 



CONCLUSION. 



In recapitulating, it may be said that this bulletin shows 

 that (1) natural enemies of birds are necessary and desirable, 

 as they tend to maintain within proper bounds the numbers 

 of the species on which they prey; (2) organized attempts to 

 increase the numbers of birds over large areas by destroying 

 indiscriminately all natural enemies are undesirable; (3) under 

 certain circumstances enemies which have been able to adapt 

 themselves to man and his works and have become unduly 

 numerous may require reduction in numbers; (4) individuals 

 of useful species which may become particularly destructive 

 should be eliminated; (5) self-interest on the part of the people 

 most concerned eventually will bring about such reduction of 

 predatory animals as is needed without the stimulus of bounty 

 laws, which in most cases are pernicious and which if enacted at 

 all should be directed only against the larger predatory animals 

 or those which are dangerous to human life or exceedingly de- 

 structive to domestic animals or crops. 



1 Palmer, T. S.; Extermination of Noxious Animals by Bounties, Yearbook, U. S. Dept. of 

 Agr., 1896, p. 68. 



