10 INTRODUCTION. 



wholly harmful; and not only is the farmer boy encouraged to kill 

 every hawk and owl about the farm and to destroy its nest, but the 

 powers of the law are invoked to offer the incentive of bounties for 

 hawks' and owls' heads. 



If this widespread belief in the harmful propensities of these birds 

 is correct, then their wholesale destruction is laudable. If, however, 

 such belief is erroneous, the consequences are mischievous enough. 



It is important to observe that all the rapacious birds are slow breed- 

 ers, and, contrary to popular belief, there is no good evidence that any 

 of them have two broods a year, though of course if the first set of eggs 

 is lost another one will be deposited. There is every reason why they 

 should not raise more than one brood, for notwithstanding the fact that 

 they breed very early in the year, the young grow slowly and remain 

 a long time in the nest. Hence the tax upon the parent birds to secure 

 enough food to satisfy the enormous appetites of their slow-growing 

 progeny is very great, probably twice that made ux)on the members of 

 any other order of land birds. 



State laws, therefore, passed for the destruction of hawk s and owls, 

 and offering a bounty on their heads, are very effective, either for good 

 or evil. One of the counties of Pennsylvania paid out in a year over 

 $5,000 for scalps of birds of prey. In the light of the foregoing facts it 

 will readily be understood how long a time it will take to replace these 

 birds, whose destruction cost the State of Pennsylvania so much 

 money, in case their services are wanted. There is no doubt that this 

 State and others which have passed similar laws have made a serious 

 mistake; for it is indisputable that the opinion about hawks and owls, 

 so widespread and popular, is not well founded; and it is the pur- 

 pose of this bulletin to set forth the results of many years' observations 

 with the view of dispelling the popular illusion regarding the destruc- 

 tiveness of hawks and owls as a class. It may be stated with confi- 

 dence — 



(1) That owls are among the most beneficial of all birds, inflictin g 

 very little damage upon the poulterer and conferring vast benefits 

 upon the farmer. The relations which owls bear to agriculture are 

 peculiar and important. Their eyesight, unlike that of hawks, which 

 hunt by day, is by no means so defective in daylight as popularly sup- 

 posed, but is keenest in the early hours of evening and in early morning. 

 Hunting thus in dim light, their food consists largely of those ani- 

 mals which hawks do not trouble at all, or destroy only in small 

 numbers. The work of owls thus supplements that of hawks and 

 materially assists in preventing an undue increase of many obnoxious 

 rodents. Again, though owls are somewhat migratory they are far 

 less so as a class than hawks, and hence in winter, when the latter 

 have left the Northern States for warmer climes, they remain at home 

 and carry on their incessant warfare against injurious rodents. 



(2) That all hawks, with j)ossibly one or two excej)tions, are to some 

 extent beneficial to the farmer. 



