ECONOMIC ORNITHOLOGY 267 



that already enormous damage has been done. Man has already 

 had to take, or tried to take, steps to check these increasing- 

 animals. When also a certain stage of excess has been reached, 

 disease breaks out and the rodents die off in thousands. Never- 

 theless, we must bear in mind that mice, rats, and voles form 

 a very large part of the bill of fare of such birds, and thus they 

 must to some extent keep their undue multiplication in abeyance. 

 In connection with the plague of voles and mice in South Scotland 

 in 1892, we learn that " a preponderance of opinion amongst 

 farmers is reported tracing the cause of the present outbreak 

 to the scarcity of owls, kestrels, hawks, weasels, and other 

 vermin " (17, p. 4). 



Moreover Hawks, Falcons, and Harriers undoubtedly take 

 sickly game (although some say this is not so). This must in 

 the end prove beneficial, for their progeny are more likely to 

 prove unhealthy than that of strong stock. 



The Kestrel {Falco tinnunculus, Linn.) is certainly beneficial 

 in its habits, for it feeds almost entirely on mice, voles, young 

 rats, small birds, beetles, and grasshoppers. It is generally 

 acknowledged to be helpful to man, save by gamekeepers, yet 

 it rarely touches either game or poultry ; but according to 

 the Rev. Henry Slater (2) " a rogue kestrel, with a hungry 

 young family of its own to provide for, learns bad habits, and 

 visits the pheasant coops." This is certainly from the general 

 evidence at hand very exceptional, and all, save the majority 

 of gamekeepers, who can discriminate between our Hawks, 

 acknowledge its beneficial nature. With the Sparrow Hawk 

 (Accipiter nisus, Linn.) there seems to be a great difference of 

 opinion. Mr. Fred Smith (3) says it " is too fond of game and 

 poultry to be protected " ; on the other hand, the Rev. Henry 

 Slater (2) says it is " certainly not injurious from a farmer's 

 point of view ... its influence on the farm must be called 

 mildly beneficial." The consensus of opinion is undoubtedly 

 against the Sparrow Hawk. Every one interested in poultry 

 or game is well acquainted with its destructive habits. 



The Peregrine {Falco peregrtnus, Tunstall) may be classed 

 with the Sparrow Hawk as being harmful to game and poultry, 

 but we must bear in mind that it devours rats, mice, and voles. 

 The question is, does the amount of good these two birds do 

 compensate us for the amount of harm ? It is very doubtful 

 if this question is ever likely to be satisfactorily answered. 



