14 MUSEUM BULLETIN NO. 28. 



most raptoral species prefer fur to feathers when it can be obtained. 

 This is probably more a matter of greater opportunity than taste, but 

 seems to be a fact except in a few exceptional and fortunately rare 

 species. 



As these invasions seem to be governed by the rabbit situation more 

 than any other factor there seems to be no means' of controlling them. 

 All that can be recommended is to kill as many of the offenders as 

 possible. Probably the crisis of the present cycle is over now. The 

 northern raptores have had two rabbitless seasons and have exhausted 

 the grouse. Following the laws of cause and effect their numbers must 

 also be considerably reduced through lack of food and the forms that 

 they preyed upon will have an opportunity for recovering. 



The course here recommended of encouraging and protecting the 

 useful species of hawks and destroying the harmful ones necessitates 

 careful discrimination between the two classes. Unfortunately, the 

 knowledge necessary to distinguish the different species is not widespread 

 and to most people a hawk is a hawk and to be killed at every opportunity. 

 With so much at stake a farmer or sportsman is no more justified in 

 advancing ignorance as an excuse than he is in proclaiming his inability 

 to distinguish between crops and weeds or to know the various insect 

 pests that he has to fight, or the game that the law allows him to shoot. 

 In fact discrimination is a part of his business as farmer or sportsman and 

 as such should be studied. 



Until a better knowledge of the usefulness and harmfulness of our 

 birds of prey is more widely distributed the following rule for action can 

 be given for the southern prairie provinces protect and encourage the 

 larger summer hawks, except those actually caught in the act of poultry 

 killing, and destroy the winter ones when opportunity offers. In this 

 way a few harmful hawks may escape and a few innocent ones suffer, 

 but the results on the whole will be a great step in advance of the present 

 practice of indiscriminately killing friend as well as foe. 



