THE EXTERMINATION OF WILD LIFE 23 
the chances of serious reduction and ultimate extermina- 
tion are enormously increased. The second requisite in the 
conservation of a species of game animal is a realization of 
the effect that inevitably follows the killing of the most 
virile males. The sportsman’s aim is usually to secure the 
finest specimen, which usually implies the largest male; in 
the case of deer this means the best head. If this quest is 
carried out to excess it may involve the destruction of the 
most virile animals to an extent that would affect the gen- 
eral virility of the local stock of game with the obvious re- 
sults. The stock would undergo degeneration, and the de- 
structive effects of natural factors would be correspondingly 
enhanced. The remedy for this state of affairs is regula- 
tion as regards the number of males that may be killed, and 
the maintenance of a virile nucleus by means of protected 
refuges. The latter remedy will be considered more fully 
in a later chapter. 
Apart from inadequate protection, which is an avoidable 
factor in ultimate extermination, great reduction in numbers 
has been brought about in the case of our wild fowl, such as 
ducks and geese, by the extension of agriculture in various 
parts of the country, but particularly in the Prairie Prov- 
inces. The drainage of swamps and natural breeding-places 
has been an important factor in the reduction of our supply 
of wild fowl. And these birds have been gradually pushed 
further afield from their former breeding-places. The rem- 
edy for this state of affairs, so far as a remedy can be ap- 
plied, is the reservation of areas unsuitable for profitable 
agriculture as refuges and breeding-places to secure as 
abundant a local supply of birds as possible. 
Inadequate protection of wild fowl during the spring has 
been one of the chief causes of an avoidable character of the 
great reduction in the numbers of ducks, geese, and shore- 
birds. Spring shooting, had it been permitted to continue 
—by international action, of which I shall speak later, it 
