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MUSEUM BULLETIN NO. 13. 
As it is, the useless slaughter of non -game life that now goes 
on in certain parts of our country is deplorable. The sight of 
hundreds of dead and wounded gannets shot near Perce during 
the summer of 1913 for sport ( ?) and left to lie where they fell 
indicates not only a wanton and unnecessary waste of innocent 
life but a looseness of moral fibre among certain people that is a 
danger to the country at large and should be curbed. The 
attitude of our laws should instil a wholesome regard for the 
rights of lower life and the taking of it uselessly should be dis- 
couraged in every way possible. This does not mean that a 
sentimental quixotic stand should be taken. Whenever the 
end justifies it, no weak sentimentality should be allowed to 
stand in the way of human welfare; but the spirit of our laws 
and people should be such that no creature should be destroyed 
without a good, sufficient, and well considered reason. 
For a proper understanding of the principles to be con- 
sidered before a species is condemned, the following points bear- 
ing upon the subject are advanced. The number of a species 
is dependent upon three main factors: food supply, enemies, 
and birth rate. In order of importance they vary with the 
species and the conditions, permanent and fluctuating, under 
which they live. For the purpose of the present paper, and as 
they relate to salmon vs. birds, the above order of importance 
probably represents normal comparative values. 
The birth rate being controlled within the species itself, 
through the influence of evolution, is flexible and can reasonably 
be supposed to have reached that stage, in any dominant or 
successful species, most profitable to it under existing external 
conditions. It is, therefore, self-correcting and can be placed 
last in the list. The birth rate is, in any thrifty race, always 
much higher than is necessary to merely replace worn out in- 
dividuals. When it is realized that a pair of adults in a stationary 
population, can on an average raise to maturity only an equal 
number of offspring during their life time, it is evident that the 
death rate in all species is enormous. It is also evident that 
the natural birth rate is sufficient for all practical purposes and 
unless the death rate is high during adolescence, the species would, 
in a few generations, increase beyond all reason. 
