ACCEPTING THE UNIVERSE 



owls would soon starve; if she put them all in wood- 

 chucks, the pastures and meadows would soon fail 

 the herds. And this reminds me how man often dis- 

 turbs the balance of nature; the clearing-up and the 

 cultivation of the land have held in check the natu- 

 ral enemies of the woodchucks — foxes and owls — 

 at the same time that they have greatly increased 

 the woodchuck's sources of food-supply, so that in 

 some sections these rodents have become a real pest 

 to the farmer. The same changed conditions appre- 

 ciably favor the meadow mice, and they, too, seem 

 to be on the increase. But this increase again may 

 stimulate the increase of the mice-hunting hawks, 

 and thus the balance be maintained. Herein lies the 

 danger of introducing new forms of wild life in a 

 country — their natural enemies are not always on 

 hand to check them. The mongoose has overrun 

 Jamaica and has not yet found an adequate natural 

 enemy. Introduced into this country, it would be 

 an incalculable calamity, though in time it would 

 doubtless meet with a natural check. Our weasels, 

 related to the mongoose, are prolific, and seem to 

 have few natural enemies, and yet they do not 

 unduly increase; it seems as if some unknown hand 

 must stay them. They prey upon all the smaller 

 rodents and find them easy victims, yet these ro- 

 dents are vastly more numerous than the blood- 

 suckers. I often see marks upon the snow where the 

 muskrat and the rabbit have fallen before them, and 



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