WILDLIFE CONSERVATION 791 



One last instance, the grizzly bear, noblest of American flesh-eaters, 

 was formerly present widely over the western United States, as well 

 as in Alaska and the extreme northern parts of North America, and 

 in northern Mexico. Merriam's studies show what a wealth of forms 

 were represented. Unlike the black bear, which is among the shyest 

 of animals, the grizzly was courageous and much more inclined than 

 the black to dispute man 's encroachment on his hereditary range. In 

 this way poor old Ursus liorrihilis (the name itself has a majestic 

 sound) proved to be not so well adapted to modern conditions as the 

 black bear. Now all the grizzlies are gone from the United States, ex- 

 cept in a few scattered localities in the West, where they maintain a 

 precarious existence under special protection or other unusual condi- 

 tions. Fortunately, there are a good many of these splendid animals 

 still remaining in Canada and Alaska. 



Detailed consideration of our valuable wildlife shows a discourag- 

 ing decrease in almost every instance during the three hundred years 

 or more of our occupation of North America. However, there are 

 a few cases in which the natural range of wild animals has been 

 increased as a result of man's activities. Everyone is familiar with 

 the English sparrow and the starling in America, the muskrat in 

 England and on the continent of Europe, the rabbit in Australia, the 

 house mouse and the Norway rat generally wherever civilized man is 

 found. In most cases, unfortunately, these increases result from 

 man's unintelligent meddling with natural conditions, and result in 

 much damage to his interests. The Norway rat is undoubtedly the 

 most dangerous and costly mammalian enemy of mankind in the 

 whole world. 



In a few places, favorable ecological conditions combined with pro- 

 tection by man or a reduction in the number of natural enemies have 

 resulted in an abnormal increase in numbers of game species ordi- 

 narily considered valuable, and sometimes developed detrimental sur- 

 pluses. Protection of deer on certain royal forests in England and on 

 the continent of Europe has sometimes seriously interfered with the 

 normal growth of the trees and other vegetation. On the Kaibab 

 Plateau north of 'the Crrand Canyon of the Colorado River, in the state 

 of Arizona, the deer, numbering normally perhaps 3,000 or 4,000 

 individuals, increased to a number estimated at 30,000 to 100,000 ani- 

 mals. The future of the deer's own food supply, and indeed of the 

 Kaibab Forest, was threatened. There is no more reason for op- 



