680 A CENTURY OF PROGRESS IN THE NATURAL SCIENCES 



The esthetic value of many mammals cannot be denied. Many thousands of 

 tourists visit our National Parks annually. "Wild animals, be they elk, bear, wild 

 sheep, or the teeming populations of smaller species, share with the geysers, 

 waterfalls, and great forests the interest of the people. Summer visitors to our 

 eastern parks delight in the sight of a beaver dam, and drive many miles in the 

 hope of catching a glimpse of a doe with her fawns on some wilderness meadow. 

 Residents of Vilas County, Wisconsin, realizing the recreational value of wildlife 

 to the tourist, posted thousands of acres against hunting. These people realized 

 that deer were a greater asset to them alive and brought a larger reward through 

 summer trade than nonresident hunters could possibly do. In 1946, over 21,000,- 

 000 people visited the 160 acres of the National Park system. They came to see 

 our native mammals as well as the other natural wonders. 



Perhaps more tangible values are to be found in the hunting and trapping of 

 game and fur-bearing species. An increasing number of hunters take to the fields 

 each year. It is fortunate for them that many game species have shown a like 

 increase in numbers. 



The exploitation of our fur resources is woven inextricably with the settlement 

 of the great Mississippi Basin and the West. We have seen that the resultant 

 changes in environment have been responsible for the decline of many species, 

 while others have increased wherever man has partly cleared the forests and 

 farmed the land. Some species are adaptable and can thrive in arable lands, 

 whereas others depend upon wilderness areas. Trapping is big business and 

 provides a partial livelihood to many thousands of Americans. In the early 

 'forties, trapper income was estimated at no less than $100,000,000 annually. 

 While this may appear to be a relatively small figure in so far as products of the 

 land are concerned, the return is very substantial. The money is distributed 

 among the low income group and at a season when a cash crop is most needed. 

 The fur industry is a huge one, employing many people who are directly depend- 

 ent on this great resource. 



Except for the'muskrat and the beaver, we know less about the habits and 

 needs of our fur animals, than we do of the game species. This lack of knowledge 

 may be attributed to several factors. Most important, perhaps, has been the 

 almost universal belief that fur-bearers and vermin are synonymous. This has 

 been particularly true of the weasel, mink, skunk, fox, and other carnivores. The 

 apathy of state game officials has been marked. Fur animals have brought little 

 or no revenue to the state treasuries, hence research on, and legislation for, this 

 valuable resource has not until recently received the attention it merits. 



The annual loss to crops, forage, and forests occasioned by our native mammals 

 is a very real one. Bell (1921) has. placed this monetary loss at $300,000,000. 

 By far the larger share of this loss may be levied against pocket gophers, ground 

 squirrels, field mice, cottontails andjackrabbits, with cotton rats, porcupines, 

 woodchucks, moles, and other species adding to this destruction. It is a well known 

 fact that wild mammals may transmit virulent diseases to man and his livestock. 

 The study of the diseases of wild mammals is still in its infancy; man and his 

 domestic animals frequently contract these diseases. AVhen outbreaks of rabies, 

 tick fever, or endemic typhus break out among feral species, it has been found 

 necessary, often at considerable expense, to conduct extensive campaigns against 

 these animals. Such wholesale slaughter is regrettable but inevitable when con- 



