220 



NORTH AMERICAN FAUNA 



[No, 55 



291}). At their lowest ebb a few remained in the larger rivers, how- 

 ever, and during the past quarter century under the awakened interest 

 in wildlife and the most rigid legal protection that could be given 

 them in an area of extensive wilderness they have come back to some 

 of their old haunts and increased locally until they now may be 

 found in many of the streams and lakes of the State. In fact, they 

 are apparently more common now in the Grand Ronde and Walla 

 Walla Valleys than they were a hundred years ago when these 

 valleys were occupied by settlements of Indians who depended 

 largely on the native animals for food and clothing. 



In recent years beavers have been reported as more or less common 

 locally in Clatsop, Columbia, Tillamook, Benito, Lane, Hood River, 

 and Jackson Counties west of the Cascades, and in Wasco, Sherman, 

 Crook, Wheeler, Gilliam, Umatilla, Wallowa, Union, Baker, Grant, 

 and Malheur Counties east of the range. * 



General habits. Beavers are so highly specialized for life in the 

 water and so slow and clumsy on land as to be closely restricted to 

 streams, lakes, and ponds, the shores of which they rarely leave for 

 more than a short distance in search of food. In the water they are 

 rapid and powerful swimmers and great divers, often remaining 

 under water for several minutes at a time and swimming long dis- 

 tances without appearing at the surface, digging, cutting roots and 

 sticks, and gathering much of their food under water. The very 

 large and fully webbed hind feet are powerful swimming members, 

 while the broad, flat muscular tail is used in steering and diving, for 

 a prop in standing up, or for striking a signal blow on the water or 

 ground. Beavers are intelligent, skillful, and industrious workers, 

 building extensive dams across streams to hold back sufficient depth 

 of water in ponds to protect their houses and winter stores of food, 

 and building large, strong, and comfortable houses in which to live 

 and raise their young. They cut trees and bushes for food and build- 

 ing material and show great skill and industry in getting material 

 and carrying on their building and food-storing operations. When 

 much hunted and trapped for their valuable fur they become very 

 shy and difficult to catch, but when protected for a time become gentle 

 and unsuspicious. They are easily tamed and make interesting pets 

 if properly handled. Often in their native haunts they can be baited 

 with favorite food plants, such as the aspen and cottonwood branches, 

 thrown in the water or laid on the shore every day until they come 

 regularly for the food. In this way they may be kept in localities 

 where desired, and even induced to come out before dark to feed in 

 places where they may be observed at close range. While largety 

 nocturnal in habits, and strictly so when persecuted by much trap- 

 ping, they usually come out and begin work before dark and continue 

 their activities until after daylight if unmolested. 



Breeding habits. Female beavers have normally 4 pectoral mam- 

 mae on 2 large breast mammary glands, and 4 seems to be the 

 usual number of young in a litter. In yearling females breeding 

 for the first time there are often only 2 young, while in older 

 females the number is sometimes 6 and there are a few records 

 of 8 embryos in old females. The young are nursed by the mother 

 in the houses or bank dens until old enough to dive through the 



