BEAVER HABITS, BEAVER CONTROL, AND BEAVER FARMING. 25 



perfectly prime wild fur is taken in the United States, even in the 

 open season. 



To improve the stock by selective breeding the choicest animals 

 should be reserved for breeders and all inferior ones marketed for 

 fur. For convenience in handling them, the corral traps (see p. 19) 

 should be used. Suitable corrals or feeding yards can be kept in 

 permanent use in order that the beavers may be inclosed at any time 

 while feeding. The more accustomed they become to the presence 

 and voices of people the less nervous and alarmed will they be when 

 it is necessary to capture and handle them. 



MARKING FOR SEX AND AGE. 



The genital organs of beavers are internal, making it difficult to 

 determine the sex. The male has a straight bone an inch to an inch 

 and a half long in the penis, lying between the two large musk glands 

 under the skin just in front of the anus. The female may be recog- 

 nized by the absence of this character and by the two conspicuous 

 teats on each of two mammary glands. The shape of tail and other 

 external characters seem to have no relation to sex. 



Every beaver should be carefully examined and in some conspic- 

 uous way marked for both sex and age. Branding on top of the 

 tail with either a hot iron or chemicals would be permanent and 

 conspicuous. Either recorded numbers or a sex mark and the year 



of birth might be used. 



FEEDING AND CARE. 



Young beavers can be raised on cow's milk and take eagerly to 

 the nursing bottle (PI. VII, Fig. 2). In the early fur-trade days 

 they were occasionally nursed by the Indian women and raised as 

 household pets. They could probably be nursed by such foster 

 mothers as sheep, goats, and possibly dogs. Undiluted cow's milk 

 is apparently too rich for them, so it should be skimmed or separated 

 and boiled, and if it produces diarrhea should be given with lime water. 

 When fresh milk can not be obtained powdered whole milk can be 

 used. While little, beavers must be fed small quantities every four 

 hours, night and day, to keep them quiet. If fed at longer intervals 

 they are sure to overeat, with bad results. They should be encour- 

 aged to eat green vegetation and roots as early as possible. When 

 about 2 months old they may be weaned and will live on green 

 vegetation, leaves, twigs, and bark and roots, with rolled oats and 

 bread as extras. 



In fur farming one of the first considerations is an accessible 

 supply of the proper food. There seems to be no overcrowding or 

 overpopulation in beaver colonies where there is plenty available, 



