90 COMMISSION OF CONSERVATION 



It is said that the best salt marshes will furnish 50 rats a year per 

 acre. They may be fenced with l^^-inch mesh wire, 5 feet w4de, by 

 burying it a foot on dry land and deeper near water area. Not more 

 than 50 rat houses, or pairs, should be kept on an acre. It is necessary 

 to have an area of water which does not freeze to the bottom. This, 

 in many cases, could be secured by dredging and the mud thrown up 

 would be used by the rats for making homes. Wild rice, water lilies, 

 cat-tails, and various roots, are their natural food. Carrots, beets, 

 turnips, apples, pumpkins and other cheap vegetables and fruits may 

 be grown in nearby fields for summer food, or stored in pits for winter. 

 A small quantity of meat may also be fed. 



The muskrat probably has only two litters a year in the colder 

 parts of Canada, but farther south, three litters are bom, and the first 

 litters bear young in the autumn. The first are born about the middle 

 of May and each litter numbers from four to nine, although as many as 

 twelve have been reported. 



BEAVER 



(Castor Canadensis) 



The beaver formerly existed over nearly all the continent of North 

 America. It was also found in Europe and the greater part of Asia and 

 Northern Africa, but, in most of these, became extinct centuries ago. 

 There are only a few colonies in Europe at the present time and these 

 are preserved carefully by government authorities. It is rapidly becom- 

 ing extinct in America. The homes of the greatest numbers, at the pre- 

 sent time, are in the country between the Great lakes and the St. 

 Lawrence river northward to Hudson bay, and in noi-them British 

 Columbia. 



No animal did more than the beaver to effect the colonization of 

 America. It lured men into the most remote wildernesses, furnished 

 him food and clothing, and was one of the chief articles of commerce 

 with Europe. So universal an article of trade did it become that, in 

 northern Canada, beaver skin became the unit of currency. 



Brass estimates the world's production as follows : America, 80,000 

 skins; Asia, 1,000; Europe, a few. Besides the skins, the castorum, 

 or dry beaver castor, is traded in, bringing from $12 to $15 a pound 

 at the present time. 



Because of its interesting habits, every schoolboy is well 



Uses of . T 



the Beaver acquainted with most phases of the life of the beaver. Its 



rlesh, skins and castors are valuable, the latter being used 



as a base in perfume manufacture. The flesh is excellent and the 



tail is considered a delicacy. The skin was formerly used in the manu- 



