hour before the beaver came out. At first I was often puz- 

 zled to distinguish, in the twilight, rats from small beaver; 

 but after a few evenings spent on the platform I learned that 

 the rats were of a lighter brown than the beaver, and that 

 they swam with their backs slightly out of the water, while 

 a beaver only showed his head above water. Later I learned 

 to distinguish the rats even in the dark by their quick move- 

 ments and by the nervous puttering noises they made in feed- 

 ing on bark or plants as well as in diving. 



I estimate that there are bout forty beaver houses in and 

 near the park, and allowing an average of eight beaver to a 

 house, this would give three hundred twenty animals. Per- 

 haps eighty would be a reasonable number to allow for those 

 living in bank burrows and not in houses, which would bring 

 the total beaver population up to four hundred. 



Value and Increase. 



Eight dollars would not be too high an average value for 

 a beaver skin, making the money value of the beaver in Itasca 

 $3,200. As near as I can tell from observations on a number 

 of beaver houses, the usual number of beaver produced in a 

 season is four, and there is only one litter during the year. 

 It would seem that the annual increase of beaver is probably 

 somewhere between twenty-five and forty per cent. This 

 should make it perfectly safe, in a region where beaver are 

 raised for the fur, to allow a catch of fifteen to twenty per 

 cent annually. 



Re-Stocking Forests With Beaver. 



There are large regions in Canada, in Michigan, Wisconsin 

 and Minnesota, which furnish excellent beaver range and 

 which should be re-stocked. The experiment which the state 

 of Minnesota has made in Itasca park shows that it is entirely 

 practicable to re-stock a region with beaver, provided the nat- 

 ural conditions are favorable. The animals are not generally 

 subject to any disease, and by their aquatic habits protect 

 themselves against their natural enemies; but they must be 

 protected against poachers. 



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