BEAVER 



Measurements. — No very great difference in size between 

 sexes. Total length, 43 inches; tail vertebrae, 16 inches long 

 by 4.5 inches broad; hind foot, 7 inches; weight, 30 pounds to 

 maximum of 68 pounds. 



Geographical Distribution. — Most of North America from 

 Alaska and Labrador to the Rio Grande. 



Food. — Bark, twigs, even wood, of deciduous trees, espe- 

 cially aspen, cottonwoods and willows; also other vegetable 

 matter such as roots of aquatic plants, grass, etc. 



Enemies. — Bear, Wolf, Fisher, Otter, Lynx and Wolverine. 



Species and Subspecies of the Genus Castor 



Canadian Beaver.^ — Castor canadensis canadensis Kuhl. 



As described above. Found in northern North America 

 from nearly 70° north in Yukon and 58° in Labrador, south 



Fig. 66. Forefoot of Beaver 



to about 35° in eastern and central states, and 45° in the 

 Rocky Mountain section. 



Vancouver Island Beaver. — Castor canadensis leucodonta Gray. 

 Resembling typical canadensis but larger, and general color- 

 ation of pelage paler, Upperparts cinnamon-buff. Total 

 length, 46 inches; tail vertebrae, 18 inches; hind foot, 8 

 inches. Found on Vancouver Island, British Columbia. 



Pacific Beaver. — Castor canadensis pacificus Rhoads. 



Largest of the Beavers; slightly paler than leucodonta. Up- 

 perparts dark, glossy, reddish chestnut; underparts seal- 

 brown. Total length, 46 inches; tail vertebrce, 14 inches; 

 hind foot, 7.4 inches; scaly portion of tail 11.8 by 5 inches. 

 Found on the Pacific slope from southern Oregon to Alaska. 



Admiralty Beaver. — Castor canadensis phceus Heller. 



Darker than leucodonta to which it is most closely related. 

 Upperparts dark seal-brown, the long hairs almost black, 



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