322 ECONOMIC MAMMALOGY 



The caribou of northern United States, British America and Alaska 

 (Rangifer) is closely related to the reindeer, and has furnished food 

 and raiment not only to the natives of the North, but to numerous 

 white prospectors, trappers, explorers and settlers within the caribou 

 country. 72 One herd was estimated at from 100,000 to 200,000 caribou, 

 and during migration caribou are said to have passed Fort Rae for 14 

 days in an unbroken line, in such a mass that "daylight could not be 

 seen" through the column. 73 Seton estimated one herd of barren- 

 ground caribou at 25,ooo,ooo 74 The caribou has been practically ex- 

 terminated in the Arctic coastal portion of Alaska, largely for the 

 skins, and is now scarce on the Mackenzie delta. 75 As better trans- 

 portation facilities render the movement of skins easier and less ex- 

 pensive, greater inroads will be made upon the herds of the interior 

 unless ample protection is provided by the government. That is just 

 what happened to the American bison. 



The caribou eats more or less grass in the summer, but in winter 

 its food is chiefly "reindeer moss," where it may be had, otherwise 

 browse of willows and the like. In Labrador the abundance of caribou 

 is somewhat regulated by the abundance of mice. When the mice are 

 abundant they furnish plenty of easily obtained food for the wolves, 

 which then leave the caribou alone, returning to a caribou diet when 

 mice became too scare to satisfy them, 76 a striking example of the 

 interactions of organisms. 



FAMILY GIRAFFIDAE GIRAFFES AND OKAPIS 



The giraffe, native of Africa, "has no economic value, nor is it 

 very intelligent." 1 These great animals are picturesque in their native 

 haunts, exceedingly interesting in parks and menageries, and their skins 

 find a ready market. They have been slaughtered in large numbers, 

 "almost solely for the hide, which is worth from 3 to 5 in the case 

 of full-grown beasts; so perishes the giraffe from South Africa." 2 

 They are browsers, feeding on the buds, leaves and twigs of trees, 



72 Hadwen and Palmer, U. S. Dept. Agric. Bull. No. 1089, p. 3, 1922. 



73 Preble, A biological investigation of the Athabasca-Mackenzie region, N. Amer. 

 Fauna, No. 27, p. 141, 1908. 



74 Seton, The Arctic prairies, p. 259, 1917 (cited by Adams) ; Lives of game 

 animals, in, Part i, pp. 97-135, 1929. Adams, The economic and social importance 

 of animals in forestry, with special reference to wild life, Roosevelt Wild Life Bull., 

 in, 576, 1926. 



75 Hewitt, The conservation of the wild life of Canada, pp. 59-66, 1921. 

 78 Allen, Journ. Mammalogy, in, 56-57, 1922, reviewing Cabot's Labrador. 

 ^ennison, Natural history: animals, p. 226, 1927. 



2 Nature Lovers Library, v, 239, 1917. 



