424 EXTINCT AND VANISHING MAMMALS 



Barabash-Nikiforov, who analyzed many droppings and found 

 that in the Kurile Islands remains of sea-urchins constituted 

 about 59 percent of their content, mollusks 23 percent, crabs 

 about 10 percent, fish about 7 percent, and seaweeds a trace. 

 Further details may be found in a paper by Murie (1940). 

 Aside from man, their chief natural enemy is probably the 

 killer whale, small groups of which haunt these seas and 

 especially those about the more northern fur-seal rookeries. 



While this recovery in numbers is encouraging, it must be 

 evident that the building up of a considerable population will 

 be slow. At the present time the Kurile herd must number 

 nearly 700 or more, while information supplied by the Alaska 

 Commercial Co. of San Francisco states that reports of sub- 

 stantial numbers have come to them from Atchitka and Rat 

 Islands of the Aleutians; other estimates of the sea-otter popu- 

 lation in the western part of this chain place the numbers at 

 several hundreds. From southeastern Alaska there have been 

 as yet no reports. That the numbers in the Kurile Islands are 

 now sufficient to warrant the taking of a certain proportion for 

 commercial purposes is indicated by the fact that according to 

 the Fur Trade Review Weekly of May 4, 1939, 50 sea-otter 

 skins were sold at recent London fur sales. "At about the 

 same time The New York Auction Company offered 22 and 

 the Fouke Fur Company of St. Louis, 10 pelts of this animal." 

 Investigation has shown that all these were legally killed in the 

 Kurile Islands by the Japanese Government, and "were certi- 

 fied in accordance with the Act of August 24, 1912" (Journ. 

 Mammalogy, vol. 20, p. 407, 1939). If the sea otter continues 

 to increase it may eventually with proper management be 

 made a productive source of profit once more. 



Order PINNIPEDIA: Seals, Sea-lions, Walruses 



The sea-lions, seals, and walruses are related to the carni- 

 vores, differing from the latter group in the finlike structure of 

 the feet. There are three families : 



(1) Otariidae, the eared seals, sea-lions, and fur seals, or sea- 

 bears. Representatives of this family occur on the temperate, 

 subarctic, and austral shores of the Pacific, southern Atlantic, 

 Indian, and northern Antarctic Oceans. Six species of the 

 southern fur seal and three forms of the northern genus are dis- 

 cussed here. 



