198 



NORTH AMERICAN FAUNA 68 



The rate of increase of these three colonies is related inversely 

 to their distances from the large western Andreanof population : 







Annual rate of increase 





Distance from 







Colony 



large population 



1959-62 



1962-65 





( miles ) 



(percent) 



(percent) 



Seguam 



130 



10 



10 



Amlia 



100 



12 



13 



Atka 



60 



30 



85 



Possibly the annual rate of increase of the Seguam colony 

 represents the rate of increase that may be attributed to local 

 reproduction in an uncrowded population. 



Summary 



1. In 1741 when unregulated exploitation of the sea otter be- 

 gan, the species ranged from central Lower California, Mexico, 

 north along the coast of the North Pacific Ocean, through the 

 Aleutian and Kuril Islands to the northern islands of Japan. 



2. The northern limit of the sea otters' range overlaps but 

 slightly the usual southern limit of winter drift or pack ice in the 

 Bering Sea. The farthest north colony in Alaska is in Prince 

 William Sound (60°30' N. lat.) where the sea does not freeze. 



3. The total population of sea otters in 1740 was probably 

 between 100,000 and 150,000 animals. 



4. The number of sea otters taken during 170 years of un- 

 regulated exploitation is not recorded but probably did not much 

 exceed one-half million animals. 



5. The total world population in 1911, when exploitation of 

 the sea otter was halted, probably numbered between 1,000 and 

 2,000 animals. 



6. Small sea otter populations apparently remained in 1911 

 at the following 11 areas: Kuril Islands, Kamchatka Peninsula, 

 Commander Islands, Rat Islands, Andreanof Islands, the Unimak, 

 Sanak Islands-Sandman Reefs area, Shumagin Islands, Kodiak 

 Island and Prince William Sound area, in the Queen Charlotte 

 Islands, British Columbia, on the coast of California near Mon- 

 terey, and in the San Benito Islands, Baja California. 



7. The first modern data on the recovery of sea otter popu- 

 lations were obtained in the Aleutian Islands in the mid-1930's 

 and considerable miscellaneous data were subsequently gathered 

 during the 1940's. Detailed field studies of population and distri- 

 bution were begun by the Fish and Wildlife Service in 1954 and 

 continued through 1965. 



