. . . Pacific Marine Mammals 



104 



Figure 23-1.— Actual count of 

 bowhead whales, 1978-88. 



6,000 



o 

 o 



o 



4,000 



i 



O 3,000 



2,000 



1975 



1980 



1985 



1990 



Figure 23-2— Estimated 

 population of gray whales, 

 1965-90. 



Northern Sea Lion 



The northern or Steller sea lion, classified 

 as threatened under the ESA, ranges 

 coastal waters of the North Pacific Ocean 

 from California to Japan. The species has 

 declined sharply throughout its range in 

 just the last 20 years, and is now well below 

 its optimum level. The number of adults 

 and juveniles in U.S. waters crashed from 

 154,000 in 1960 to 42,000 in 1990. Most 

 of this 73% decline occurred in Alaska 

 waters, where sea lion counts at three 

 study sites were 105,289 in 1959; 89,364 



in 1976; 55,824 in 1985; and 23,000 in 

 1990 (Fig. 23-3). The decline in Alaska is 

 believed to be due to a combination of 

 incidental kills in fisheries, illegal shooting, 

 changes in the numbers and/or quality of 

 prey, and possibly other unidentified fac- 

 tors. (The Steller sea lion population off 

 Washington and Oregon is low but stable 

 at about 3,000, but in California they have 

 slowly declined since the 1950's to about 

 2,000.) 



