Chapter III — Species of Special Concern 



from 1990 to 1994 for various sectors of the Bering 

 Sea groundfish fishery, the only fishery reported to 

 incidentally take walruses, indicated an annual inci- 

 dental-take rate of about 16 animals. The Service 

 concluded this was an insignificant level that met the 

 Marine Mammal Protection Act goal of approaching 

 a zero level of mortality and serious injury. 



Considering total catch landings of walruses in the 

 United States and Russia, plus an estimate of animals 

 that were struck and lost, the Service estimated that 

 the average annual level of human-related mortality 

 and serious injury for the past five years was 5,894 

 animals. As this was below the estimated potential 

 biological removal rate, the Service concluded that the 

 Pacific walrus stock was not a strategic stock. 



Sea Otter 

 (Enhydra lutris) 



The sea otter is the smallest marine mammal in the 

 world with the exception of the marine otter (Lutra 

 felina). It is the only member of the genus Enhydra, 

 and comprises three identified subspecies: E.l. lutris, 

 E.l. nereis, and E.l. kenyoni. 



Sea otters were historically found in nearshore 

 waters of the North Pacific Ocean, from Hokkaido in 

 northernmost Japan through the Kuril Islands, Kam- 

 chatka Peninsula, the Commander Islands, the Aleu- 

 tians, peninsular and south coastal Alaska, and south- 

 ward down the west coast of North America to Baja 

 California. Prior to the mid- 18th century, the world- 

 wide population of sea otters was estimated at 150,000 

 to 300,000 animals. 



The Russian discovery of Alaska in 1741 led to 

 intense commercial exploitation of sea otters that 

 continued without regulation for 150 years. By the 

 early 1900s, the total sea otter population was reduced 

 to as few as 1,000 to 2,000 animals existing in 13 

 small and widely scattered remnant groups. 



Commercial exploitation of the species ended with 

 the North Pacific Fur Seal Convention of 1911, an 

 agreement between the United States, Russia, Great 

 Britain, and Japan. With this protection, sea otters 



have recolonized or have been reintroduced into a 

 substantial part of their historic range in Russia, the 

 Aleutian Islands, south coastal Alaska, British Co- 

 lumbia, Washington, and California. 



In the past 20 years, however, new threats have 

 developed. They include possible oil spills from 

 tanker accidents and well blow-outs, entanglement in 

 fishing gear, and marine pollution. 



Efforts by the Marine Mammal Commission and 

 others to ensure the continued protection of sea otters 

 and their habitat have been discussed in previous 

 annual reports. A summary of these actions and a 

 discussion of efforts undertaken in 1995 follows. 



The Central California Population 



The sea otter population in California was nearly 

 eradicated by commercial hunting. By the time 

 protection was afforded in 1911, the total sea otter 

 population in California may have numbered fewer 

 than 50 animals found within a few miles of nearshore 

 habitat along the rocky Point Sur coast. Under the 

 Fur Seal Convention and additional protective mea- 

 sures later implemented by the State of California, the 

 population increased slowly. By the mid-1970s, 

 approximately 1,800 sea otters inhabited nearshore 

 areas along 160 miles of the central California coast. 

 More recent population counts are shown in Table 7; 

 the 1995 counts continued an upward trend that began 

 in the 1980s. 



Because of its small size and limited distribution, 

 and the growing risk of oil spills as a result of in- 

 creasing tanker traffic in the area, the population was 

 designated as threatened under the Endangered Species 

 Act in January 1977. At that time, it was recognized 

 that perhaps the best way to minimize the risk from 

 oil spills would be to encourage further expansion of 

 the population's range. However, such range expan- 

 sion could impact commercial and recreational abalone 

 and other shellfish fisheries that had developed in the 

 absence of sea otters. In response to this realization, 

 the Fish and Wildlife Service, acting on a December 



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