Chapter III — Species of Special Concern 
the recommended expansion. It noted, however, that 
a member of the Hawaiian Islands National Wildlife 
Refuge staff would be invited to attend future Recov- 
ery Team meetings. It also noted that expertise in the 
field of physical oceanography would be made avail- 
able on a consulting basis at the team’s request. As 
indicated above, in lieu of adding another behavior 
expert to the team, the Service planned to convene a 
separate meeting in 1992 to review matters related to 
mobbing. The meeting was not held during 1992. 
At the end of 1992 a Recovery Team meeting 
scheduled for December 1992 was canceled by the 
Service due to limited funding. To ensure that a 
meeting was convened prior to the 1993 field season, 
the Commission therefore offered to provide funds to 
cover travel expenses of non-Service participants. 
With this assistance, the Service rescheduled the 
Recovery Team meeting for 4-5 January 1993. 
Steller Sea Lion 
(Eumetopias jubatus) 
Steller or northern sea lions inhabit coastal areas 
along the rim of the North Pacific Ocean from the 
Channel Islands in southern California through the 
Gulf of Alaska and Aleutian Islands to northern 
Hokkaido, Japan. In the United States, Steller sea 
lions are most abundant in the Aleutian Islands and 
Gulf of Alaska. 
Available information indicates that the number of 
Steller sea lions has declined substantially throughout 
most of their range. Censuses of major rookeries and 
haulout areas in the Gulf of Alaska and Aleutian 
Islands in the United States and in the Kuril Islands in 
Russia indicate declines in some areas of more than 
90 percent over the past three decades. These de- 
clines have occurred principally during the past ten 
years. Between 1985 and 1989, for example, the 
number of sea lions counted in the eastern Aleutian 
Islands declined by more than 60 percent. Numbers 
have remained stable in southeastern Alaska and 
southward, except for California, where they have 
declined. A summary of available data concerning 
past and present Steller sea lion numbers in the United 
States, Canada, and Russia is provided in Table 4. 
35 
The cause or causes of the decline are uncertain. 
Possibilities include over-exploitation of prey species, 
commercial hunting prior to 1972, subsistence hunting 
by Alaska Natives, incidental take in commercial 
fisheries, deliberate shooting and harassment at or 
near rookeries and haulout sites, and disturbance by 
boats and aircraft. Natural factors, such as changes in 
environmental conditions, predation by sharks and 
killer whales, and disease, also are possibilities. 
In the central Gulf of Alaska, where the only long- 
term studies have been done, Steller sea lions seem to 
be growing more slowly and reaching sexual maturity 
later than in the past, suggesting that decreased food 
availability may be at least one of the causes of the 
decline. Decreased food availability may be due to 
human exploitation of important prey species, such as 
walleye pollock (Theragra chalcogramma), environ- 
mental change, or both. 
Protective Actions 
As noted in previous annual reports, the National 
Marine Fisheries Service designated the Steller sea 
lion as threatened under the Endangered Species Act 
in November 1990. In addition, the Service estab- 
lished a Steller Sea Lion Recovery Team to assess and 
provide advice on measures necessary to stop and 
reverse the population’s decline. 
The Recovery Team subsequently prepared a Tech- 
nical Draft Steller Sea Lion Recovery Plan and, in 
March 1991, the Service asked the Commission for its 
comments on the document. The plan recommended 
“immediate actions...to reduce human-caused mortali- 
ty to the lowest level practicable, protection of impor- 
tant habitats through buffer zones and other means, 
and enhancement of population productivity by 
ensuring that there is an ample food supply available.” 
To implement these recommendations, the draft plan 
recommended several research and conservation 
actions, including (1) identifying habitat requirements 
and protecting areas of special biological significance; 
(2) identifying management stocks; (3) monitoring the 
status and trends of the species; (4) monitoring the 
health, condition, and vital parameters of the species; 
(5) assessing and minimizing the causes of mortality; 
(6) investigating feeding ecology and factors affecting 
