. The Canadian field-naturalist. 1988 Bigg: Status of the Steller Sea Lion 329. Figure 9. Total number of pups and non-pups of Steller Sea Lions seen on rookery groupings in British Columbia, and on Forrester Island, Alaska, during 1913 to 1982, and the cumulative number of non-pups killed in British Columbia. Kills on the Sea Otter Group were assumed to consist of 75% pups. Data from text and Tables 3 and 4. Alternatively, if one ignored the potential effects of harassment and of seasonal timing of censuses, but incorporated a correction for extra pups born and the likely number on North Dang
. The Canadian field-naturalist. 1988 Bigg: Status of the Steller Sea Lion 329. Figure 9. Total number of pups and non-pups of Steller Sea Lions seen on rookery groupings in British Columbia, and on Forrester Island, Alaska, during 1913 to 1982, and the cumulative number of non-pups killed in British Columbia. Kills on the Sea Otter Group were assumed to consist of 75% pups. Data from text and Tables 3 and 4. Alternatively, if one ignored the potential effects of harassment and of seasonal timing of censuses, but incorporated a correction for extra pups born and the likely number on North Danger Rocks, then the population on rookeries numbered at least 11000 in 1913 (Table 3). The range was thus 11000-14 000. By 1938, rookeries of the Sea Otter Group were essentially eliminated through intensive annual kills since 1922 (Figure 9). Countering this decline were increases on the Scott Islands, on Triangle Island and on Sartine Island, although a decrease took place on Beresford Island. Assuming that the 4 000 sea lions seen on the Virgin Rocks in August 1938 originated from the Scott Island, the Scott Island rookeries would have contained about 7 200 animals in 1938. The total number of animals seen in British Columbia during 1938 was similar to that in 1913. However, as the census in 1938 followed reported kills of 7 900 sea lions (2 400 pups) in 1936 to 1938 on the Scott Islands, the rookeries of the Scott Islands must have increased between 1913 and 1936. Thus the total number of animals on rookeries in British Columbia could have increased by several thousand between 1913 and 1936, despite the elimination of most animals on the rookeries of the Sea Otter Group. No kills for management or commercial purposes took place on rookeries between 1940 and 1956, except for one kill on the Scott Islands in 1950. However, the Canadian airforce and navy apparently made substantial kills during the 1940s. By 1956, the total population seen on rookeries in British Columbia had d
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