After a dramatic population decline, Steller sea lions have begun to recover throughout most of their range. However, Steller sea lions in the Western Aleutians and Commander Islands are continuing to decline. Comparing survival rates between regions with different population trends may provide insights into the factors driving the dynamics, but published data on vital rates have been extremely scarce, especially in regions where the populations are still declining. Fortunately, an unprecedented dataset of marked Steller sea lions at rookeries in the Russian Far East is available, allowing us to determine age and sex specific survival in sea lions up to 22 years old. We focused on survival rates in three areas in the Russian range with differing population trends: the Commander Islands (Medny Island rookery), Eastern Kamchatka (Kozlov Cape rookery) and the Kuril Islands (four rookeries). Survival rates differed between these three regions, though not necessarily as predicted by population trends. Pup survival was higher where the populations were declining (Medny Island) or not recovering (Kozlov Cape) than in all Kuril Island rookeries. The lowest adult (> 3 years old) female survival was found on Medny Island and this may be responsible for the continued population decline there. However, the highest adult survival was found at Kozlov Cape, not in the Kuril Islands where the population is increasing, so we suggest that differences in birth rates might be an important driver of these divergent population trends. High pup survival on the Commander Islands and Kamchatka Coast may be a consequence of less frequent (e.g. biennial) reproduction there, which may permit females that skip birth years to invest more in their offspring, leading to higher pup survival, but this hypothesis awaits measurement of birth rates in these areas.

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Western gray whales Eschrichtius robustus (WGWs) are endangered, and their range overlaps areas where several important commercial fisheries operate in the Russian Far East (RFE). Throughout their range, gray whales commonly become entangled or entrapped in fishing gear. In the western North Pacific, they have been killed in set nets and seen entangled with ropes and float lines. Signs of fishery interactions on 28 of 150 living whales photographed near Sakhalin Island were reported in a published study. We describe characteristics of RFE fisheries that might entangle WGWs, including fishing effort based on daily catch reports from 2010−2014. We make a preliminary qualitative assessment of entanglement risk, taking into account factors including (1) evidence that the gear type has entangled large whales, (2) fishing effort, and (3) geographic and temporal overlap between WGWs and fishing activity. Fishing for salmonids with pelagic gillnets is no longer allowed in the RFE, and as long as the prohibition is being followed such fishing poses no risk to WGWs. In contrast, the coastal salmon set net fishery poses a high entanglement risk off northeastern Sakhalin and Kamchatka where WGWs feed very close to shore, and that situation should be mitigated. Bottom-set gillnet, demersal longline, snurrevad (also called Danish seine), and trap and pot fisheries overlap substantially with WGW distribution, and bycatch in those fisheries should at least be monitored. More rigorous risk assessment would require additional information on WGW distribution and movements.

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