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Survival rates of endangered western stock Steller sea lions Eumetopias jubatus east of Samalga Pass (~170°W) have rebounded to nearly the same levels estimated for the 1970s prior to their decline in abundance. We estimated survival of sea lions hot-branded as pups (N = 1449) in 2000−2005 using Cormack-Jolly-Seber mark-recapture models and sighting data collected through 2011. Survivorship to Age 7 yr was greater for females (range: 0.352−0.386) than males (0.228−0.275), but was similar for each sex across the study area. Survival was lowest in the first year and increased through Age 4+ yr for both sexes in the eastern Gulf of Alaska (144−150°W). However, to the west, first-year survivorship was greater or equal to that of Year 2, and the difference was generally greater for males than females. Regional differences in the pattern of early survival could reflect spatial variability in early life history (e.g. duration of maternal care, growth rate) or habitat characteristics (e.g. prey availability, rates of predation). Population models indicate that natality of the increasing population east of Samalga Pass in 2000−2012 may not be significantly different from rates estimated for the 1970s prior to the decline in overall western abundance. Given current information, western Steller sea lions may satisfy the stock-wide demographic down-listing (to threatened status) criterion by 2015. However, due to continued abundance declines west of Samalga Pass, where no survival data are currently available, it is less certain that the western stock's regional down-listing criteria will be achieved.

Between 1991 and 1993, Alaska harbor porpoise (Phocoena phocoena) abundance was investigated during aerial surveys throughout much of the coastal and offshore waters from Bristol Bay in the eastern Bering Sea to Dixon Entrance in Southeast Alaska. Line‐transect methodology was used, and only those observations made during optimal conditions were analyzed. Survey data indicated densities of 4.48 groups/100 km2, or approximately 3,531 harbor porpoises (95% C. I. 2,206‐5,651) in Bristol Bay and 0.54 groups/100 km2, or 136 harbor porpoises (95% C. I. 11‐1,645) for Cook Inlet. Efforts off Kodiak Island resulted in densities of 1.85 groups/100 km2, or an abundance estimate of 740 (95% C. I. 259‐2,115). Surveys off the south side of the Alaska Peninsula found densities of 2.03 groups/100 km2 and an abundance estimate of 551 (95% C. I. 423‐719). Surveys of offshore waters from Prince William Sound to Dixon Entrance yielded densities of 4.02 groups/100 km2 and an abundance estimate of 3,982 (95% C. I. 2,567‐6,177). Combining all years and areas yielded an uncorrected density estimate of 3.82 porpoises per 100 km2, resulting in an abundance estimate of 8,940 porpoises (CV = 13.8%) with a 95% confidence interval of 6,746‐11,848. Using correction factors from other studies to adjust for animals missed by observers, the total number of Alaska harbor porpoises is probably three times this number.