Chum salmon (Oncorhynchus keta) are an important natural resource in western Alaska for subsistence, commercial and cultural reasons. Declines in chum salmon returns in some western Alaska drainages over the last couple of decades have prompted regulatory changes and bolstered research on this species in this region. Since 2002, juvenile chum salmon have been collected as part of the annual U.S. Bering-Aleutian Salmon International Survey (BASIS) during the late summer/fall season in the eastern Bering Sea. From the 2003-2007 collections, nearly 5,000 juvenile chum salmon samples were genetically analyzed. With the available microsatellite baseline, regional stock estimates were produced from mixed-stock analyses. The proportions of juvenile chum salmon from four western Alaska regionsNorton Sound, lower Yukon (summer-run), upper Yukon (fall-run), and Kuskokwim/northeastern Bristol Baywere remarkably similar across years during early marine residence, especially given the latitudinal shifts from year-to-year in the distribution across the eastern Bering Sea shelf of this highly migratory species. Most of the juvenile chum salmon were from the Yukon River, which has two life-history types, an earlier and typically more abundant summer run, and a later fall run. The Kuskokwim/northeastern Bristol Bay contribution within the study area (lat. 58-63N) was negligible, indicating that these stocks do not migrate northward during their first summer. The Norton Sound group contribution varied annually, but in general, increased with latitude. These results support a migration model whereby western Alaska juvenile chum salmon, after leaving freshwater, head primarily west and south across the eastern Bering Sea shelf. A relative abundance index was developed from the proportions of the two life-history types in the Yukon River of juvenile chum salmon in the survey area. In all five years of collections, the summer-run contribution was higher than the fall-run contribution in the juvenile chum salmon samples. The proportions of the two life-history types in the juvenile chum salmon collected at sea were compared with those in the Yukon River adult returns. A correlation was found between the juveniles and subsequent adult returns. This suggests that it is during the period of freshwater and early marine residence that the cohort strength of Yukon River summer- and fall-run chum salmon is determined.

Polar Ecosystems Program research projects focus primarily on abundance, trends, distribution, health and condition, and foraging behavior of phocids (harbor, bearded, ringed, spotted, and ribbon seals) in Alaska. This database represents data associated with live captures and specimen collection of all these species across a variety of research projects. Data include information such as capture date, location, time, and handling time, as well as information about each animal (e.g., age, sex, molt, pregnancy status, pelage type). These data are most useful when combined in a relational manner with other datasets (e.g. telemetry, health and disease, morphometrics).

This dataset is from a study examining the growth responses of juvenile walleye pollock at ambient and 3 elevated CO2 levels.

2007 Bering Sea walleye pollock larvae condition data set. Larvae collected 8- 14 May 2007.
Condition of larvae (healthy or unhealthy) was determined using the model described in Porter, S.M., and K.M. Bailey. 2011. Assessing the condition of walleye pollock Theragra chalcogramma (Pallas) larvae using muscle-based flow cytometric cell cycle analysis. J. Exp. Mar. Biol. Ecol. 399:101-109.

Allozyme variation was used to examine population genetic structure of adult chinook salmon, Oncorhynchus tshawytscha, collected between 1988 and 1993 from 22 spawning locations in Southeast Alaska and northern British Columbia. Thirty-five loci and two pairs of isoloci were variable, and of these, 25 loci and one pair of isoloci expressed the most abundant allele with a frequency of less than or equal to 0.95 in at least one collection. Aneighbor-joining (NJ) tree of genetic distances defined five regional groups: (1) King Salmon River (the only island collection), which has large allelic frequency differences from other populations in this study; (2) heterogeneous coastal populations from southern southeast Alaska; (3) transmountain collections from the Taku and Stikine Rivers on the eastern side of the coastal mountain range; (4) Chilkat River in northern Southeast Alaska; and (5) northern coastal Southeast Alaska, which consists of the Situk River and the Klukshu River, a tributary of the Alsek River. A second NJ tree that included collections from the Yukon River and British Columbia did not reveal any strong genetic similarity between Southeast Alaska and the Yukon River. The data suggest that Southeast Alaska may have been colonized from both northern and southern refugia following the last glaciation b?? a period of sufficient time to allow for isolation by distance to occur.

The data from this study, describes embryo development in Golden king crab, Lithodes aequispinus. Six female multiparous golden king crab were captured from the Aleutian Islands, Alaska, and mated in the laboratory. Their embryos were photographed and staged on average once every 9 days throughout embryogenesis.

This dataset contains information regarding the sighting and capture of Steller sea lions marked in Alaska from 1987 to 2014. Marks are seen and documented in a variety of ways; remote cameras, dedicated vessel- and land-based surveys, recaptures of Steller sea lions, aerial survey photographs, strandings, and opportunistic sightings sent in from the public.

Maternal effects on the quality of progeny can have direct impacts on population productivity. Rockfish are viviparous and the oil globule size of larvae at parturition has been shown to have direct effects on time until starvation and growth rate. We sampled embryos and preparturition larvae opportunistically from 89 gravid quillback rockfish (Sebastes maliger) in Southeast Alaska. Because the developmental stage and sampling period were correlated with oil globule size, they were treated as covariates in an analysis of maternal age, length, and weight effects on oil globule size. Maternal factors were related to developmental timing for almost all sampling periods, indicating that older, longer, and heavier females develop embryos earlier than younger, shorter, or lighter ones. Oil globule diameter and maternal length and weight were statistically linked, but the relationships may not be biologically significant. Weight-specific fecundity did not increase with maternal size or age, suggesting that reproductive output does not increase more quickly as fish age and grow. Age or size truncation of a rockfish population, in which timing of parturition is related to age and size, could result in a shorter parturition season. This shortening of the parturition season could make the population vulnerable to f luctuating environmental conditions.

This dataset contains information regarding the capture and tagging of northern fur seals on the Pribilof Islands and Bogoslof Island, Alaska, from 1992 to 2017. Cite dataset as: Alaska Ecosystems Program. 2019. Alaska northern fur seal tag data, 1992-2017. NOAA Fisheries Open Data Portal. https://noaa-fisheries-afsc.data.socrata.com/Species/Alaska-Northern-Fur-Seal-Tag-Data-1992-2017/nvhy-vag6