This dataset supports efforts to estimate the abundance and trends in population size of Alaska harbor seals. Annual surveys of harbor seal populations are fundamental to estimation of seal abundance, distribution, and trends, which in turn are essential for stock assessment, conservation, and management. The most feasible approach to determining harbor seal distribution and abundance is to use aircraft to count seals when they haul out of the water and are visible. Harbor seals in Alaska occupy a geographically extensive range from approximately long. 172ºE to 130ºW (over 3,500 km east to west) and from lat. 51ºN to 61.5ºN (over 1,000 km north to south). Estimation of the abundance of harbor seals statewide requires broad-scale aerial surveys and these surveys have been conducted by NOAA Fisheries, the Alaska Department of Fish and Game, and other collaborators since the early 1980s. This dataset reflects counts of harbor seals from surveys conducted in Alaska between 1998 and 2002.

Effort data collected by observers in the United States commercial groundfish fisheries of Alaska (Bering Sea, Aleutian Islands and Gulf of Alaska, 1993-2017.
Subset of the Alaska observer groundfish data, aggregating by 400km square cells and eliminating cells with less than three vessels to create a public version of the Alaska groundfish observer data.
Purpose: Allows visitors use of the aggregated observer data to create maps. These maps are designed to provide a better understanding of where groundfish are caught in the Aleutian Islands, Bering Sea and Gulf of Alaska.
Supplemental_Information: http://www.afsc.noaa.gov/FMA/fma_database.htm
Number 5 of a set of 5 files:
1. AFSC/FMA: North Pacific Groundfish and Halibut Observer Program Fishery Statistics - Rockfish Catch
2. AFSC/FMA: North Pacific Groundfish and Halibut Observer Program Fishery Statistics - Flatfish Catch
3. AFSC/FMA: North Pacific Groundfish and Halibut Observer Program Fishery Statistics - Most fishes (excluding flatfishes and rockfishes) Catch
4. AFSC/FMA: North Pacific Groundfish and Halibut Observer Program Fishery Statistics - Invertebrates Catch
5. AFSC/FMA: North Pacific Groundfish and Halibut Observer Program Fishery Statistics - Effort Statistics

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 a collection of morphometrics obtained from all of these species across a variety of research projects. Morphometric data were collected from seals that were captured and sampled in the north Pacific, Bering and Chukchi Seas, in 2004-2012, 2014, 2015. There are also morphometric data from ribbon, spotted, and bearded seals that were collected during a research cruise in 1991. Data collected include lengths, girths, mass, and blubber thickness.

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.

This dataset contains crab data from a field survey of Chionoecetes spp. collected during the 2016 NOAA/NMFS/AFSC/RACE groundfish and invertebrate resources bottom trawl survey of the eastern Bering Sea continental slope (EBSS). Crabs were taken opportunistically, at any station regardless of location and depth, and at random. Blood samples were taken from collected crab using non-lethal methods and were preserved in 100% ethanol. Samples were tested in a laboratory with a DNA test to detect the presence of the parasite Hematodinium sp., the causative agent of Bitter Crab Syndrome (BCS). The data includes sampling year, sampling station information, species, crab morphometrics, Hematodinium sp. parasite presence/absence based on PCR assay results.

Juvenile red and blue king crabs (Paralithodes camtschaticus and P. platypus) were exposed to three pH levels: ambient (pH 8.1), pH 7.8, and pH 7.5 for three weeks. Oxygen consumption and feeding ration were determined immediately after exposure to treatment water and after three weeks exposure. Growth can be calculated from the wet mass observations.

To study the effects of ocean acidification we examined the effects of ocean acidification on the embryo and larval stages of the economically important southern Tanner crab, Chionoecetes bairdi. Ovigerous females were reared in one of 3 treatments: control (ambient pH ~8.1), pH 7.8, and pH 7.5 for 2 years. Embryos and larvae in year 1 were from oocytes developed in the field whereas embryos and larvae in year 2 were from oocytes developed under acidified conditions Larvae hatched each year, were also exposed to 3 pH treatments to examine starvation-survival, morphology, condition, and calcium/magnesium content. The carbonate chemistry data included salinity, temperature, pH, alkalinity, dissolved inorganic carbon, CO2, bicarbonate, carbonate, and the saturation states of aragonite and calcite. These values varied according to treatment and season throughout the study.

Aerial surveys were conducted during 1983–2006 in the Ketchikan, Sitka, Kodiak, and Bristol Bay areas of Alaska to estimate trends in abundance of harbor seals.

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.