Fish and invertebrates that are unintentionally captured during commercial fishing operations and then released back into the ocean suffer mortality at unknown rates, introducing uncertainty into the fishery management process. Attempts have been made to quantify discard mortality rates using reflex action mortality predictors or RAMP which use the presence or absence of a suite of reflexes to predict discard mortality. This method was applied to Tanner crab, Chionoecetes bairdi, during the 2010-2012 fisheries in the Bering Sea. Discard mortality in the fishery is currently assumed to be 50% in stock assessment models, but that rate is not based on empirical data and is widely recognized to be in need of refinement. Over 19,000 crab were evaluated using the RAMP method. The estimated discard mortality rate was 4.5% (SD = 0.812), significantly below the rate used in stock assessment models. Predicted discard mortality rates from the 2010-2012 study were strongly correlated with the air temperature at the St. Paul Island airport in the Pribilof Islands. Using this relationship the discard mortality rate from 1991-2011was estimated at 4.2% (SD = 1.08).

Scientists at the Auke Bay Laboratory have conducted marine debris surveys on select beaches in Alaska periodically since 1972. Some of the beaches previously sampled have been identified as marine debris hot spots due to their increased debris accumulation. At each location, multiple 1 km beach segments were sampled by people walking the beach and enumerating all anthropogenic marine debris found. The beach area surveyed was from the waters edge up to the base of the storm berm or log piles. Individual beach segments have been walked multiple times in the since 1972 allowing for a direct comparison with prior years. Sampling occurred in late spring and summer to test the hypothesis of change in marine debris sources due to increased summer boat traffic and the diminished occurrence and severity of storms.

The Resource Assessment and Conservation Engineering Division (RACE) of the Alaska Fisheries Science Center (AFSC) conducts bottom trawl surveys to monitor the condition of the demersal fish and crab stocks of Alaska. These data include catch per unit effort for each commercially important crab species at a standard set of stations in the eastern Bering Sea. This is a subset of the main database. Excluded are certain non standard tows and other types of data collected other than species id, species size category, species catch per unit effort (number per square nautical mile), water temperature and depth.

This dataset contains detailed crab data collected from the annual NOAA/NMFS/AFSC/RACE crab-groundfish bottom trawl survey of the eastern Bering Sea continental shelf. The standard survey area, surveyed each year since 1975, encompasses a major portion of the eastern Bering Sea shelf between the 20 meter and 200 meter isobaths and from the Alaska Peninsula to the north of St. Matthew Island. The study area is divided into a grid with cell sizes of 20 x 20 nautical miles (37 x 37 kilometers). Sampling takes place within each 20 x 20 nautical mile grid cell. In areas surrounding St. Matthew (1983-present) and the Pribilof Islands (1981-present), grid corners were also sampled to better assess king crab concentrations. In 1975, tows were 1 hour in duration; from 1976 to present, each tow is one-half hour in duration, averaging 1.54 nautical miles (2.86 kilometers) - exact tow duration and distance fished for each haul can be found in RACEBASE.HAUL. 100% of the catch is sorted for red, blue, and golden king crab, bairdi Tanner, snow crab, hybrid Tanner, and hair crab. Crabs are sorted by species and sex, and a sample is measured to the nearest millimeter to provide a size-frequency distribution (see note under use constraints for analyzing catches where crab were subsampled for measurement). Carapace width is measured for Tanner crabs, and carapace length is measured for king and hair crabs.

This dataset contains crab data from a field survey of Chionoecetes bairdi and C. opilio collected at six designated index sites in the Bering Sea during the 2015 NOAA/NMFS/AFSC/RACE crab-groundfish bottom trawl surveys of the eastern Bering Sea. Each of the six index sites were made up of approximately 10 survey stations and chosen based on historical incidences of the parasite Hematodinium sp., the causative agent of Bitter Crab Syndrome (BCS). 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) to evaluate any changes in intensity of disease within the index sites that may provide information as to how the disease is moving or changing within EBS crab populations. The data includes sampling year, index site, species, crab morphometrics, Hematodinium sp. parasite presence/absence based on PCR assay results.

Scientists at the Auke Bay Laboratory have conducted marine debris surveys on select beaches in Alaska periodically since 1972. Some of the beaches previously sampled have been identified as marine debris hot spots due to their increased debris accumulation. At each location, multiple 1 km beach segments were sampled by people walking the beach and enumerating all anthropogenic marine debris found. The beach area surveyed was from the waters edge up to the base of the storm berm or log piles. Individual beach segments have been walked multiple times in the since 1972 allowing for a direct comparison with prior years. Sampling occurred in late spring and summer to test the hypothesis of change in marine debris sources due to increased summer boat traffic and the diminished occurrence and severity of storms.

d15N and d13C isotopic ratios from multiple groundfish and groundfish prey samples collected on groundfish surveys and by fishery observers onboard commercial fishing vessels in the eastern Bering Sea, and Gulf of Alaska from 2006 through 2008 via NPRB project, NPRB.2006.22.Isotopes, and continued by AFSC.

This project genetically analyzed 1,620 chinook salmon samples from the 2009 spring salmon excluder device test. These samples were collected over a short period of time from a limited geographical area and thus represent a unique sample set.

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.

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