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.

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 database contains information about shrimp surveys conducted by the National Marine Fisheries Service and the Alaska Department of Fish and Game in the Gulf of Alaska, Bering Sea and Aleutian Islands dating back to 1953. The main tables used for analysis are the shrimp.catch, shrimp.length, shrimp.cruise, and shrimp.haul tables. Join columns provide linkages between the tables.The shrimp.catch table contains catch weights and counts by haul. Not all catch weights have associated counts and in the earlier years of the time series the catch of all species was not recorded so care must be taken that a non-recorded catch is not interpretated as a zero catch. The shrimp.length table contains the length measurements of the shrimp and other taxa taken during the smallmesh survey.The Shrimp.cruise table contains information on each of the individual surveys called cruises included in the smallmesh database from the Bering Sea, Gulf of Alaska, and Aleutian Islands. The definition of a cruise has not been consistent over the years. Generally, a cruise is conducted by a single vessel in a single geographic area. For certain cruises however, multiple vessels participated in hauls ranging from the Bering Sea to the Gulf of Alaska. The records from some cruises contain as few as one haul while several consist of over 500 hauls. The Shrimp.haul table contains the basic information gathered for each haul including location, date and time, and gear information. Some of the hauls in the data set are from surveys not necessarily targeting shrimp, mainly the hauls in the Bering Sea and Aleutian Islands.

In December of 2009, a total of 135 adult male red king crab (Paralithodes camtschaticus) were tagged with depth and temperature recording archival tags and released in eastern Bering Sea for the purpose of tracking their seasonal migrations. A total of 2 crab were recaptured by the commercial fishery after being at liberty for 315 and 330 days

The Northern Shrimp Survey was initiated in 1983 by the Atlantic States Marine Fisheries Commission (ASMFC) and monitors the relative abundance (number of shrimp), biomass (weight of shrimp), and composition of the northern shrimp stock throughout the Gulf of Maine. The data give an understanding of year class strength and sex stage and maturity of shrimp in the population. The survey focuses its efforts in offshore waters (in depths greater than 50 meters) and is timed to sample both males and females during the summer when they are expected to be offshore. The data it collects forms the basis of the annual northern shrimp assessment, which in turn, is used by fishery managers from Maine, New Hampshire and Massachusetts to set each year’s fishing regulations.

We assembled 1.4 million National Ocean Service (NOS) bathymetric soundings from 98 lead-line and single-beam echosounder hydrographic surveys conducted from 1910 to 1999 in Cook Inlet, Alaska. These bathymetry data are available from the National Geophysical Data Center (NGDC: http://www.ngdc.noaa.gov), which archives and distributes data that were originally collected by the NOS and others. While various bathymetry data have been downloaded previously from NGDC, compiled, and used for a variety of projects, our effort differed in that we compared and corrected the digital bathymetry by studying the original analog source documents - digital versions of the original survey maps, called smooth sheets. Our editing included deleting erroneous and superseded values, digitizing missing values, and properly aligning all data sets to a common, modern datum. There were six areas where these older surveys were superseded by compilations of reduced-resolution multibeam surveys. We digitized 12,000 features, such as rocky reefs, kelp beds, rocks and islets, adding them to what was originally available, and creating the most thorough source (n = 18,000) of these typically shallow, inshore features. We also digitized 2,418 km of the mainland and 529 km of island shoreline, generally at a resolution of 1:20,000, and digitized 9,271 verbal surficial sediment descriptions from the smooth sheets. The depth surface, shoreline, inshore features, and sediment data sets are mostly produced at a scale of 1:20,000.

These are data from a laboratory experiment in which wild caught male Tanner crab (Chionoecetes bairdi) from Stephens Passage, SE Alaska were held to evaluate crab survival while harboring Hematodinium sp., a parasitic dinoflagellate and causative agent of Bitter Crab Syndrome (BCS). In October 2014, Tanner crab in various condition states were targeted and collected. Targeted crab condition states were visually healthy, visually BCS positive or questionably BCS positive. Crab were held from capture until death (ongoing) and crab were tested regularly for parasite presence using two methods, blood smears and a PCR assay to detect the presence of parasite DNA. The data include crab morphometrics, disease status by diagnostic method, and crab survival duration.

From 1994 through 2012 Tanner crab were identified as premolt, held through a molt, and then measured to determine growth per molt.

We assembled 1.4 million National Ocean Service (NOS) bathymetric soundings from 98 lead-line and single-beam echosounder hydrographic surveys conducted from 1910 to 1999 in Cook Inlet, Alaska. These bathymetry data are available from the National Geophysical Data Center (NGDC: http://www.ngdc.noaa.gov), which archives and distributes data that were originally collected by the NOS and others. While various bathymetry data have been downloaded previously from NGDC, compiled, and used for a variety of projects, our effort differed in that we compared and corrected the digital bathymetry by studying the original analog source documents - digital versions of the original survey maps, called smooth sheets. Our editing included deleting erroneous and superseded values, digitizing missing values, and properly aligning all data sets to a common, modern datum. There were six areas where these older surveys were superseded by compilations of reduced-resolution multibeam surveys. We digitized 12,000 features, such as rocky reefs, kelp beds, rocks and islets, adding them to what was originally available, and creating the most thorough source (n = 18,000) of these typically shallow, inshore features. We also digitized 2,418 km of the mainland and 529 km of island shoreline, generally at a resolution of 1:20,000, and digitized 9,271 verbal surficial sediment descriptions from the smooth sheets. The depth surface, shoreline, inshore features, and sediment data sets are mostly produced at a scale of 1:20,000.

The GOA/AI Bottom Trawl Estimate database contains abundance estimates for the Alaska Biennial Bottom Trawl Surveys conducted in the Gulf of Alaska and the Aleutian Islands in alternate years. The estimates build upon raw and summary data available from the RACEBASE database and include calculated catch-per-unit-effort (cpue)s for principal species of groundfish and key invertebrates for each survey region. The cpues are averaged by survey strata, and then average cpues are multiplied by stratum areas which results in estimates of biomass and numerical abundance. Length and age data are combined with abundance to estimate the population at length and sex and population at age and sex.