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.

The core function of the Resource Assessment and Conservation Engineering (RACE) Division is to conduct quantitative fishery surveys and related ecological and oceanographic research to measure and describe the distribution and abundance of commercially important fish and crab stocks in the eastern Bering Sea, Aleutian Islands, and Gulf of Alaska. This includes measuring the abundance of fish (including rockfishes) in rocky untrawlable areas. To accomplish this, we are mapping untrawlable areas using an ME70 multibeam data. These data area stored as image files ArcGIS shapefiles

We assembled 1.75 million National Ocean Service (NOS) bathymetric soundings from 225 lead-line and single-beam echosounder hydrographic surveys conducted from 1901 to 1999 in the central Gulf of 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 Our editing included deleting erroneous and superseded values, digitizing missing values, and properly aligning all data sets to a common, modern datum. There were several areas where these older surveys were superseded by more recent, higher quality multibeam surveys, mostly from the NOS (n=106). Three of these were unprocessed NOS multibeam surveys in the Sitka area, which we edited and processed into final bathymetric surfaces. We reduced the resolution of these multibeam surveys to 100 m, since some may have sub-meter resolution and many exceed a million soundings, and added them to our bathymetry compilation. We proofed, edited or digitized 96,000 cartographic features (mostly from the smooth sheets, some from the multibeam surveys), such as rocky reefs, kelp beds, rocks and islets, creating the most thorough source of these typically shallow, inshore features. The depth surface and inshore features, available at the Alaska Fisheries Science Center (AFSC: http://www.afsc.noaa.gov), were mostly produced at a map scale of 1:20,000.

The dataset contains trawl and seine catches from Southeast Alaskan estuaries sampled from 1995 to 2008. The data also include physical variables (temp, salinity, turbidity), and shorezone shoreline classifications.

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.

We assembled 1.75 million National Ocean Service (NOS) bathymetric soundings from 225 lead-line and single-beam echosounder hydrographic surveys conducted from 1901 to 1999 in the central Gulf of 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. There were several areas where these older surveys were superseded by more recent, higher quality multibeam surveys, mostly from the NOS (n=106). Three of these were unprocessed NOS multibeam surveys in the Sitka area, which we edited and processed into final bathymetric surfaces. We reduced the resolution of these multibeam surveys to 100 m, since some may have sub-meter resolution and many exceed a million soundings, and added them to our bathymetry compilation. Survey H11354 was missing in the entrance to Sitka Sound. Processing and adding its bathymetric data to our compilation filled in a substantial gap in Sitka area.

Diel epipelagic sampling for juvenile Pacific salmon (Oncorhynchus spp.), rockfish (Sebastes spp.), sablefish (Anoplopoma fimbria), and associated species was conducted in order to identify factors that may affect year-class success of these commercially important species. Sampling occurred in offshore marine habitats of the coastal northeast Pacific Ocean from 10-20 August 2005 and was conducted with a surface trawl fishing the upper 20 m of the water column along transects up to78 km offshore near 58 N. Three habitats were sampled along each transect over a 24-hr period: the continental shelf (<200 m depth), the continental slope (400-750 m depth), and the abyss (>2,000 m depth). A total of 38,747 fish and squid representing 24 species were sampled in 56 trawl hauls. Of the targeted juvenile fish species, a total of 587 salmon, 11 rockfish, and 70 sablefish were captured. Sampling during day (1500-1900) and night (2200-0200) periods indicated that biomass of fish and squid was 2-4 times higher at night at (each?)all habitat types pooled across transects. No distinct patterns between day or night occurrence were noted for juvenile pink salmon (O. gorbuscha), chum salmon (O. keta), sockeye salmon (O. nerka), or coho salmon (O. kisutch), however, juvenile Chinook salmon (O. tshawytscha) were encountered only at night. Catches of juvenile rockfish and juvenile sablefish were quite low in this study, and larger sample sizes of these fish are needed to adequately determine their diel distribution. Diel differences were apparent with forage species such as Pacific herring (Clupea pallasi), capelin (Mallotus villosus), and eulachon (Thaleichthys pacificus) that were almost exclusively sampled at night. The offshore distribution patterns of target species were distinctly different, with the most common occurrences of juvenile salmon over continental shelf habitats, juvenile sablefish over continental shelf and slope habitats, and juvenile rockfish over slope and abyss habitats. Pacific herring, capelin, eulachon, and Pacific sardines (Sardinops sagax) were found over continental shelf habitats, whereas small squid and myctophids occurred primarily at slope and abyssal habitats. The greatest overall catch biomass was of gelatinous species (jellyfish), which was consistently higher than that of all fish and squid combined, usually by an order of magnitude. Individual fish or squid species with highest average weight per haul were pomfret (Brama japonica), adult coho salmon, Humboldt squid (Dosidicus gigas), and blue sharks (Prionace glauca). The occurrence of the latter two warm-water species and Pacific sardines were of interest because this study occurred during an anomalously warm year and the capture of Pacific sardines and Humboldt squid represent northern range extensions for these species. Stomach content analysis of potential predator species of the target species showed that only adult coho salmon were predating on juvenile salmon and sablefish, and only pomfret were predating on juvenile rockfish. Further sampling of the target species is needed in these habitats during more normal environmental conditions to validate these observations.

A comprehensive species list of marine invertebrates of Alaska has been lacking. The checklist of Austin (1985) treated the marine invertebrates of the southern coast of Alaska to California and since then many new species have been described, many range extensions have been discovered, and considerable changes in higher-level systematics have been made. The checklist we compiled lists over 3,500 species and includes the currently accepted scientific name and its significant synonyms, common names, type localities, geographic and depth distributions, a general statement of abundance in Alaska when known (e.g., rare, uncommon, common, abundant), and general remarks. This checklist will serve as a foundation for future species-specific research. Updated species lists are necessary to reflect the current state of biodiversity knowledge and are thus essential for conservation planning and management. To monitor and predict future changes to marine life, the distribution and abundance of marine species need to be better understood, and this can only be achieved with reliable identifications based on a sound taxonomy. The current status and future directions of Alaskan marine invertebrate biodiversity are briefly discussed.

We assembled 1.75 million National Ocean Service (NOS) bathymetric soundings from 225 lead-line and single-beam echosounder hydrographic surveys conducted from 1901 to 1999 in the central Gulf of 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. There were several areas where these older surveys were superseded by more recent, higher quality multibeam surveys, mostly from the NOS (n=106). Three of these were unprocessed NOS multibeam surveys in the Sitka area, which we edited and processed into final bathymetric surfaces. We reduced the resolution of these multibeam surveys to 100 m, since some may have sub-meter resolution and many exceed a million soundings, and added them to our bathymetry compilation. In Sitka Sound survey H11118 was missing. Processing and adding its bathymetric data to our compilation filled in a substantial gap in Sitka area, between Kruzof, Krestof, and Middle islands.

We assembled 1.75 million National Ocean Service (NOS) bathymetric soundings from 225 lead-line and single-beam echosounder hydrographic surveys conducted from 1901 to 1999 in the central Gulf of 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. There were several areas where these older surveys were superseded by more recent, higher quality multibeam surveys, mostly from the NOS (n=106). Three of these were unprocessed NOS multibeam surveys in the Sitka area, which we edited and processed into final bathymetric surfaces. We reduced the resolution of these multibeam surveys to 100 m, since some may have sub-meter resolution and many exceed a million soundings, and added them to our bathymetry compilation. In Sitka Sound was missing survey H11114. Processing and adding its bathymetric data to our compilation filled in a substantial gap in Sitka area, between Kruzof and Krestof islands.