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    • EK60 Water Column Sonar Data Collected During DY1803

    Metadata Updated: June 9, 2023

    Acoustic-Trawl Surveys of Walleye Pollock (Gadus chalcogrammus) in the Gulf of Alaska (DY1803, EK60). The Midwater Assessment and Conservation Engineering (MACE) program of NOAA Fisheries, Alaska Fisheries Science Center (AFSC) conducted acoustic-trawl (AT) stock assessment surveys in the Shelikof Strait and Marmot Bay areas of the Gulf of Alaska (GOA) in the late winter/early spring of 2018 to estimate the distribution and abundance of walleye pollock (Gadus chalcogrammus). This survey was conducted aboard NOAA Ship Oscar Dyson, a 64 meter stern trawler equipped with acoustic and oceanographic instrumentation. The primary acoustic instrument for the survey was a Simrad EK60 split-beam echosounder system utilizing five frequencies (18, 38, 70, 120, and 200 kHz). The vessel conducted an acoustic system calibration in Captains Bay, Dutch Harbor, Alaska on 12 March and departed Dutch Harbor on 13 March transiting toward Shelikof Strait. The Shelikof Strait survey was conducted 15-21 March followed by the Marmot Bay survey 21-22 March. A post-cruise calibration of the echosounder system was conducted at the end of the cruise on 23 March in Kalsin Bay, Kodiak Island, Alaska. The vessel returned to its homeport of Kodiak, Alaska on 23 March ending the cruise.

    Access & Use Information

    License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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    Dates

    Metadata Date September 14, 2021
    Metadata Created Date November 10, 2022
    Metadata Updated Date June 9, 2023
    Reference Date(s) March 12, 2018 (creation), May 30, 2019 (publication)
    Frequency Of Update notPlanned

    Metadata Source

    Harvested from NGDC MGG Sonar Water Column

    Other Data Resources

    Additional Metadata

    Resource Type Series
    Metadata Date September 14, 2021
    Metadata Created Date November 10, 2022
    Metadata Updated Date June 9, 2023
    Reference Date(s) March 12, 2018 (creation), May 30, 2019 (publication)
    Responsible Party NOAA National Centers for Environmental Information (Point of Contact)
    Contact Email
    Guid gov.noaa.ncei.wcd:DY1803_EK60
    Access Constraints Cite as: NOAA Alaska Fisheries Science Center. 2018. 'EK60 Water Column Sonar Data Collected During DY1803'. NOAA National Centers for Environmental Information. https://doi.org/10.25921/8p86-5z92 [access date], Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives., Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose., Resource may not be available for up to one year after initial collection.
    Bbox East Long -151.62942
    Bbox North Lat 58.75208
    Bbox South Lat 53.86998
    Bbox West Long -166.60061
    Coupled Resource
    Frequency Of Update notPlanned
    Harvest Object Id dd306835-ebd8-497d-969d-98128d60e1ba
    Harvest Source Id ab8b0290-e4db-4a00-89f2-4e427c2054b2
    Harvest Source Title NGDC MGG Sonar Water Column
    Licence These data are considered raw and have not been subjected to the NOAA's quality control or quality assurance procedures. They are released for limited public use as preliminary data to be used only with appropriate caution. NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty., Not subject to copyright protection within the United States.
    Lineage Calibrated w/ calibration data
    Metadata Language eng; USA
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-166.60061, 53.86998], [-151.62942, 53.86998], [-151.62942, 58.75208], [-166.60061, 58.75208], [-166.60061, 53.86998]]]}
    Progress completed
    Spatial Data Service Type
    Spatial Reference System urn:ogc:def:crs:EPSG::4326
    Spatial Harvester True
    Temporal Extent Begin 2018-03-12T16:18:09
    Temporal Extent End 2018-03-24T01:52:11

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