Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Skip to content

EK80 Water Column Sonar Data Collected During DY2403

Metadata Updated: May 1, 2025

The Midwater Assessment and Conservation Engineering (MACE) program of NOAA Fisheries (NMFS), Alaska Fisheries Science Center (AFSC), conducted acoustic-trawl (AT) stock assessment surveys in the Shelikof Strait and Chirikof Shelf break areas of the Gulf of Alaska (GOA) 5-20 March, 2024, to estimate distribution and abundance of walleye pollock (Gadus chalcogrammus). The surveys were conducted aboard NOAA Ship Oscar Dyson (built in 2003, 64 meters, 2500 tons, 3100 hp), a research stern trawler equipped with acoustic and oceanographic instrumentation. The primary water column acoustic instrument for these surveys was a Kongsberg EK80 split-beam scientific echosounder system utilizing five frequencies (18, 38, 70, 120, and 200 kHz). The vessel departed Kodiak, Alaska on 5 March and conducted the Shelikof Strait survey 6-17 March, and the Chirikof Shelf break survey 17-19 March. A calibration of the EK80 echosounder system was conducted during a previous survey (DY2401) on 4 February in Kalsin Bay, Kodiak Island, Alaska, and a post-survey calibration was conducted in Uyak Bay, Kodiak Island, Alaska, on 9 March. Trawl operations were conducted using an LFS1421 mid-water trawl net equipped with a Kongsberg FS70 trawl sonar.

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.

Downloads & Resources

Dates

Metadata Date April 14, 2025
Metadata Created Date May 1, 2025
Metadata Updated Date May 1, 2025
Reference Date(s) March 5, 2024 (creation), April 14, 2025 (publication)
Frequency Of Update notPlanned

Metadata Source

Harvested from NGDC MGG Sonar Water Column

Additional Metadata

Resource Type Series
Metadata Date April 14, 2025
Metadata Created Date May 1, 2025
Metadata Updated Date May 1, 2025
Reference Date(s) March 5, 2024 (creation), April 14, 2025 (publication)
Responsible Party (Point of Contact); NOAA National Centers for Environmental Information (Point of Contact)
Contact Email
Guid gov.noaa.ncei:DY2403_EK80
Access Constraints Cite as: NOAA Alaska Fisheries Science Center. 2025. EK80 Water Column Sonar Data Collected During DY2403. NOAA National Centers for Environmental Information. https://doi.org/10.25921/xe4z-6h19 [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 -151.80039
Bbox North Lat 58.72451
Bbox South Lat 55.46343
Bbox West Long -157.08126
Coupled Resource
Frequency Of Update notPlanned
Harvest Object Id 0dac9636-6112-4ef7-905b-6b52a6b59317
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": [[[-157.08126, 55.46343], [-151.80039, 55.46343], [-151.80039, 58.72451], [-157.08126, 58.72451], [-157.08126, 55.46343]]]}
Progress completed
Spatial Data Service Type
Spatial Reference System urn:ogc:def:crs:EPSG::4326
Spatial Harvester True
Temporal Extent Begin 2024-03-05T00:00:00
Temporal Extent End 2024-03-20T11:59:59

Didn't find what you're looking for? Suggest a dataset here.