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
  • Feedback

    • Bering Sea Helicopter Surveys for Ice-Associated Seals (2007-08)

    Metadata Updated: May 1, 2024

    In the spring of 2007 and 2008, researchers from the Alaska Fisheries Science Center conducted aerial surveys for ribbon, bearded, and spotted seals in the US sector of the Bering Sea. The surveys were conducted from helicopters based aboard the US Coast Guard icebreakers Healy and Polar Sea. Line transect surveys were conducted between approximately 09:00 and 16:00 (local solar time), which corresponds to the timing of peak seal haul-out probability. By local solar time, we mean that for each 15° of latitude west of 0 degrees longitude, one hour was subtracted; thus, we used UTC minus 11 h for Bering Sea observations which puts the sun overhead at approximately noon at these coordinates. Each flight had two to three observers and was flown at a target altitude of 118m (400 ft) at speeds of 80–95 knots. Only seals hauled out on ice were observed and recorded. The distance from each seal to the helicopter’s track line was calculated using a sighting bar mounted on each observer’s window. In all, 2214 seals were observed during approximately 73 h of survey effort covering 11819 km of survey line on 63 flights. Because ice conditions decayed markedly toward the end of the 2007 surveys, our analysis used only the first 27 flights. The number of ringed seal sightings was low, possibly due to a combination of a preponderance of survey effort away from near-shore areas favored by ringed seals and a greater tendency for ringed seals to be disturbed into the water by the helicopter, and therefore to be missed by observers.

    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 17, 2024
    Metadata Created Date May 1, 2024
    Metadata Updated Date May 1, 2024
    Reference Date(s) (publication)
    Frequency Of Update notPlanned

    Metadata Source

    Harvested from NMFS AFSC

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Date April 17, 2024
    Metadata Created Date May 1, 2024
    Metadata Updated Date May 1, 2024
    Reference Date(s) (publication)
    Responsible Party (Point of Contact, Custodian)
    Contact Email
    Guid gov.noaa.nmfs.inport:17354
    Access Constraints Cite As: Alaska Fisheries Science Center, [Date of Access]: Bering Sea Helicopter Surveys for Ice-Associated Seals (2007-08) [Data Date Range], https://www.fisheries.noaa.gov/inport/item/17354., Access Constraints: The data set is in the process of being archived with the NOAA National Centers for Environmental Information. Once the archival process is complete and verified, the data set will be publicly available., Use Constraints: User must read and fully comprehend the metadata prior to use. Applications or inferences derived from the data should be carefully considered for accuracy. While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, 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. Acknowledge NOAA/NMFS/AFSC or the specified citation as the source from which these data were obtained in any publications and/or other representations of these data. Communication and collaboration with dataset authors is strongly encouraged., Distribution Liability: While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, 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.
    Bbox East Long -165
    Bbox North Lat 66
    Bbox South Lat 55
    Bbox West Long -180
    Coupled Resource
    Frequency Of Update notPlanned
    Harvest Object Id 66bbc079-dd52-443c-991c-88679ef9af37
    Harvest Source Id 26a29bb9-50b0-47fd-920b-edc74aa6ec76
    Harvest Source Title NMFS AFSC
    Licence NOAA provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. It is the responsibility of the user to determine whether or not the data is suitable for the intended purpose.
    Lineage All observers recorded information on the species, group size, and distance from the helicopter track line for each sighting via audio recording. Audio recordings were transcribed and sightings were time-synced and geo-referenced to a GPS track from each flight.
    Metadata Language eng
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-180.0, 55.0], [-165.0, 55.0], [-165.0, 66.0], [-180.0, 66.0], [-180.0, 55.0]]]}
    Progress completed
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 2008-04-06
    Temporal Extent End 2008-04-27

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