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    • AFSC/MML: Acoustics short-term passive monitoring using sonobuoys in the Gulf of Alaska, Bering, Chukchi, and Western Beaufort Seas, Summer 2007-2018

    Metadata Updated: April 1, 2024

    The Marine Mammal Laboratory (MML) has conducted passive acoustic monitoring in the Gulf of Alaska, Bering, Chukchi, and Western Beaufort Seas to determine spatio-temporal distribution of marine mammals as well as environmental and anthropogenic noise. Species and sounds detected on sonobuoys include fin, blue, bowhead, humpback, killer, gray, minke, sperm, beluga, sei, and North Pacific right whales, walrus, ribbon and bearded seals, fish, and seismic airguns. This short-term passive acoustic monitoring was also used to locate vocalizing species of interest for photo-identification, tagging, and behavioral studies. Recordings are available since 2007 in the Bering Sea, since 2010 in the Chukchi and Beaufort Seas, and in 2013 and 2015 in the Gulf of Alaska. Both omnidirectional and DiFAR sonobuoys have been used. In one year (2009), sonobuoys were deployed opportunistically from an aerial survey plane. All sonobuoys were provided by the United States Navy (Naval Operational Logistics Support Center, Naval Surface Warfare Center, Crane Division, and the Office of the Assistant Secretary of the Navy).

    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 February 29, 2024
    Metadata Created Date October 28, 2022
    Metadata Updated Date April 1, 2024
    Reference Date(s) 2007 (creation), (publication)
    Frequency Of Update annually

    Metadata Source

    Harvested from NMFS AFSC

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Date February 29, 2024
    Metadata Created Date October 28, 2022
    Metadata Updated Date April 1, 2024
    Reference Date(s) 2007 (creation), (publication)
    Responsible Party (Point of Contact, Custodian)
    Contact Email
    Guid gov.noaa.nmfs.inport:17346
    Access Constraints Cite As: Alaska Fisheries Science Center, [Date of Access]: AFSC/MML: Acoustics short-term passive monitoring using sonobuoys in the Gulf of Alaska, Bering, Chukchi, and Western Beaufort Seas, Summer 2007-2018 [Data Date Range], https://www.fisheries.noaa.gov/inport/item/17346., Access Constraints: There are no legal restrictions on access to the data. They reside in public domain and can be freely distributed., 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. Acknowledgement of NOAA/NMFS/AFSC, as the source from which these data were obtained in any publications and/or other representations of these, data is suggested., Distribution Liability: The user is responsible for the results of any application of this data for other than its intended purpose. NOAA denies liability if the data are misused.
    Bbox East Long -149.5
    Bbox North Lat 73.5
    Bbox South Lat 53.5
    Bbox West Long 170.3
    Coupled Resource
    Frequency Of Update annually
    Harvest Object Id 1a48c251-9b36-4bec-a900-70f93d77259b
    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 A sonobuoy is a free-floating, expendable, short-term passive acoustic listening device that transmits signals in real time via VHF radio waves to a receiver on a vessel or aircraft. The hydrophone is suspended down from the surface float at a programmable depth. For the majority of deployments, modifications were made by tying or taping sections of the sonobuoy housing to prevent the main wire spool from deploying; the resulting deployment depth was then 24 m. Additional modifications involved replacement of the display battery. Three types of sonobuoys were used: omnidirectional only, DiFAR only, and programmable DiFAR/Omnidirectional. DiFAR (Directional Frequency Analysis and Recording) capable sonobuoys transmit signal bearing information along with the acoustic signal. If two or more DiFAR sonobuoys are deployed, cross-fixes can be obtained on a calling animal to determine its location. When in DiFAR mode, the maximum frequency is limited to 2.5 kHz; the omni-directional sonobuoys were deployed occasionally in omnidirectional mode to achieve full bandwidth when bearing information was not needed. The methods that follow apply from 2009 on; prior to 2009 a variety of equipment and methods were used (see www.data.boem.gov/PI/PDFImages/ESPIS/5/5243.pdf for further details). The signals transmitted from the sonobuoys were received by one of two antennas, an omnidirectional and a directional (Yagi) antenna. Both antennas were placed in the crow’s nest of the vessel with the directional antenna facing astern. The directional antenna was used primarily during transit when the sonobuoy behind the vessel, and the omnidirectional antenna was used for monitoring multiple sonobuoys simultaneously, or when the boat was idling at station. A switch located in the bridge next to the acoustic station was used to alternate between antennas depending on the direction of travel. The signals received by the shipboard antennas were pre-amplified (15dB; PV160VDA, Advanced Receiver Research, Burlington, VT), before being sent via cabling to three G39WSBe WinRadio sonobuoy receivers, then inputted into a MOTU brand Ultralite mk3 multi-channel external soundcard. The soundcard digitized the signal at a sampling rate of 48 kHz. The external soundcard was connected to a laptop computer where the recordings were monitored in real-time and simultaneously recorded to an external hard drive using ISHMAEL (Mellinger 2001) software. Directional bearing information of calls was obtained using DiFAR demultiplexing software and a custom MATLAB interface (Greeneridge Sciences, Inc. and Mark McDonald, Whale Acoustics). A GPS feed into the computer provided the ship’s position every minute, as well as the sonobuoy deployment location information, and time. A custom tracking and plotting program implemented in MATLAB (Catherine Berchok, MML) allowed for real-time plotting of the vessel and sonobuoy locations, as well as bearing and location coordinates of calling whales. Monitoring occurred in real time 24/7, with the majority of sonobuoys deployed every three hours during ship transits. Analysis of sonobuoy data was undertaken primarily during the cruise. An acoustic technician monitored the scrolling spectrograms of the recordings from each sonobuoy aurally as well as visually, and noted the species detected during its deployment, these are included in the data as detected (1), not-detected (0), or possibly detected (2). Further information can be obtained via the following publications: Crance et al. 2017, and Rone et al. 2012.
    Metadata Language eng
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[170.3, 53.5], [-149.5, 53.5], [-149.5, 73.5], [170.3, 73.5], [170.3, 53.5]]]}
    Progress underDevelopment
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 2007
    Temporal Extent End 2014

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