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AFSC/MML: Eastern Bering Sea Beluga Whale Aerial Surveys, 1992-1995, 1999-2000

Metadata Updated: April 1, 2024

In 1992-95 and 1999-2000, the U.S. Government provided funds for the Alaska Beluga Whale Committee (ABWC) to conduct studies of belugas in Alaska. Part of the ABWC research program consisted of aerial surveys of western Alaska beluga stocks, including the Eastern Bering Sea (EBS) stock. In 1992, several aerial surveys were conducted during three periods: 27-29 May, 17-21 June, and 18-22 September to assess the distribution of belugas during those periods. The surveys found relatively few belugas in May and September, but a large number of belugas in June. Based on those results, surveys in subsequent years were conducted only in June: 14-18 June 1993, 11-16 June 1994, 5-8 and 20-22 June 1995, 15-17 June 1999, and 17-20 June 2000. This dataset contains aerial survey data from the surveys described above.

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


Metadata Date February 29, 2024
Metadata Created Date December 9, 2022
Metadata Updated Date April 1, 2024
Reference Date(s) 2022 (creation), (publication)
Frequency Of Update notPlanned

Metadata Source

Harvested from NMFS AFSC

Additional Metadata

Resource Type Dataset
Metadata Date February 29, 2024
Metadata Created Date December 9, 2022
Metadata Updated Date April 1, 2024
Reference Date(s) 2022 (creation), (publication)
Responsible Party (Point of Contact, Custodian)
Contact Email
Guid gov.noaa.nmfs.inport:67735
Access Constraints Cite As: Alaska Fisheries Science Center, [Date of Access]: AFSC/MML: Eastern Bering Sea Beluga Whale Aerial Surveys, 1992-1995, 1999-2000 [Data Date Range],, Access Constraints: There are no legal restrictions on access to the data. They reside in public domain and can be freely distributed., Use Constraints: Users must read and fully comprehend the metadata prior to use. Applications or inferences derived from the data should be carefully considered for accuracy. These data undergo periodic updates as new data become available or existing data are edited for accuracy and consistency. To ensure that users have the most current version and to prevent duplication of, and encourage more efficient coordination with, any ongoing analyses, please contact Dr Megan Ferguson ( if there is an intention to use these data in a scientific report, whether published or not. Credit should always be given for any use of these data; please ask Dr Ferguson for the appropriate credits relative to the intended use. These data should be acquired from either National Centers for Environmental Information (NCEI) or MML and not through other sources that might not have the most recent version., 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 -156.6493
Bbox North Lat 66.367
Bbox South Lat 58.382
Bbox West Long -166.3412
Coupled Resource
Frequency Of Update notPlanned
Harvest Object Id c34756ab-0644-40bc-bc15-a25a844a313a
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 The survey was designed to cover coastal and offshore waters of Norton Sound and the Yukon Delta. Coastal transects were parallel to the shoreline with the centerline of the aircraft approximately 0.9 km offshore. Offshore transects were flown east to west along lines of latitude, north to south along lines of longitude, or on diagonals when travelling to and from airports. An adaptive sampling design was used in 1992 to 1995 to increase survey effort in areas where belugas had been sighted. When the belugas were seen on an offshore transect, additional parallel transects were flown at a 3.6-9.3 km spacing on both sides of the original line. Parallel transects were continued as long as belugas were seen, and usually stopped after two transects if there were no sightings. In 1999 and 2000, the survey was designed to cover all of Norton Sound and the Yukon River mouth with east to west transects regularly spaced at 9.3 km intervals. The total length of survey transects flown during each survey period was limited by the aircraft time available. The completion of transects was sometimes limited by weather conditions, particularly fog or high winds, and in June 1999 ice cover was a factor. The survey aircraft was a high-wing, twin-engine Aero Commander equipped with bubble windows, based in Nome. The crew included the pilot, a data recorder in the right front seat, and two observers seated behind the pilot on the left and right sides of the aircraft. Survey altitude was usually 305m, and ground speed was 274 km/hr (150 knots) in 1992 and 220 km/hr (120 knots) in all other years except some transit lines were flown at 274 km/hr in 1994. Navigation was done by reference to landmarks and with a Global Positioning System. The survey was done in passing mode, where whales were counted while staying on effort on the trackline. On the coastal transects, all belugas visible along the survey track were counted. The 1992 surveys were conducted as strip transect surveys; for the offshore transects, observers counted whales within 915 m wide strips on each side of the aircraft. The strips were offset 305 m from the centerline to eliminate the blind spot under the plane. The 1993 to 95 and 1999 to 2000 surveys were conducted as line transect surveys; the offshore transects on each side of the aircraft were divided into seven zones and each beluga sighting was recorded in one of the zones. Inclinometers were used to delineate the inner and outer bounds of zones from 0 to 51 deg. In 1992 and 1993, sightings and other data were recorded on datasheets by observers in one-minute intervals and were then entered into a computer database. In 1994 to“1995 and 1999 to 2000, a computer-based data entry program was used, logging the locations and times for the beginning and end of transects, the position on transect every 1 minute, and the exact time and position of each sighting. Environmental data and sighting conditions were also recorded. Data fields with S at the beginning of the field title (e.g., SOBSNUM, SGROUPSIZ) indicate sighting-related fields. Data fields with W at the beginning of the field title (WCLOUD, WBEAUSTAT, etc.) indicate weather-related fields.
Metadata Language eng
Metadata Type geospatial
Old Spatial {"type": "Polygon", "coordinates": [[[-166.3412, 58.382], [-156.6493, 58.382], [-156.6493, 66.367], [-166.3412, 66.367], [-166.3412, 58.382]]]}
Progress completed
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True
Temporal Extent Begin 1992
Temporal Extent End 2000

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