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Short Citation:
Alaska Fisheries Science Center, 2023: AFSC/REFM: Acoustic trawl cooperative survey near Shumagin Islands 2007-2013,

Item Identification

Title: AFSC/REFM: Acoustic trawl cooperative survey near Shumagin Islands 2007-2013
Short Name: AFSC/REFM: Acoustic trawl cooperative survey near Shumagin Islands 2007-2013
Status: Completed

In May of 2006, scientists from the Alaska Fisheries Science Center

participated in a pilot outreach program in Sand Point, Alaska. At the meetings,

fishermen raised a number of concerns about the adequacy of walleye pollock

(Theragra chalcogramma) assessment. The issues appeared to be related to the contrasting

observational scales of fishermen and National Marine Fisheries Service (NMFS) scientists

responsible for conducting assessment surveys and population modeling. NMFS resource

assessment surveys have a large spatial scale (i.e., the entire Gulf of Alaska) and occur

infrequently as they are biennial summer bottom trawl and acoustic-trawl surveys, with annual

or biennial winter acoustic-trawl surveys targeting key spawning

areas(von Szalay, et al. 2010; Guttormsen and Yasenak, 2007; Guttormsen and Jones, 2010).

The stock assessment model for pollock estimates stock abundance for the central and western

Gulf of Alaska (Dorn et al., 2011). In contrast, the observational scale of fishermen is spatially

restricted but temporally extensive, since they are on the water fishing throughout the year.

Fishermen questioned whether NMFS assessment activities were appropriately designed

to monitor the status of pollock in their area. They noted that additional surveys

in different seasons and a more comprehensive acoustic-trawl survey effort in winter

could help address seasonal issues such as movement between spawning and feeding areas.

Cooperative research projects with the Sand Point fishing community were identified

as a potential approach for addressing some of these issues, but fishermen wanted

the assurance that their investment of time and effort will lead to improvements

in stock assessment. The acoustic-trawl surveys described in this report resulted

from collaboration between NMFS scientists, the Aleutian East Borough, and local

fishermen to address issues raised during the outreach program. Acoustic-trawl

surveys were conducted from a local fishing vessel in the western Gulf of Alaska

during 2007-2013. To some extent, the surveys carried out during this period reflected

shifting program objectives. The initial objective was simply to demonstrate the

feasibility of using local fishing vessels to conduct acoustic-trawl surveys and

to collect acoustic and biological information sufficient to estimate walleye pollock

biomass and spatial pattern. Once this was demonstrated, the focus of the project expanded

to include other objectives. Specific objectives of the project

were the following:

Evaluate the feasibility of conducting acoustic-trawl surveys

of pollock using local fishing vessels.

Evaluate the quality of acoustic data collected from the Simrad ES60 echosounder.

Evaluate the appropriateness of the design of the current NMFS acoustic-trawl surveys

in the western Gulf of Alaska. Specific issues to be addressed included 1) transect density

in bathymetrically complex regions in the western Gulf of Alaska, 2) day/night differences

in pollock density, and 3) temporal variability of pollock density during replicate transects.

Evaluate the timing of the NMFS survey (mid-February) in Sanak Trough

by conducting a survey in January prior to the NMFS survey.

Evaluate relationships between adult pollock density, young-of-the-year pollock density,

euphausiid density, and the distribution of foraging humpback whales (Megaptera novaeangliae).

The estimates of abundance and distribution of walleye pollock were developed for

areas covered by cooperative acoustic-trawl surveys conducted aboard a fishing vessel

during alternate Septembers and Januarys between 2007-2013. Physical oceanographic

and biological composition observations, initial findings from ancillary data collections

of marine mammal observations, and dual-frequency differencing techniques to discriminate

different types of acoustic backscatter were also developed.


cooperative research, outreach


Loaded by FGDC Metadata Uploader, batch 5695, 03-24-2015 14:27

The following FGDC sections are not currently supported in InPort, but were preserved and will be included in the FGDC export:

- Taxonomy (FGDC:taxonomy)

- Lineage (FGDC:lineage)


Theme Keywords

Thesaurus Keyword
ISO 19115 Topic Category
ISO 19115 Topic Category
None abundance
None acoustic
None backscatter
None CTD
None line-transect survey

Temporal Keywords

Thesaurus Keyword
None fall
None winter

Spatial Keywords

Thesaurus Keyword
None Alaska
None Gulf of Alaska
None Shumagin Islands

Physical Location

Organization: Alaska Fisheries Science Center
City: Seattle
State/Province: WA
Country: USA

Data Set Information

Data Set Scope Code: Data Set
Maintenance Frequency: None Planned
Data Presentation Form: Map (digital)
Data Set Credit: Suzanne Romain, Vidar Wespestad

Support Roles

Data Steward

CC ID: 234318
Date Effective From: 2015-10-19
Date Effective To:
Contact (Person): Dorn, Martin
Address: 7600 Sand Point Way, NE
Seattle, WA 98115-6349
Email Address:


CC ID: 234319
Date Effective From: 2015-10-19
Date Effective To:
Contact (Organization): Alaska Fisheries Science Center (AFSC)
Address: 7600 Sand Point Way N.E., Building 4
Seattle, WA 98115
Business Hours: 0700-1700 Pacific Time

Metadata Contact

CC ID: 194815
Date Effective From: 2015-03-24
Date Effective To:
Contact (Person): MC, Metadata Coordinators
Email Address:


CC ID: 194817
Date Effective From: 2015-03-24
Date Effective To:
Contact (Person): Dorn, Martin
Address: 7600 Sand Point Way, NE
Seattle, WA 98115-6349
Email Address:


CC ID: 194818
Date Effective From: 2015-03-24
Date Effective To:
Contact (Organization): Alaska Fisheries Science Center (AFSC)
Address: 7600 Sand Point Way N.E., Building 4
Seattle, WA 98115
Business Hours: 0700-1700 Pacific Time

Point of Contact

CC ID: 194816
Date Effective From: 2015-03-24
Date Effective To:
Contact (Person): Dorn, Martin
Address: 7600 Sand Point Way, NE
Seattle, WA 98115-6349
Email Address:


Currentness Reference: Ground Condition

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 194814
W° Bound: -162.3
E° Bound: -160
N° Bound: 55.4
S° Bound: 54.4

Shumagin Islands to Sanak Islands, AK

Extent Group 1 / Time Frame 1

CC ID: 194813
Time Frame Type: Range
Start: 2007
End: 2013

Access Information

Security Class: Unclassified
Data Access Procedure:

Contact point of contact.

Data Access Constraints:

The data set has been analyzed and is available for distribution. Contact the Point Of Contact.

Data 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 Information

Distribution 1

CC ID: 260116
Download URL:



CC ID: 194820
URL Type:
Browse Graphic
Collection location map.
File Resource Format: url

Collection location map.

Technical Environment



Data Quality


multi year calibrations indicate a stable acoustic system for 38kHz, 120kHz

Completeness Report:

exploratory survey, some areas with multi year coverage.

Conceptual Consistency:

relational db, acoustic calibration, noise removal, bottom editing

Quality Control Procedures Employed:

See method in uploaded FGDC view.

Data Management

Have Resources for Management of these Data Been Identified?: No
Approximate Percentage of Budget for these Data Devoted to Data Management: Unknown
Do these Data Comply with the Data Access Directive?: No
Is Access to the Data Limited Based on an Approved Waiver?: Yes
If Distributor (Data Hosting Service) is Needed, Please Indicate: yes
Approximate Delay Between Data Collection and Dissemination: na
If Delay is Longer than Latency of Automated Processing, Indicate Under What Authority Data Access is Delayed:


Actual or Planned Long-Term Data Archive Location: To Be Determined
If To Be Determined, Unable to Archive, or No Archiving Intended, Explain:

Archival site needed for fish abundance acoustic data.

Approximate Delay Between Data Collection and Archiving: na
How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?:

IT Security and Contingency Plan for the system establishes procedures and applies to the functions,

operations, and resources necessary to recover and restore data as hosted in the Western Regional

Support Center in Seattle, Washington, following a disruption.


Lineage Statement:

View metadata record as uploaded FGDC record.

Child Items

Rubric scores updated every 15m

Rubric Score Type Title
Entity data files

Catalog Details

Catalog Item ID: 12859
GUID: gov.noaa.nmfs.inport:12859
Metadata Record Created By: Angie Greig
Metadata Record Created: 2012-08-22 14:19+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2023-05-30 18:09+0000
Metadata Record Published: 2016-05-05
Owner Org: AFSC
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Last Review Date: 2016-05-05
Metadata Review Frequency: 1 Year
Metadata Next Review Date: 2017-05-05