Data report : 2012 Aleutian Islands bottom trawl survey. : 2012 Aleutian Islands bottom trawl survey

The 2012 biennial bottom trawl survey of the Aleutian Islands region was conducted from 4 June through 14 August by the Resource Assessment and Conservation Engineering (RACE) Division of the Alaska Fisheries Science Center (AFSC), National Marine Fisheries Service (NMFS), Seattle, Washington, marki...

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Bibliographic Details
Main Authors: Raring, Nate W., Laman, Edward A., Von Szalay, Paul G. Paul Gunnar, Rooper, Christopher N., Martin, Michael Hall
Format: Text
Language:English
Published: U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Alaska Fisheries Science Center 2016
Subjects:
Online Access:https://dx.doi.org/10.7289/v5/tm-afsc-332
https://repository.library.noaa.gov/view/noaa/12211
Description
Summary:The 2012 biennial bottom trawl survey of the Aleutian Islands region was conducted from 4 June through 14 August by the Resource Assessment and Conservation Engineering (RACE) Division of the Alaska Fisheries Science Center (AFSC), National Marine Fisheries Service (NMFS), Seattle, Washington, marking the twelfth comprehensive NMFS bottom trawl survey of this area since 1980. The surveys conducted prior to 1991 were cooperative efforts involving U.S. and Japanese scientists and vessels. From 1991 to 2000 the surveys were planned and conducted on a triennial basis by NMFS, employing chartered U.S. fishing vessels. Biennial surveys began in 2000. The 2008 survey was cancelled. The primary focus of these surveys is to continue a standardized (Stauffer 2004) time series of data to assess, describe, and monitor the distribution, abundance, and biological condition of Aleutian groundfish and invertebrate stocks. This report presents 2012 survey results for the principal fish species in areas corresponding to subdistricts of each of three North Pacific Fishery Management Council (NPFMC) regulatory areas: Eastern, Central, and Western Aleutians as well as a fourth survey area located in the southern Bering Sea. These areas are further described in the “Survey Design” section of this document. No detailed comparisons to previous surveys are made in this report, however, most time-series of principal groundfish and invertebrate species are available through the AFSC Resource Ecology and Ecosystem Modeling website1 . Specific survey objectives were to: 1) define the distribution and relative abundance of the principal groundfish and important invertebrate species that inhabit the Aleutian region; 2) obtain data from which to estimate the abundance of principal groundfish species; 3) collect data to define biological parameters including age, growth rates, length-weight relationships, feeding habits, and size and sex compositions; 4) collect accurate net mensuration data describing the fishing effort of standard research trawls used by all of the vessels during the survey; 5) conduct special collections as requested by other researchers or research groups. Special collections were made for projects addressing genetics of blackspotted and rougheye rockfishes, different species of corals and creating a genetic database for several prey species for use in trophic analysis. Additional projects included collection of octopus sex and weight data, snailfish and lumpsucker voucher specimens, sponge taxonomy, monitoring the presence of snailfish eggs in king crab as well as bigmouth sculpin eggs in sponge, ambient light levels during fishing operations; acoustic profiling, and recorded observations of short-tailed albatross.