Document of dataset 2766

Dataset record

Type

Dataset

title in English

Scottish West Coast Survey for commercial fish species

Acronym

SCO-IBTS

Description in English

The Scottish West Coast Surveys use a similar ICES rectangle based sampling strategy to that used in the North Sea. Trawl stations are selected at one tow per rectangle based on a library of clear tows. There is no explicit return to the same trawling position every year, although this is generally the case. Since 1999 the potential for using a depth rather than rectangle based stratification has been under investigation. To this end, and where possible, those rectangles which display substantial internal depth variation have been sampled twice at different depths. The recent inclusion of samples collected between 200 and 500m would suggest that depth stratification should be initiated as soon as possible. The survey covers Division Via and extends into the northern part of the Irish Sea and north west of Ireland. The depth range covered has been 20 to 500m since 2000. The survey is usually carried out in March of each year. The target species are cod, haddock, whiting, saithe and herring and age frequencies are constructed for these species. All other fish species encountered are also sampled for at least length frequencies. Indices of abundance at age are calculated for all the target species and these data are used at the Northern Shelf Assessment Working Group and also made available for the Herring Assessment Working Group.

Abstract in English

The dataset includes age- and length-based catch per unit effort data for commercial fish species collected during the Scottish West Coast Survey. The Quarter 1 Scottish Groundfish survey started in 1981 and was initially intended to cover the fishing grounds on the continental shelf to the west of Scotland; in 1996 the survey area was extended to include the northern Irish Sea.

License

https://spdx.org/licenses/CC-BY-4.0.html

bibliographicCitation

Fish trawl survey: Scottish West Coast Survey for commercial fish species. ICES Database of trawl surveys (DATRAS). The International Council for the Exploration of the Sea, Copenhagen. 2010. Online source: http://ecosystemdata.ices.dk.