Extraction of fish - Herring extraction (landings) (HOLAS 2)
Short description
The extraction of herring data set is based on: 1. http://metadata.helcom.fi/geonetwork/srv/eng/catalog.search#/metadata/a3b67a55-7c1e-469e-b692-58c4e7b79279 for years 2011-2016 reported per ICES statistical rectangles (tonnes / ICES rectangle). Landing values were redistributed within each ICES rectangle by the c-square fishing effort data provided by ICES (all gears, 2011-2013). Tonnes / km² was calculated and the results were converted to 1 km x 1 km grid cells. The layer was log-transformed and normalised to produce the final pressure layer on extraction of herring. Please see "lineage" section below for further details on attributes, data source, data processing, etc.
Point of contact
HELCOM Secretariat
data@helcom.fi
Spatial extent
['7.530495', '33.935498', '52.515454', '66.475422']
Type
dataset
Metadata information
Identifier
Keywords
Bio-geographical regions ; GEMET - INSPIRE themes, version 1.0 ;

environmental impact of fishing ; fishery ; GEMET ;

MADS ; HOLAS2 ;

Resource provider(s)
HELCOM Secretariat
data@helcom.fi

Lineage
Data source: The commercial landings data has been downloaded from EU Joint Research Centre’s data collection framework for fisheries data. Available here. Russian data extracted from ICES annual reports. Data from Russia was only available at the scale of ICES sub-divisions and was equally redistributed to all ICES rectangles within that sub-division. Data processing: Average values (2011-2016) per square kilometre (tonnes/km²) was calculated for the data set. Commercial landing values were redistributed within each ICES rectangle by the c-square fishing effort data provided to HELCOM by ICES (all gears, 2011-2013). Effort values were missing from Russia and sub basin average values given. The maximum value of tonnes per square kilometre from the original ICES rectangles was used to scale the maximum value for commercial catches. The layer was log-transformed and normalised to produce the final pressure layer on extraction of herring. Data quality: The commercial landings data is obtained from one source, but there may be gaps or mistakes in the reporting of the landings data. The effort data used to redistribute landing values was only available for the years 2011-2013. This lowers the quality of data to some extent, however the large scale pattern of fishing can be considered to be relatively stable. Attribute information: Final normalised pressure value (0-1) Spatial coverage: Entire Baltic Sea. Spatial resolution: Original data reported in ICES statistical rectangles (commercial landings) and ICES c-squares (redistribution). Here 1 km x 1 km grid.