Second Interim Report of the Working Group on Spatial Fisheries Data (WGSFD), 10–13 June 2014, ICES Headquarters, Copenhagen, Denmark.
|Ref.||ICES CM 2014/SSGSUE:05.|
|Note||ICES WGSFD REPORT 2014 SCICOM STEERING GROUP ON SUSTAINABLE USE OF ECOSYSTEMS|
|Abstract||The Working Group on Spatial Fisheries Data (WGSFD) met at ICES Headquarters, Copenhagen, 10–13 June 2014. ICES had issued two data calls for aggregated VMS data for the years 2009–2012: one covering the OSPAR region and one covering the HELCOM region. The group evaluated the data, and used them to answer the ToRs. ICES have produced a document describing ICES Conditions for VMS data use, which all members of the group signed. The VMS data that ICES received is only to be used for ICES work and after answering the ToRs, the data are to be deleted.The submitted VMS data were aggregated to DCF métier level 6, giving more than 900 unique codes; however some countries only submitted data aggregated to level 4 gear codes. To overcome this discrepancy, it was decided to group the métiers into broader gear categories. For the OSPAR region: Bottom trawls, Dredges, Demersal seines and Beam trawls. For the HELCOM region: Gillnets, Longlines, Bottom trawls and Midwater trawls.As part of the evaluation of the data quality, the aggregated VMS effort data submitted was compared to effort data from the STECF database. These two independent datasets showed similar overall patterns, indicating that the submitted VMS dataset could be used to show the distribution of fishing effort. WGSFD produced a cleaned VMS dataset, aggregated by year and gear groupings, which other ICES EG’s can use. Caveats applying to all the VMS data products and maps in the report were listed. Based on the evaluation of the submitted data, a revised exchange format for aggregated VMS data was suggested.To answer ToR a, DCF indicators 5, 6 and 7 were computed byyear, ICES area (sub-division in the Baltic) and both by gear group and total for all gears. DCF indicator 5 relates to the total area covered by fishing activity, DCF indicator 6 has been calculated as the extent to which fishing activities are aggregated, and DCF indicator 7, the total area not impacted by fishing activities, was calculated by subtracting DCF indicator 5 fishing area from the area of the ICES area/subdivision. All the DCF indicators have been expressed both as area and proportions of the total area.In ToR a, WGSFD was also requested to contribute to ICES work on MSFD descriptor 6. The group produced a cleaned dataset, aggregated by year and gear group, which other ICES EG’s can use to relate fishing pressure to potential impact on underlying habitats. The following example outputs were produced: 1. Map of mean fishing effort in number of hours per km2. 2. Map of increase/decrease in fishing effort over the years analysed. 3. Map of number of years a c-square has been impacted, with different thresholds.For ToR b, WGSFD responded to requests from other ICES EG’s: Requests from WGBFAS and WGNSSK related to fishing effort, a request from WGMPCZM and a request from ADGVME regarding use of AIS data. For ToR c on reviewing ongoing work for analysing VMS data, WGSFD were updated on:
• the ongoing work in the BENTHIS project;
• a method developed by JNCC for estimating benthic abrasion caused by human activities;
• a nested grids method for calculating the area of the seabed impacted by fishing gear;
• the bias and variance of estimates of fishing effort from VMS data;
• production of an Atlas of Commercial Fisheries around Ireland.ToR d was a request from OSPAR to propose and apply a method to map mobile bottom contact fishing intensity and to prepare a first OSPAR-wide map of the spatial and temporal intensity of mobile bottom-contact fishing activities. The co-lead of the ICG-COBAM benthic expert group was present at the meeting to provide information both on the purpose of the data call and how the products were to be analysed. The group performed an initial evaluation of whether the data submitted served the purpose of the OSPAR request, and based on this work, WGSFD proposed a revised exchange format for future data calls for aggregated VMS data. Maps for the OSPAR region showing VMS effort by year and gear group were produced as well as a map showing the gear composition in the area and an example map applying the abrasion methodology giving maps of surface and sub-surface bottom contact.