Purpose
This challenge aimed to produce map layers showing the extent of the fisheries impact, trawlers, on the sea-floor (gridded data), to assess whether the available marine data sets at that time* were available and appropriate to the use case, as well as to indicate gaps in the EU data collection framework.
Abstract
The Fishery Impact challenge attempted to create gridded data layers which showed the extent of fisheries impact on the sea floor using the available habitats and VMS data:
Product 1: Area where bottom habitat has been disturbed by bottom trawling
Data from a number of different sources had been integrated to provide new perspectives on fishing activities. Vessel Monitoring Systems (VMS) recorded and transmitted the position and speed of fishing vessels at intervals of two hours or less. Fishing time was then calculated from the VMS data and was combined with vessel logbook data, maps of fishing effort and intensity at different spatial and temporal scales so that it could be calculated for the various fisheries which were known to impact the seabed. The statistical software package “R” was used to extract the required information from the VMS data. The data could be re-interrogated to produce monthly maps on effort or intensity.
Product 2: Damage to sea floor to both living and non-living components
The impact of fishing on benthic habitats had previously been investigated, however a conclusive classification of potentially sensitive habitats per gear type did not exist. At that time*only qualitative estimates of fishery impact using broad-scale habitat maps were possible. Here, a sensitivity matrix using both fishing pressure and habitat sensitivity was employed to define pressure categories. A matrix-approach used to combine sensitivity and pressure was used to predict disturbance.
Team involved
Marine Institute