Development of data layers to show the fishing intensity associated with individual pipeline sections as an aid for decommissioning decision-making

Numerous pipelines have been installed in the North Sea to support offshore oil and gas extraction. Pipeline decommissioning options include full and partial removal, as well as in situ decommissioning, either with or without intervention. The choice of decommissioning strategy has social, economic and safety implications for commercial fisheries, according to the type and intensity of fishing in the vicinity. Assessing the impacts of decommissioning strategies on fisheries and mitigation options is an essential step in the decommissioning consenting process. It is important that fisheries impact assessments employ the best available data that are capable of resolving the fine-scale spatial patterns that are known to exist in pipeline-fishing overlaps. This paper describes the development of geographic information system (GIS) layers that provide high-resolution fishing intensity data for individual pipeline sections. The layers were created using fishing data extracted from the vessel monitoring system (VMS) for UK vessels operating mobile demersal gear between 2007 and 2015. The layers are freely available to download via the Scottish Government’s National Marine Plan Interactive (NMPi). The layers provide a common evidence base for industry, regulators and stakeholders to assess the impacts of different decommissioning options to commercial fisheries during the decommissioning process.