Fishing activity near Petrogas offshore pipelines, 2022

Numerous pipelines lie on the North Sea seabed to link oil or gas offshore drilling units, platforms and processing stations on land. Although pipeline tubes are coated and covered with protective layers, the pipelines risk being damaged through human-induced hazards like anchor dropping and fishing activity with bottom trawls. Petrogas E&P Netherlands B.V. works towards integrated risk assessment of pipelines. Spatial maps of fishing activity contribute to this risk assessment. Therefore, WMR was tasked with quantifying the amount of fishing activity in the vicinity of Petrogas E&P Netherlands B.V. pipelines. Fishing activity was quantified at a spatial scale of approximate 3800 m2 blocks (68m by 56m) using fishing Vessel Monitoring System (VMS) data from the year 2022. Fishing activity was quantified in both a fishing intensity factor (number of times a full grid cell is trawled) and the total fishing effort for each grid cell, expressed in minutes. The results in this study show that larger vessels as well as smaller vessels do operate a fishing in the vicinity of the pipelines located closer to shore. In the northern part of the EEZ, fishing intensity is low for larger vessels and negligible for smaller vessels and shrimp trawlers. The highest fishing intensity is recorded close to the IJmuiden harbour due to shrimp trawling activity and amounts to an estimated 3- 4 times trawling intensity around the pipelines. It is however realised with gears substantially lighter than traditional beam trawls. This fishing intensity is below the range of 5-10 times a year estimated in the most intensively fished areas of the North Sea. The indicators calculated in this study, reflecting number of potential interactions (fishing effort) of trawling vessels with the pipelines and the potential severity of these interactions (fishing intensity), may contribute to the risk assessment. It should be noted, however, that owing to seasonal changes in fish distribution and yearly changes in fishing gear characteristics, these maps do not provide an accurate base for the prediction of future fishing impact