A new method using AIS data to obtain independent compliance data to determine mitigation use at sea

Seabird mitigation measures use is a requirement for all pelagic longline vessels south of 25oS in the Atlantic and Indian Ocean, and south of 30oS in the Pacific. Monitoring the implementation of these measures is difficult due to low levels of observer coverage and the remote environment operations are conducted. Recent advances in technology provide opportunities for improved compliance monitoring at minimal cost. Here we describe a novel method for monitoring night setting compliance using Global Fishing Watch’s AIS data. We assessed more than ~61,000 sets by over 300 vessels for compliance with night setting regulations using a convolutional neural network. Results indicate that in areas where seabird mitigation measures are required a maximum of ~15% of sets have less than two hours overlap with daylight, and the percentage of sets fully compliant with night setting could be much lower (<5%). In future, technology could be used for monitoring night-setting compliance at a broad scale by Member States, RFMOs and the wider public.