Monitoring of seafloor litter on the Dutch continental shelf : international bottom trawl survey 2022, Dutch beam trawl survey 2021

The Marine Strategy Framework Directive (MSFD) requires EU Member States to develop programmes of measures that aim to achieve or maintain Good Environmental Status (GES) in European seas. In order to be able to evaluate the quality status of marine waters on a regular basis and the effects of the measures taken, monitoring programs for MSFD descriptors and indicators have been established by the Member States. The Dutch monitoring program for Marine Litter (Descriptor 10) includes the collection of data on the presence, abundance and distribution of macro litter on the seafloor. According to the Dutch program, the data on seafloor litter must be collected during statutory task fish surveys using a standardised Grand Ouverture Verticale (GOV) fishing net as part of the International Bottom Trawl Survey (IBTS), which is carried out yearly in the North Sea.

This report presents the seafloor litter composition, abundance and spatial distribution based upon catches of the regular fish surveys, the IBTS and the Dutch Beam Trawl Survey (BTS). Only the catches on the Dutch Continental Shelf (DCS) are used for data analysis. To assess the status of seafloor litter on the DCS, the Dutch data are supplemented with those from international partners surveying the DCS within the IBTS.