Dolly ropes (DR) are used in beamtrawling and other types of fishing to protect the nets from being ripped by the sea bottom. They constitute an important source of plastic pollution in the regions where this type of fishing prevails. The aim of this project is to assess spatially, quantitatively and qualitatively the extent of the pollution caused by this gear. For this, a hydrodynamic model will be created containing the following information: • Hydrodynamic properties of the north sea. An already existing model will be used for this part. • Spacial distribution of the free floating sampled DR. The coordinates of each DR sampled by Bastian Huwer will be inputted in the model to represent the actual spatial distribution of the DR. Additionally and if possible, some of the sampled DR will be analyzed with electron microscopy to allow qualitative dating of the object. The intensity of fishing using this gear will be spatially estimated to be inserted into the model as a source of DR pollution. • Physical properties of the DR. The DR collected were weighed and measured. A laboratory experiment will be conducted to assess potential vertical distribution of the objects and the plastic composition and its properties will be assessed. • Interaction with biosphere will be implemented into the model based on available literature.