Working Group on Electrical Trawling (WGELECTRA)

The Working Group on Electrical Trawling (WGELECTRA), works on improving knowledge of the effects of electrical or pulse fishing on the marine environment. In this report the group pro-vide details of ongoing work including preliminary results, upcoming research projects, and possibilities for international collaboration and scientific publications. A living document, over-viewing the current published scientific knowledge on pulse trawling, was updated and attached as annex.

Highlights of ongoing research included presentations about laboratory and field experiments on the effects of electrical stimulation on fish, benthic invertebrates and biogeochemical pro-cesses. Results were presented of a monitoring project in which pulse trawl skippers record the catch and effort by tow. This information provides insight in the dynamics of pulse trawlers exploiting local aggregations of sole and can shed light on the effects of pulse fishing on local aggregations of fish and on possible competitive interactions between vessels. Further, pulse stimulation can also be used to increase selectivity in the net instead of a capture technique. This was shown by the studies of the Instituut Voor Landbouw-, Visserij-, en Voedingsonderzoek (ILVO) showing that a 200 mm benthos release panel equipped with an electrical stimulus (eBRP) has the potential to release up to 75% of the benthos and debris immediately after capture with-out significant losses of marketable Dover sole and other species. Other work focused on pulse trawling targeting brown shrimp. The preliminary results of an elaborate Dutch study including active pulse trawlers targeting shrimp confirmed that a pulse trawl with a straight bobbin rope and 12 bobbins can obtain similar or slightly higher catches of marketable shrimp, while showing drastic reductions in the bycatch of other invertebrates and fish. Finally, the group discussed a number of upcoming research projects including the study of the changes in catch rate of various fisheries in relation to emergence of pulse fishing.