●A simple technique to "illuminate the exits" in trawl fishing nets can almost halve the numbers of unwanted catch, new research has found, potentially protecting both the environment and fishermen's livelihoods.
●Attaching LED lights to larger holes in nets, intended to allow non-target species to escape, dramatically reduced the numbers killed unnecessarily, a team from Bangor University found.
●The research, published in Journal of the Marine Biological Association of the United Kingdom, inverts an old fishing technique of shining a light on water to attract fish into a net.
●The study, conducted between June and August 2017, tested the effect of lights in reducing the number of haddock and flatfish caught in a queen scallop fishery off the Isle of Man.
●It found that while existing devices to reduce bycatch (species caught unintentionally) were effective at shallower depths of 29-40 metres, they had no effect in deeper, darker waters of 45-95 metres.
●But once LEDs were added to these "exits" in deep water, haddock bycatch was reduced by 47% and flatfish by 25%.
●Bycatch is a problem in fisheries worldwide because it inflicts further damage on often depleted non-target species, and kills mammals and seabirds that become entangled in nets.
●It can also be a huge cost to fishermen - under EU law, fishermen are required to bring ashore almost everything they catch, including fish that are not part of their quota.
●If they end up catching too much of their non-target species, their fishery can be "choked" – closed for months – to allow vulnerable stocks to recover.