Safety nets: Can smarter fishing gear protect marine life and keep fishers afloat?

In the French part of the Bay of Biscay, one of Europe’s richest fishing grounds, thousands of dolphins die each year after becoming accidentally entangled in fishing nets.

On average, around a thousand dolphins are found stranded on beaches every winter. But according to the PELAGIS observatory’s analyses reported by Bastien Mérigot, coordinator of the DolphinFree project, the total mortality is estimated to be much higher — with 4,500 to 8,500 dolphins caught in fishing gear every year. Many dolphins that suffocate in nets never make it to the shore — they sink unseen, leaving researchers to grapple with incomplete data on the full extent of the problem.

These losses not only undermine marine ecosystems — they also disrupt the livelihoods of fishers who depend on these waters. For the second winter in a row, authorities have imposed a month-long closure of fisheries to reduce the risks to dolphins. In the meantime, several European research projects are looking for innovative technological solutions that can protect marine life without halting fishing altogether.

To address the Bay of Biscay crisis, the DolphinFree project, funded by the European Union and the fishing sector association “France Filière Pêche”, is pioneering a new approach: an acoustic beacon for fishing nets, designed to integrate with dolphins’ natural sonar-based communication. This device emits signals that mimic the echo patterns dolphins rely on to navigate their surroundings. By creating an acoustic image of danger — a recorded echo of a fishing net with a dead entangled dolphin — the beacon prompts dolphins to avoid the area.

Initial tests conducted by the scientists show promising results. Dolphins react to the beacon’s signal by steering clear of