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© Charlie Phillips/WDC

Supermarkets bycatch audit

Hundreds of thousands of dolphins, porpoises and whales die in fishing nets and ropes every year. Known as ‘bycatch’ it’s the single biggest threat they face. If you buy fish or other marine wildlife (like prawns, crabs and lobsters) from a supermarket, do you wonder where it came from or how it was caught? Is it possible to know if a dolphin died in the same net?

Map showing where whales and dolphins are caught in fishing gear in the UK
More than 1,000 dolphins, porpoises and whales die in fishing gear in UK seas every year

Many different fisheries supply the UK but 60% of sales are through 6 major UK retailers, 3 of which we have audited: Asda, Co-op, and Tesco.

We are working to persuade these six supermarkets to work with fisheries that supply them to improve practices to prevent bycatch of dolphins, porpoises, whales, seabirds, sharks and turtles

Together with Sustainable Fisheries Partnership (SFP) and Birdlife we’ve developed an audit tool to help supermarkets.

Our tool assesses the fisheries they use and tells them which of their suppliers pose the greatest bycatch risk to protected species such as dolphins.

We will also give recommendations for the actions that retailers can ask their suppliers to take, including practical actions that are sustainable for fishers, such as changing the type of net or rope used or modifying fishing practices, perhaps by moving to a different area or avoiding fishing in a particular place at certain times of the year.

Supermarket status

Supermarket engaged?
High risk fisheries

Longline fisheries for tuna in the Indian and Pacific oceans present serious risks to albatrosses, sharks, and sea turtles through the hooking of these species when they try to take bait from fishing lines or become entangled.

Gillnet fisheries for cod and haddock in the northeast Atlantic Ocean present a significant risk to seabirds and marine mammals, including porpoises, seals, and humpback whales.

American lobster pot and trap fisheries pose an entanglement risk to whales, such as the north Atlantic right whale, with their buoy lines at the surface.

Read Asda’s bycatch audit report

Alaska salmon set/drift gillnet fisheries, with significant risks to seabirds.

Icelandic cod/haddock gillnet and longline fisheries, with significant risks to seabirds and marine mammals.

Canadian (American) Lobster & UK Brown crab pot and trap fisheries, with risks to marine mammals.

Read Co-op's bycatch audit report

Tuna fisheries utilizing longlines and purse seine gears utilizing fish aggregating devices (FADs) pose a significant risk to sharks and rays, seabirds (longline), sea turtles (longline), and marine mammals (purse seine).

Alaskan salmon set/drift gillnet fisheries pose a significant risk to seabirds.

Argentine shrimp and Indonesian prawn fisheries could potentially pose a risk to sea turtles.

Icelandic cod gillnet fisheries pose a significant risk to seabirds and marine mammals.

Read Tesco's bycatch audit report

What can you do?

  • Write to your supermarket about whale and dolphin bycatch

  • If you buy fish or shellfish, think about the bycatch implications

  • Write to your parliamentarian

Practical tips

Think about the impact of the fish on your plate.

Fish are wildlife that play an important role in the marine environment as well as being fellow creatures themselves. If you decide to eat fish, by eating less and being more mindful of the fish that you buy you can make a difference, helping to send a message to the fishing and retail industry to make stronger efforts to protect whales and dolphins. To find fish with the lowest impact, look out for pole and line-caught or one-by-one fishing. Some people are making a conscious decision to stop eating fish altogether. This is a personal choice that is only open to those able to substitute fish in their diet, but it can be a powerful and positive option for some.

Organise or join a local beach clean or urban beach clean

Every piece of litter, rope or net taken off a shoreline is one less hazard floating in the sea. If you can’t remove it, at least cut any loops – as these are particularly hazardous.

Talk to your friends and family

Share your concerns. People need to know what impact we are having on the ocean and how they can help make a difference.

Timeline of campaign


Spring - Complete Tesco bycatch audit


Complete Co-operative bycatch audit


ASDA commits to improve bycatch measures in supply chain


Complete ASDA bycatch audit


WDC starts seafood supply chain auditing partnership with SFP, Birdlife

Thank you to John Ellerman Foundation for funding this project.