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Top ten sustainable fish swaps

The Sustainable Fish City: Top Ten Swaps have been devised with advice from expert organisations that contribute to the Sustainable Fish City working party (see the About page for more information). The top swaps are now also available as pdf downloads:

We have also included tips on where to buy more sustainable alternatives, from top supermarkets that score consistently highly in the Marine Conservation Society sustainable fish supermarket survey. Click on the name of a fish below to find out more


Please feel free to use this information elsewhere, but if you do so, please let us know ( and please include a link to Sustainable Fish City:



Why swap?

There are lots of different species of tuna, a few of which are critically endangered and some of which are caught in ways that damage other marine life.

Top swaps for tuna

Try Marine Stewardship Council (MSC) certified albacore tuna – hand-caught in the Pacific Ocean. Albacore has very light, firm and delicately flavoured meat, and is available canned and in jars. Most canned tuna is skipjack, the most resilient species of tuna, with all stocks currently healthy – choose pole and line, handline or troll caught.



Why swap?

Salmon are sometimes farmed very intensively, leading to serious environmental problems. Also, farmed salmon have to be fed large quantities of feed made of wild-caught fish, and the fish used to make the feed can have conservation issues of its own.

Top swaps for salmon

Why not try MSC certified Alaskan wild salmon. It's much leaner than farmed salmon, so be careful not to overcook it. Alternatively, look out for certified organic farmed salmon or RSPCA assured farmed salmon.


Why swap?

Our love of this chip-shop favourite has led some haddock stocks to be over-fished. And haddock often swim with cod (see below), meaning that haddock fisheries may catch both fish. 

Top swaps

Look out for MSC certified haddock from Scotland or Norway, or try a different firm, white fish such as coley (often sold as saithe), which has an undeserved reputation as something you feed to the cat but, when spanking fresh, is delicious.



Why swap?

Some stocks of cod are seriously overfished.

Top swaps for cod

Try UK-landed pollack, coley, hake or whiting, or MSC certified Alaskan pollock. MSC certified cod is available from the Arctic, Atlantic & Pacific. If only cod will do, go for MSC certified cod from the Arctic, Atlantic & Pacific oceans.



Why swap?

King or tiger prawns are usually farmed in the tropics, often very intensively and in ways which can seriously damage local communities and the environment. The fish used as feed has been linked to slavery.

Top swaps for prawns

Choose organic tiger prawns, or for a more local option, go for Scottish langoustines (also known as Dublin Bay prawns or scampi). Or look out for the smaller MSC-certified cold-water prawns from Canada. Like prawns, crab is as good with strong flavours like chilli as it is plain with lemon and mayonnaise.



Why swap?

Left to their own devices, plaice can live for 50 years or more. They grow and reproduce very slowly, making them vulnerable to overfishing. Many UK populations are in serious decline

Top swaps for plaice

More sustainable flatfish choices include flounder, dab or lemon sole (ask for fish caught by otter trawl or seine net). Or go for MSC certified plaice, or MSC certified Dover sole.


Why swap?

Big, slow-growing 'game' fish like swordfish are particularly vulnerable to over-fishing.

Top swaps for swordfish

Nothing similar fits the sustainability bill, but jig-caught squid, herring and sardines stands up to strong flavours and is delicious grilled or on the barbeque. 

Where you can buy top swaps for swordfish

  • A good local fishmonger may stock jig-caught squid.

Sea bass

Why swap?

Scientists recommend reducing fishing UK stocks by 80%. Fish feed is a concern for farmed seabass.

Top swaps for sea bass

Organically farmed sea bass from Wales, or line-caught black bream, porgy or seabream. ASC-Certified pangasius (often sold as ‘basa’) is a good alternative.



Why swap?

Sadly, the once “common” skate is now critically endangered, and several other species of skates and rays are overfished.

Top swaps

Try an under-loved UK-landed species such as dab, pouting or sole



Why swap?

Halibut is a Slow-growing, long-lived species. Atlantic stocks are considered endangered

Top swaps

MSC certified Pacific halibut, Scottish farmed halibut or organic gilthead bream.


Top Tips for Top Ten Swaps

Look out for the Marine
Stewardship Council (MSC)
eco-label, showing that the seafood
is from a certified sustainable source.


For farmed fish, Freedom
Food and Organic certified
are a good option.



Top tips for scallops and nephrops

There have been particular environmental concerns associated with two UK species in recent years; dredged scallops and trawled Nephrops (sold as langoustine and scampi) which can impact the seabed in severe ways.

Find out more



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