- Princes has switched from Atlantic mackerel to Chilean jack mackerel in some of its tinned products.
- The substitute is cheaper and contains less omega-3 than the mackerel many British consumers expect.
- The switch comes as scientists and conservationists warn that Atlantic mackerel stocks are under serious pressure.
A tin labelled mackerel may no longer contain the fish British shoppers traditionally associate with the name.
Princes, a major supplier of tinned fish to UK supermarkets, has switched to Chilean jack mackerel, a completely different species from Atlantic mackerel. The fish is also known as Peruvian jack mackerel and comes from the waters of South America.
The change is already reaching major supermarket shelves. Tesco and Sainsbury’s sell Princes tinned fish, while other retailers have been changing their mackerel sourcing.
For shoppers, the difference is more than a technical detail about species. Chilean jack mackerel has around 100 fewer calories per 100g and roughly half the omega-3 of Atlantic mackerel. Some consumers have also complained about larger bones and a metallic smell.
Yet the price difference may not be obvious at the checkout.
Industry figures suggest wholesale Chilean jack mackerel costs roughly one-third as much as Atlantic mackerel, while some retailers are selling products containing the cheaper fish for a similar price.
That creates an uncomfortable question for consumers: if the fish has changed and the ingredient is cheaper, should shoppers still be paying the same?
Sue Davies, head of food policy at Which?, said the change was particularly concerning because tinned fish is an important source of nutrients for many households.
“It's a real concern when manufacturers quietly downgrade everyday staples like these, as shoppers can end up paying the same price for a product that delivers significantly less nutritional value.
“While manufacturers face genuine supply chain pressures and sustainability challenges, they have a responsibility to shoppers to be completely upfront when they change a product's recipe. ‘Skimpflation’ – quietly changing ingredients to cut costs – has become increasingly common, but it can feel particularly sneaky as shoppers may not realise a product has changed until they get it home and eat it.”
Why is Britain running short of mackerel?
There is, however, a bigger reason behind the switch than cost.
Atlantic mackerel stocks in the northeast Atlantic have come under increasing pressure. According to the International Council for the Exploration of the Sea, mackerel stocks have fallen by around three-quarters over the past decade.
Scientists warned last year that fishing for the species should be reduced by more than 70 per cent to help prevent the collapse of fish stocks.
The problem has been made worse by years of disagreements between countries over how much mackerel can be caught. Since 2010, quotas have been set an average 39 per cent higher than scientific advice.
The resulting dispute, often described as the ‘mackerel wars’, has involved the UK, Norway, the EU, Russia, Iceland, Greenland and the Faroe Islands.
Retailers have increasingly responded by reviewing or changing their sourcing. Waitrose, for example, cited overfishing concerns when it announced in April that canned mackerel products would be phased out as existing stocks were sold.
Lidl has also been transitioning away from northeast Atlantic mackerel in some products. The supermarket said it was “committed to sourcing fish and seafood from responsibly managed fisheries”.
It added: “Before our next purchasing window for smoked mackerel, we will review if northeast Atlantic mackerel continues to comply with our sourcing policies and scientific advice.”
The problem is that replacing depleted Atlantic mackerel with fish caught thousands of miles away creates its own contradiction.
“It is a great pity that we will eat imported fish from a long way away instead of locally caught fish,” Stewart Harper, former managing director of North Atlantic Fishing Company, reportedly said.
“The consumers will be suffering because pure mackerel is a much better species to eat than jack mackerel.”
For supermarkets, the switch is therefore a balancing act between protecting fish stocks, maintaining supply and keeping products affordable.
For shoppers, the lesson is simpler: the word ‘mackerel’ on the shelf does not necessarily mean the same fish it used to. As retailers respond to a growing sustainability problem, consumers may need to look more closely at the species listed on the tin, particularly when the price has not changed with the fish inside.
