View from the Inside: Sustainable Tuna

Tuna is one of the most consumed fish in the world. It’s so popular, we’re even keen for our favourite pets to get in on the action: one of the most common Google searches for it is “Can dogs eat tinned tuna?” (a quick scan of the answers suggests this is probably not a great idea).

We also want to know “How much protein is in tuna?” (upwards of 20g per 100g) and “How long tinned tuna lasts in the fridge?” (it would be irresponsible to answer that one – and depends on how you’re storing it and your fridge temperature). 

Do you know what is not a common search? – “Where can I find sustainable tuna?” – either we don’t think to ask or we don’t want to know the answer to that…

If that’s you, you can stop reading now. But, if you do want to know how to eat tuna sustainably (yes, it is possible!), then Charles Redfern, founder of Fish4Ever, probably the UK’s most sustainable tuna brand, answers every question you’ve ever had about tuna – and those you never even thought to ask…

Fish4Ever | Tuna chunks
Sustainable tuna: Fish4Ever

LF: Why is tuna so popular?

Charles Redfern: A taste for sushi, tuna steaks and cans (of tuna) have all increased the demand for tuna. 

Supply started exploding in the 1970s, when a new fishing method, Purse Seine fishing (more on this later), meant fishers could massively increase their catch. 

So, we have gone from fishing 1.5 million tonnes of tuna a year to a whopping five million tonnes, today. 

Are there different types of tuna?

We eat five main types of tuna:

  • Bluefin: Premium fish used for sushi and steaks in high-end restaurants. 
  • Big-eye: Most commonly found in sushi chains.
  • Yellowfin: Most likely found in supermarket sushi steaks, also in cans.
  • Albacore or white tuna: Used for steaks (slightly drier than yellowfin) and in cans.
  • Skipjack: Most commonly used in cans, but also eaten fresh in local markets.
Fish4Ever | the different types of tuna

What are the biggest sustainability issues when it comes to tuna?

The biggest issue with tuna fishing is the method of catch. The most dominant fishing method is Purse Seine fishing. 

Purse Seine fishing is a large net that pulls together at the bottom (like a drawstring bag, if the bag were the size of a football pitch). It is used to capture schools of fish swimming together near the surface of the ocean – and an unfathomable amount of other marine life gets caught up in it, too. 

One issue is that as tuna get older, they swim deeper and migrate further (they can swim from the Gulf of Mexico to Europe and back again). So, Purse Seine fishing is capturing younger fish in huge quantities. This is catastrophic because it’s not giving them the chance to mature and reproduce (and keep stock levels high). 

Another issue is that Purse Seine fishing doesn’t just happen when fishing vessels are coming across schools of fish. They use Fish Aggregating Devices (FADs) – floating objects that drift on the sea with bits dangling below the surface to attract sea life. Each boat monitors multiple FADS at the same time. A satellite transmitter on the FAD tells the Purse Seine boat when there is a lot of fish. This is then verified by an on-board helicopter. If big volumes of tuna are located, the boat sets off to that FAD.

Video highlighting the difference between Purse Seine Fishing with Pole and Line fishing

The problem is, the most prolific species of tuna – juvenile yellowfin and big eye tuna – are scooped up in vast numbers before they’ve had the chance to reproduce (which threatens the species as a whole). Many other marine creatures, including sharks, turtles, and cetaceans (whales, dolphins, and porpoises) are caught, too.

Shockingly, the MSC classes Purse Seine fishing as sustainable tuna and regards this bycatch as acceptable. For example, the largest certified Purse Seine fishery in the Western Pacific recorded 30 species caught as by-catch in its official report.

The industry always talks about “managing total tuna stocks” – but this isn’t the issue. The issue is the way tuna are being hoovered up. If we had more sustainable fishing methods, we would have more sustainable tuna.

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What are the other methods of catch for tuna?

Long lines, which can run for several miles, are the next most popular way to catch tuna. These are exactly as they sound, long lines with baited hooks. They sit on the surface or go deeper into the ocean. At their worse, they have high levels of bycatch, more than 20%, which can include endangered sharks, turtles, albatross and other birds. 

Can tuna be farmed, like salmon?

Big corporations are still trying to master tuna farms, so currently tuna is either wild or ‘ranched’.

Bluefin is ranched north of Libya and south of Malta, which means young bluefin are captured and stuck in pens where they are fattened until they reach a sellable weight. 

You need to feed 20kg of wild fish per 1kg of bluefin, so it’s quite an inefficient feed-conversion ratio, which isn’t sustainable. 

There’s also ethical considerations around the conditions the tuna are caged in, as well as caging a fish that swims so far. It could have huge consequences on the marine ecosystem. 

There’s also alleged Mafia links to ranching. But, that’s another story…

Fish4Ever | Pole and Line caught tuna
Fish4Ever | Pole and Line caught tuna

What’s the difference with Fish4Ever tuna?

At Fish4Ever, we use the artisan Pole and Line method – with fishers catching tuna one-by-one, using a hook attached to a line and pole in Portugal and the Maldives. 

It’s important because it has near-zero by-catch. In the Azores (Portugal) we have the longest-running scientific tuna programme in the world. It was established in 1980 to observe and monitor the fishery. The by-catch level is less than 0.4% and there is zero harming of cetaceans.

Fish4Ever | Pole and Line fishing
Fish4Ever | Pole and Line fishing

Confusingly, FADs can also be used with Pole and Line fishing. They are not used in the Azores, where most of our tuna is sourced. But, FADs are used at the biggest Pole and Line tuna fishery in the Maldives, where we’ve started working with an established, certified Fairtrade project.

These are anchored FADs so there is far less risk of them being lost at sea and, of course, because the fish are caught one-by-one, the FADs do not have the same negative bycatch issues.

As well as being more ecologically sustainable, the standout difference with Pole and Line fishing is that it is also more socially sustainable. The fisheries are locally-managed and controlled. Access to the fishery is equitably distributed and so the wider community benefits economically.  In terms of pay and conditions, our Pole and Line fisheries are exemplary with living wages, health and safety, and human rights all respected.

Are there human rights issues with industrial tuna fishing?

Industrial tuna fishing is a system based on pools of low-paid labour. Fishers work far from their homes, often living on boats for whole seasons. The owners are often large corporations in tax havens, focused on profits and trying to get away with as little social- and ecological- responsibility as possible.  Sadly, it’s not surprising that scandals of human rights abuse, slavery at sea, and illegal shark finning appear on a routine basis.

Is tuna fishing linked to the oceans’ plastics issue?

Lost fishing gear accounts for around 10% of ocean plastics. But, lost nets, for example, will continue to entangle marine life and so its impact is even more significant. We’ve all seen pictures of a trapped turtle or sea bird. It’s extraordinary that this type of negative impact is so poorly regulated. It’s a clear example of how our current food and economic systems allow for public damage in the name of private profits.

Fishing nets

Last year, we became the world’s first ‘plastic neutral’ fishery. In fact, we’re plastic positive. 

Pole and Line plastic losses are intrinsically tiny, but we sponsored a pilot plastic retrieval project and over three months our fishers retrieved 875 times more ghost gear in weight than they lost annually in their own fishing operations.

This program has now been funded for another three years.  Our hope is that this will lead to the Ministry of Fisheries establishing a permanent retrieval program.  

Why doesn’t Fish4Ever have the MSC blue-label on cans of its sustainable tuna?

The MSC standard generally is shockingly low. People are being led to believe the MSC-blue tick guarantees sustainable fishing when it’s simply not true.

On the one hand, the MSC claims to be of the highest sustainable standards possible, and on the other hand, it talks about the long journey towards sustainability. This second part is much more accurate.

Currently, the MCS is mid-way through an arduous review process. It essentially confirms that the system is too lax with too many holes and too much leeway for the auditors to make their own interpretation of the rules. For example, when it comes to tuna, almost 90% of MSC certified fish comes from industrial Purse Seiners. There’s nothing sustainable about this.

Many independent experts range from quietly exasperated to highly critical. Even the WWF, who helped to set MSC up in 1996, have finally come out publicly with their concerns about it.

We would probably sell more cans if we did have it, but ideologically, it’s a misrepresentation and I can’t support that. 

Fish4Ever | Tuna chunks

So, is canned tuna healthy for you? 

Tuna is well known as a good-quality, low-fat protein.

But, it does vary according to how the tuna is caught and processed. 

The Japanese talk about “yake-niku” which is colloquially known as “burnt tuna”. 

Burnt tuna is a condition that can develop during the stress of capture. Essentially, the stress reduces oxygen to the muscle and causes other metabolic changes, too – leading to a sour/burnt tuna taste.  

Another factor that impacts the quality is that most canned tuna available is de-boned and de-skinned in one place, then frozen and sold to a canning company, which will then have to unfreeze it a second time, before putting the tuna in a can.  

Together, these two issues essentially lead to a poorer quality product – and you can taste it in the tuna.  The Fish4Ever difference is that we only work directly from whole fish, fished one-by-one and processed in one go. 

From a sustainable perspective, should we be eating tuna at all?

I think it’s the same for any food: if you care about the issues, you should try to support the best practice.

In terms of carbon footprint, a diet with eggs and fish is almost the same as a vegan diet and much better than a vegetarian diet, according to some calculations.

Fish4Ever | Sustainably fished tinned tuna
Photo by Alesia Kozik from Pexels

What are the best certifications to look out for?

I think the best certifications are Organic, Naturland, Fairtrade USA (there is no UK/EU Fairtrade fish standard…). Although, note that wild fish itself can’t be organic. At Fish4Ever, we use wild fish with organic oils or sauces.  

Also, watch this space. We’ve been working on an alternative to the MSC, which will hopefully be launching soon…  

Finally, where can we find Fish4Ever?

It’s stocked in Ocado, Abel & Cole, Wholefoods, and Planet Organic. It’s also in many independent farm shops, natural food stores and delis. Or, you can buy it directly from their website:

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Here’s our top two favourite brands for buying genuinely sustainable fish:

Sole of Discretion log | sustainable seafood

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Fish4Ever | sustainable tinned fish


The UK’s most sustainable tinned tuna.

About the author

Charles Redfern

Charles Redfern


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