Tuna Farming – Where does your sushi come from

Tuna Farming – Where does your sushi come from

The sun was beating down pretty hard. A storm from the day before had left its mark on the shallows by the hotel in Malta. The visibility had significantly deteriorated, turning a snorkel into more of a face down swim.

I used this as the perfect opportunity to investigate something that had been spoken about quite a lot by other divers in the area. The local tuna farm.

The tuna farms

It's an excursion that costs €25 each. My brother and I paid up to see what all the fuss was about. The manager of the dive shop we had been using had said terrible things about it. The company behind it had promised the local community, hotel owners and dive operators a family friendly underwater zoo.

Like some kind of open top aquarium far out at sea.

Was this an Aqua Zoo?

They told people it would be filled with numerous species, including bluefin tuna. In order to keep numbers at a diverse level, they stated that every so often they would kill an older tuna fish, process it and sell the produce.

By getting people on their side they could build the pens closer to shore.

Tuna farming

Ross Birnie

The dive manager stated that the mass of food needed to feed the tuna was spilling over the cages. This was apparently attracting larger species, including blue sharks.

He claims that Malta technically lies in great white territory. He stated the extreme number of tuna he had seen there, as well as the huge quantity of dead fish for feed, would attract them closer to shore.

Now obviously I took this with a pinch of salt, the last recorded great white attack in Maltese waters was back in 1956! That being said I was eager to explore the farms myself.

It was about 2pm on a Tuesday (the only day this particular farm will allow visitors-not to be confused with the similar 'Marine Adventure Park'). My brother and I were sitting waiting on a small jetty. The weather was perfect and the sea was becoming calmer, settling from the storm the previous day. The cool water was lapping gently against the tyres on the side of our temporary seat.

In the distance a small RIB was approaching. As it got closer, the person in control couldn't have been much older than 14, and his accomplice even younger. I gave a slightly discomforting look toward my brother as we reluctantly, and quite frankly, ungracefully clambered on to the boat.

Luckily, these two youngsters were just taking us to a larger boat for our trip. Nevertheless, the ride to it was bumpier than it needed to be. The boy was trying to impress his friend whilst shouting in Maltese.

Stay away from the middle!

Whilst boarding the next boat we were joined by several other groups. A Maltese man gave us a run down of what we were about to see. He used phrases like: “As big as a small car! Don't swim too close to the middle to avoid being sucked into the vortex created by the swirling beasts!” I took another swig of bottled water and we set off.

Plastic pollution from Tuna Farming

It was about a 25 minute journey, as we approached, you could see the huge pens. And I mean huge. There were about 12 altogether, supposedly full of various species.

Floating past our boat were dozens of plastic wrappers. I knew exactly what they were, but wanted the answer from our tour guide. “What are all these plastic wrappers floating around?” I curiously asked. “Oh that is from the food for the fish” he replied, looking slightly embarrassed.

I asked whether it was better just to cut the fish from the wrapping as oppose to merely cutting the packaging and allowing for this mass littering. He just shrugged off my question and said it was to do with lack of time.

Unimpressed I grabbed my snorkel and mask and jumped off the boat toward the pens, my brother behind. I was the first one in. It was no mean feat, having to literally hurl yourself over the cage barrier and slip in like a penguin sliding in on its belly.

What to get better at snorkeling? Here's our Full Snorkeling Guide.

It was so vast that I couldn't see the bottom of the enclosure. The water tasted awful, so oily, so much so you could actually feel the oil on your skin and in your hair. This was from the feed, fish high in fatty oils to encourage maximum growth for the tuna.

There were hundreds of dead fish, floating by our faces, unwanted food. You had to push past the various plastic bags and dodge the occasional jellyfish.

First dive down

As I took my first dive down I was truly astounded. Swimming towards me were hundreds of bluefin tuna. They were massive, some, toward the bottom, quite possibly the size of a small car. Others were unnaturally fat.

Swimming round and round in circles.

How tunas look inside a tuna farm

Ross Birnie

A handful had damaged eyes and bodies, possibly from contact with the cage.

There were no other species of fish in sight. Not quite the 'open top aquarium' we had been told about. It was a machine, a profit generator. In the near distance was a processing ship. These tuna were being caught at a younger age, avoiding laws about killing them before a certain size, because they were merely capturing them, fattening them up then killing them some years later.

They are feeding the huge demand for sushi in Japan. Weekly shipments sent fresh, generating millions every year.

Read Fish are Friends and Food.

It was quite a depressing and sobering experience. And what was so hard to take was the fact that somebody had cut a hole large enough for many of the tuna to escape through, but, perhaps due to the everyday cycle swimming in circles, they just weren't able to break away.

Not a dream of free fresh fish

Tuna fish raised in farms

Ross Birnie

As I said before: this is not the widely advertised 'Marine Adventure Park'.

I was led to believe it would be, but this was much larger and further out to sea, with a somewhat lesser degree of commercialism about it.

Don't get me wrong, it was an amazing experience to be that close to creatures of such size, majestic, streamlined and almost mechanical. But for me, it was a mere reminder that bluefin tuna should be crossing the large expanse of open ocean.

Fulfilling their natural instinct to travel.

After being stung several times by jellyfish, and our bodies coated in fish oil (which took a good four showers to remove!), we headed back to the boat. As we sat there, not saying anything, a large group of tuna was splashing around eating the food which had floated out to sea. There was a massive commotion, water splashing everywhere before they retreated back into the depths.

Free, just meters away from their imprisoned counterparts.

What do you think about Tuna farming? Would you eat Tuna now that you know it might come from a place like this? Tell us your opinion in a comment below.

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  1. ShaneMcNeil

    really? How can you tell if the fish is form a farm or free fish?
    Really don’t like the sound of this. One thing is keeping them captive, but it needs to be done properly and with the environment in mind.

  2. Grant

    WTF is this. It sound so gross! How could anyone want to dive there. Oil in the water. Is the fish eating the oil?

  3. Ross Birnie

    Yeah it’s a tough one, because there are obviously tuna farms that operate in an environmentally friendly way. Which makes it difficult to establish what kind of farm your tuna is from. To be totally honest the most sustainable option is to stick to skipjack tuna, and try to avoid Albacore, Bigeye and Bluefin. And in answer to your question Grant, the tuna do consume the oil, but it is natural oil from the fish feed, just a huge amount. RB

    • Grant

      Thanks for the answer Ross. Well that is just a bit comforting. In my mind it was cheap plat oil stuffed in the fish food and pored into the water.

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