This article was originally published by Greenpeace International on September 4, 2015.
To the untrained eye it looks like a rogue barrel, fallen overboard from a distant ship, bobbing along in the calm Pacific Ocean.
Time and again we see odd objects floating past out here, things like mini cocktail umbrellas or polystyrene cups, and it always feels kind of strange. Even though we’re in the middle of ocean surrounded by sea for as far as the eye can see, humans have still left their mark.
But this one is more than just another piece of ocean trash. The barrel is apparently a fish aggregating device (FAD), exactly the object we’d been looking for over the past week while each of us was doing two-hour daily shifts watching the sea.
Since joining three weeks ago in Pago Pago, American Samoa, I’ve been on the Rainbow Warrior to travel around the Pacific and learn about where our tuna really comes from. This is a good start.
Before I saw one, the idea of a FAD seemed pretty elusive. I’d heard the term bandied around hundreds of times on board, but didn’t really have a clear idea of what it was. I knew that it somehow attracted a whole ecosystem of sea life, but didn’t know how. The whole thing seemed pretty mysterious.
Fish Magnets
A FAD is essentially a large object — anything from a fallen tree to a man-made structure — that floats in the sea and acts as a beacon for fish.
Our on board campaigner Karli Thomas tells me that fish are naturally attracted to floating things.
In such a vast expanse of ocean with not a lot happening on the surface, it makes sense that life would swarm to something new and interesting, to the little barnacles and mussels that begin to grow on the object.
It may also be an instinctual reaction for fish to school to something that provides a form of protection and source of food in an otherwise open sea, and after small fish gather, this in turn attracts larger fish and sharks until a mini ecosystem forms.
In simple terms, these FADs are fish magnets. And the fishing companies are taking advantage of that.
Targeting Tuna
Tuna companies realized fishing would be easier for them if they created custom-made fish magnets and left them out at sea for several months, to give them time to attract an ecosystem of fish. All they needed to do then was turn up with their nets and catch them all.
Although these companies mainly target tuna, you can imagine how many other sea creatures — including sharks and sea turtles, get caught up in this game — becoming just another bycatch statistic.
The fish magnets themselves also often get discarded or lost at sea, turning into deadly ocean trash that can tangle on coral reefs or trap turtles and other animals. We’ve heard stories from friends working in the Indian Ocean about the sheer scale of the problem they are facing.
There are two main kinds of fish magnets that fishing fleets use. The first is left to float with the currents, more or less following the migration path of the tuna. This one is kitted out with a radio beacon so fishing boats can keep track of it and find it again when it’s time to fish.
The second is the kind we’ve come across. It doesn’t need a radio beacon because it is anchored to the bottom of the sea. As unbelievable as it sounds, our barrel-like fish magnet has an anchor that is more than four kilometers deep.
What We Found
As we approach, many of the fish that have been living on the barrel make a beeline for our boat, obviously a bigger, shinier more interesting object for them. It’s fascinating to watch — there are so many fish, all different colors and species.
The Rainbow Warrior videographer, Adams Wood, and photographer, Paul Hilton, get into their wet suits and snorkeling gear and swim out to the fish magnet.
Like me, it’s the first time that Adams has seen one.
“It’s like a fish circus down there,” he says. “There are even a few juvenile sharks living around this thing. I would say it’s an amazing little marine reserve, but knowing the purpose of it makes it bittersweet. Knowing all the life there has been lured in and is destined to be killed is sad.”
Photographer Paul is the fish expert. Among the species he sees around the barrel are trigger fish, silky sharks, rainbow runners, bat fish and mahi mahi.
As he goes through the list I’m reminded of a quote by Charles Clover, the author of “The End of The Line.”
On the use of fish magnets, he says: “Killed alongside the skipjack tuna that finds itself in your tin is almost the entire cast list of Finding Nemo.”
Plummeting Tuna Populations
It’s the purse seine boats that drop nets of up to 60 soccer fields in area, and three Ferris wheels in depth, that are using fish magnets as a way to guarantee a decent catch.
And although they are banned from fishing around them for five months out of the year, the boats don’t actually have to remove their magnets from the water during this period.
So while the purpose of the ban is to give plummeting tuna stocks a chance to bounce back, what happens in reality is the magnets have more time to attract an even larger accumulation of fish, all of which get scooped up and killed the moment the ban ends.
And the most worrying part of all this is that fish magnets have a knack of being particularly attractive for juvenile bigeye tuna, hitting that already under pressure population where it really hurts.
What’s the Solution?
The only way to make fisheries fair and ensure that we don’t completely strip our oceans of tuna is to ban purse seiners’ use of these fish magnets altogether.
It’s already hard enough for the fish as it is. They have to cope with the huge industrial fishing fleets that roam the ocean, pulling up thousands of tonnes of tuna a day.
With the number of purse seine boats reaching all-time highs, it’s simply madness to allow those vessels to ramp up their catches even further. Certainly not if we want to have any sort of sustainable tuna industry in the future.