You know that colourful tin of tuna you drop into your supermarket basket every week? Ever wonder what’s in it? Probably not; in a matter of decades, tuna has gone from being exotic mystery to an almost generic foodstuff, as ubiquitous as bread and milk – there’s even one brand of canned tuna called “chicken of the sea”.  No disrespect to chickens, but the many species of formidable, predatory tuna that charge around our oceans in large schools are in a different league altogether.

But back to the tinned variety; Greenpeace recently commissioned the first ever independent, public genetic tests into tinned tuna, to find out what was really going on inside 50 brands of tinned tuna. Analysis of products from 12 countries, including the US, Canada, Australia, and several European countries, turned up some pretty dodgy things inside some of them.

Inside some tins (brands Calvo, Campos in Spain), two different species of tuna were found, which is illegal in several jurisdictions, including in the EU, while in others (for example Clover Leaf in Canada and Nostromo [owned by Calvo] in Italy), tins from different batches were found to have different species inside separate tins.

While this apparently sloppy behaviour should set alarm bells ringing from a consumer point of view, there’s actually even more to be concerned about; the tinned tuna industry, through what appears to be lazy disregard for both its customers and future tuna availability, is forcing consumers and retailers into involvement in a trail of destruction.

>> TAKE ACTION: Demand marine reserves to protect species under pressure.

It starts with a fad. That’s FAD, or a fish aggregation device– an elaborate name for an object placed in the water, which attracts lots of fish. FADs allow the fishing industry to catch a lot of tuna at the same time, but since different species are all attracted, including young fish it also causes a lot of bycatch.

Turtles, sharks, and various species of tuna, including juveniles of species under pressure like yellowfin tuna or bigeye tuna are caught in the same nets. This is not only killing hundreds of thousands of sharks, which are either drowning in the nets or dying an agonizing death once they have had their fins cut off and are thrown back into the sea, but it is also killing turtles and non-target fish species.

Now, we’re not saying there’s turtle or shark in your tuna tin, at least not literally. But when the juvenile tuna are sent ashore for processing and frozen, identification and sorting is apparently very difficult, resulting in species being mixed in the tinning process. We say apparently, as it may just be a case of it being financially uninteresting for the tuna industry to separate the species.

Whatever the reason, the problem keeps coming back to FADs. By using these fish-attractors in tandem with purse seine nets, the tuna industry is destroying its own future and pushing towards the collapse of tuna stocks.  By catching small, young fish, it’s ensuring that there will be fewer large tuna in the future. That’s bad news for your tuna salad, bad news for the fishing industry, and dismal news for the “chicken of the sea”.

Greenpeace is calling for a ban on FADs in purse seining – we want them banned for using tuna fishing throughout our oceans. Fishing with seine nets only would help minimise the bycatch of other animals, as well as drastically reduce the amount of juvenile tuna ending up in tins.

To help support such a ban we need to take action in the supermarket. Consumers don’t want dodgy tuna, and neither do retailers.  Every industry fears the wrath of consumer opinion; and we can use this to persuade the tuna industry to clean up its act, and to stop forcing dodgy tuna down our throats.

Photo: Fish school and a shark congregate around a fish aggregation device.  © Paul Hilton / Greenpeace

Note from AZTI-Tecnalia, who performed the tests for Greenpeace: Analytical results performed by AZTI-Tecnalia under its patented method for discrimination of Thunuus obesus and Thunnus albacares. AZTI has not participated on the sample collection and the design of the experiment and is not responsible for the use of the results delivered, or any information derived from its analysis and interpretation.