The Demise and Recovery of The Atlantic Bluefin Tuna

Bluefin tuna is one of the iconic species of big game fish. It is a large-bodied fast swimming fish that feeds on small fish and invertebrates. It can grow up to 1500lb (800kg) although some official bodies like the Smithsonian or the U. S. National Marine Fisheries Service estimate that the fish can reach a weight of over 2000lb. When swimming it can reach speeds of up to 65 km/h. There are three recognised subspecies: Atlantic bluefin tuna, Pacific bluefin tuna and Southern bluefin tuna, though sometimes the longtail tuna is also included in this list. In this story, we are focusing on the Atlantic subspecies.

The Atlantic bluefin tuna was severely overfished due to its high commercial value. In 2009 the ICCAT (The International Commission for the Conservation of Atlantic Tunas – an intergovernmental organisation responsible for the conservation of tuna and tuna-like species) recognised that the Eastern Atlantic and Western Atlantic stocks had declined by 72% and 82% respectively. Some protection measures were proposed but the usual jostling between governments ensued.

The latest data I was able to find indicates that the scientists recommend a global quota of 15,000 tonnes to maintain current stocks or 10,000 tonnes to allow them to recover. However, the ICCAT set the quota at 36,000 tonnes with independent surveys suggesting that up to 60,000 tonnes were actually taken. Subsequently, the latest scientific recommendation was set to 7,500 tonnes as a sustainable limit.

The first time I got interested in the bluefin tuna situation was in the early 2000s. That was around the time when I heard the term “the economy of extinction”. When the news broke that the species might go extinct, Japan’s Mitsubishi Corporation, which handles 40% of Japan’s imported Atlantic bluefin tuna, reacted by tripling its deep-freezing capacity. If the fish were to go extinct, they would be sitting on stockpiles of frozen tuna, the price of which would be shooting through the roof. For them, driving the species to extinction would be nothing more than a good business move.

Around that time I also learned that bluefin tuna used to be commonly caught in the waters around Ireland. I saw the reminders of these times while travelling around the country for my shark fishing charter trips. Every now and then I got to talk to a charter skipper who used to do tuna trips. Some of the skippers even had their boats equipped with fighting chairs and swivelled rod holders for that purpose. Now they had all been removed from their boats and were sitting unused, gathering dust in storage.

However, in the mid-2010s, bluefin tuna started to appear again in the English Channel and off the West coast of Ireland. A few years later, in 2019, Inland Fisheries Ireland, in collaboration with other agencies (the Marine Institute, the Department of Fisheries and Marine, and the Department of Climate Change and Environment) launched the Tuna CHART (CatcH And Release Tagging) program which is a part of a wider program managed by ICCAT. The aim of the program is to gather data about bluefin tuna with the help of anglers and selected, experienced charter skippers.

To learn more about the Tuna CHART program listen to my conversation with a senior research officer at Inland Fisheries Ireland, Dr William Roche. During our chat, we not only discuss the program but also details of bluefin tuna angling. We also touch on the Marine Sportfish Tagging Programme, which is the gold standard of tagging programs, aimed at research and promotion of the conservation of elasmobranch species of fish: sharks, skates and rays.

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