The Great Tuna Gamble

North Lake is a sleepy harbor village of a few dozen wooden fishing shacks and a handful of houses, perched on the northeastern shore of Prince Edward Island on the east coast of Canada. When your correspondents visited in the summer of 2015, action was sparse. Fishers loaded and unloaded small boats, dogs ambled around stacks of wooden lobster traps, and the occasional flip-flopped tourist wandered by, looking for a boat for hire.

Despite the town’s modest appearance, a sign hanging from the office of the Harbor Authority declares North Lake to be the Tuna Capital of the World. The tuna to which the sign refers are giant Atlantic Bluefin: famed fish that can fetch tens of thousands of dollars each, destined for the plates of Japan’s wealthy and powerful; fish that draw big game hunters from around the world to this small community.


Yet whether North Lake, or anywhere really, can maintain a status of Tuna Capital depends on what happens to the stock of tuna itself. After decades of overharvesting, Atlantic Bluefin are endangered, according to the scientists at the International Union for the Conservation of Nature. Despite a recent uptick in the size of the stock, Atlantic Bluefin still number no more than half of their 1970 levels.

The plight the Bluefin can be attributed mainly to actions of the International Commission for the Conservation of Atlantic Tunas (ICCAT), an intergovernmental organization formed in the late 1960s, comprised of representatives from 50 countries involved in the harvesting of tuna and tuna-like species in the Atlantic. Under the watch of ICCAT, which sets the total allowable catch for Atlantic tuna species, western and eastern Atlantic Bluefin populations dropped precipitously, to roughly 17% and 33% of their pre-1950 levels respectively by the late 2000s.

By 2010, the problem could no longer be ignored. A number of countries tried to have the international trade in Bluefin (and consequently, most Bluefin fishing) banned outright under the Convention on International Trade in Endangered Species (CITES) treaty. This motion was defeated by fishing nations who argued that the species could be responsibly fished back to health. Sure enough, in 2010 quotas for both the eastern and western stock were reduced, and Bluefin numbers have since registered a small increase.


Keen to enjoy the rewards of restraint, in 2014 ICCAT announced that quotas would increase by roughly 20 percent each year, from 2015 until 2017. The latest increase was approved at the ICCAT annual meeting in Malta just last month.

Arguably, these increases have occurred in line with scientific recommendations. At the Malta meeting, environmental groups – some of the same groups which demanded the CITES ban in 2010 – expressed their cautious support for ICCAT’s actions. That the 2014 plan was being adhered to, and that the plan had been informed by science, was seen as a victory.

Certainly, ‘following the science’ is a welcome development. Past years, in contrast, saw ICCAT negotiators overshooting the advised numbers with abandon. However, ‘following the science’ is only a victory if the goal that the science tries to achieve is one we consider acceptable. When the species is listed as endangered, it’s worth asking what the goal is.

In essence, ICCAT’s plan is to achieve a stock size that will deliver the ‘maximum sustainable yield’ by 2022, and to do so with a probability of at least 60 percent. This target is a noble ambition, but the odds of success that ICCAT considers acceptable are not much better than a coin flip.

In an uncertain world that does not leave much room for error.

There are three sources of uncertainty regarding the Bluefin’s future. Firstly, scientists warn that the stock estimates have a high margin of error. One reason for this is that no one knows the extent of mixing between the Bluefin populations in the western and eastern Atlantic, leading to questions about how to define Bluefin stocks in the first place: is there one or are there two? The good news is that a new method of assessing the stock should be ready by next year. Given that, however, it would seem prudent to hold off on considerable increases in the quota until the improved information is at hand.

Secondly, illegal and unreported fishing is still a problem, meaning that the total allowable catch – which is set to allow the species to recover – is likely being exceeded, and by an unspecified amount. ICCAT has designed a new electronic tagging system to counter the trade of illegally-caught fish, a system planned for implementation this year. But after delegates at the Malta conference decided to extend the completion date for the project to 2017, the harvest increases should, arguably, have been delayed as well. At the very least, the incentive of an increase in quota would have kept the pressure on countries to implement the system more quickly.


The third source of problematic uncertainty is that the oceans themselves are warming. This may spell a change for Bluefin, which have particular water temperature preferences and which feed on fish that are also influenced by water temperature. In 2012, a group of (greatly surprised) fishermen and biologists caught Bluefin off the coast of Greenland, in waters traditionally too cold to attract the fish. It was an unprecedented event. Whether this dramatic migration north represents a species in trouble is not known. But research is beginning to suggest that Bluefin will not escape the effects of climate change.

Undoubtedly, one can be cautiously optimistic about the future of one of the world’s most iconic fish. Despite grim predictions of impending extinction just 5 years ago, Bluefin stocks appear to be increasing. Modern tracking systems, with the potential to quash illegal fishing, are in the works. ICCAT appears surprisingly functional for a body comprised of 50 diverse countries with varying interests. All things considered, the docks at North Lake – the Tuna Capital – are unlikely to fall silent anytime soon. Two cheers, then. But save the third for when, or if, fishing nations hit their 2022 target, with its 60 percent chance of success. In a changing world, for an endangered and valuable species, that’s still quite a gamble.

Photos ©2015 Stephanie Simpson.

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