Atlantic bigeye tuna is approaching collapse: fishery managers must act now

While seafood is an important source of nutrition for people around the world, sometimes the demand for fish is too high and we take more from the water than we should. That’s the case with Atlantic bigeye tuna, a clear-cut example of a species that has been overfished – and a species whose outlook can be improved only if policymakers with the ability and proper authority take rapid action.

This fast-swimming species, which starts life small enough to swim through the eye of a needle and can grow to more than 180 kilograms in just a few years, is one of the most fished tunas. Juveniles are caught and processed to sell in cans while adults are typically pursued for their value to high-end sushi markets. Fishing operations throughout the Atlantic Ocean – from Canada to Brazil and from Western Europe to South Africa – catch, keep, and sell Atlantic bigeye.

Bigeye can be a very lucrative catch. After the iconic Atlantic bluefin tuna, which can go for tens of thousands of dollars per fish, the Atlantic bigeye is the next priciest tuna –worth about US$300 million per year to fishers in the region and closer to US$1 billion at the final point of sale.

Bigeye fisheries are far less regulated than bluefin fisheries. So it’s no surprise that financial opportunity, combined with insufficient oversight and monitoring, has led to a steep decline in the bigeye population; steep enough for scientists from the International Commission for the Conservation of Atlantic Tunas (ICCAT), the body that manages bigeye fishing, to sound the alarm.

A new assessment of the size of the bigeye population conducted by these scientists concludes, with 99.5 percent certainty, that decades of fishing have depleted the population and that fishing pressure on the species remains far too high. If fishery managers allow business as usual to continue, the population is 60 times more likely to totally collapse within the next 15 years than to recover to sustainable levels. Nature will not fix this problem for us. That’s the bad news. The good news is that the 52 governments that make up ICCAT can.

Time to stop the decline

ICCAT representatives will meet from 12 to 19 November in Dubrovnik, Croatia, tasked with addressing this challenge. The European Union – particularly Spain, France, and Portugal – as well as Japan, Brazil, and the other big players in Atlantic bigeye fisheries, have to find a science-based solution that ends the decline and rebuilds the stock. If government representatives come to the meeting unwilling to take the necessary steps to recover bigeye, it will be nearly impossible to reach a consensus on science-based management for the stock.

ICCAT scientists have recommended that members urgently address overfishing. Based on the current stock levels, Pew urges ICCAT managers to reduce the catch from current levels of approximately 79,000 metric tons per year to 50,000. This move would give the stock a 70 per cent chance of recovering in 10 years. Europe, in particular, should have no objection to this goal since a catch level this size has a 50 per cent chance of ending overfishing by 2020 – a percentage and date that is consistent with the EU’s Common Fisheries Policy that binds all member states.

In addition to cutting quotas, ICCAT managers must work to reduce the high catch of juvenile bigeye, which are taken before they can reproduce, most often by purse seine vessels that rely on fish aggregating devices to catch tuna. The majority of these vessels are owned by Europeans, but some are reflagged, for a lucrative licensing fee, by Curacao, El Salvador, Cabo Verde, Belize, and other countries.

If the Dubrovnik meeting ends without a strong bigeye recovery plan, the outlook for this tuna is poor.

The catch will remain too high, and collapse could be imminent. However, if ICCAT adopts a rebuilding plan with a high probability of recovering the bigeye population within the next 10 years – one that includes strong monitoring, control, and surveillance of fishing to ensure illegal activities are not taking place – the stock will grow, fisheries will improve, and fishers will continue to earn money. And if that happens, managers will demonstrate that they’re serious about science-based management of this valuable species. After years of neglect and unsustainable fishing, it’s time to give bigeye populations a chance to recover.