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Tuna Treaties Fail to Stop Overfishing of the Imperiled Pacific Bluefin

Just two years after limits were imposed to help the recovery of decimated tuna populations – which have suffered an estimated 97% decline in recent decades – fishing quotas are being exceeded, much to the dismay of environmentalists.

Written by Matthew O. Berger Published on Read time Approx. 5 minutes
Pacific bluefin tuna
Pacific bluefin tuna. NOAA

In January, a single Pacific bluefin tuna sold for more than $670,000 at auction in Tokyo, the second-most ever paid for one of the prized fish, whose flesh is sought for sushi and other dishes.

Then in April another milestone was reached: Japanese fishers surpassed recently imposed Pacific bluefin catch limits with months still remaining in the fishing season.

Those limits were set in 2015 to aid the recovery of Pacific bluefin populations, which have declined by an estimated 97.3 percent in recent decades, due in large part to overfishing.

The Pacific bluefin – which race at speeds approaching 50 miles per hour, migrate 6,000 miles (10,000 km), exceed 9 feet (2.7 meters) in length and weigh up to 1,000 pounds (450kg) – play a key role in the ocean as an apex predator.

But the busting of the quotas revealed the limits of diplomacy in restoring the valuable, vulnerable fish: Even when agreements are reached to restrict fishing, they’re toothless unless enforced.

“There is absolutely insufficient enforcement,” said Amanda Nickson, director of Pew Charitable Trusts’ global tuna conservation project.

In 2014, the countries and territories that make up the Western and Central Pacific Fisheries Commission agreed to halve catches of immature bluefin, which haven’t yet had a chance to reproduce, in the western Pacific. Those quotas went into effect the following year.

But in April 2017, fishers in Japan, which catches the most Pacific bluefin, exceeded their quotas for the season ending in June.

The next month, Japan’s fisheries agency announced that those prefectures that had exceeded their quotas would be awarded additional allocations for immature bluefin, which will be deducted from next year’s catch limits.

“We have to ask, if they didn’t manage to enforce the quota this year, at what point will be they be able to enforce it next year?” said Nickson. “I’m sure that a country like Japan must have options to improve enforcement at a domestic level.”

But it’s not just Japan. The failure of internationally agreed quotas to limit the catch of bluefin appears to be part of a broader failure of international negotiations to restore tuna populations in the Pacific.

There are 33 member countries and territories in the Western and Central Pacific Fisheries Commission. That group and its eastern Pacific counterpart, the Inter-American Tropical Tuna Commission, which is made up of many of the same members, have consistently come under fire from conservation groups for not setting catch limits that would give bluefin the ability to recover from overfishing.

“What we’ve seen is a wholesale lack of action to the plight of bluefin,” said Nickson, who, along with other advocates, have called for a two-year moratorium on Pacific bluefin fishing.

But the recent quota overruns raise the possibility that even if the management organizations were to impose stricter catch limits or a moratorium on fishing bluefin, lax enforcement and underreporting of catch could undermine the efforts.

Where to go from here? Maybe back to the labs.

“The Pacific is so big, it’s difficult to manage,” said Stanford University marine biologist Barbara Block. “We have no clear way of managing Pacific bluefin in its current state.”

Block, who conducts tagging studies to learn more about tuna life history, said scientists still don’t know when Pacific bluefin spawn or exactly what the relationship is between the western and eastern Pacific populations. And they are only now nearing an answer on when the fish reach sexual maturity and reproduce. “Humans reach puberty at different ages, depending on nutrition,” she said. “And just because you’re sexually mature doesn’t mean you’re spawning.”

It’s known that Pacific bluefin are born in Japanese waters, then feed for several years off California and Mexico before returning to Japan to spawn. But details of that 6,000-mile migration remain a mystery, as does what fish are being caught when and by whom.

Alfred Cook, tuna program manager for WWF-New Zealand, noted a couple more unknowns: the effect climate change is having on the fish and the extent of illegal and unreported bluefin fishing. “Whether it’s too late is hard to say due to those various uncertainties, but what we do know is that, if we gave the Pacific bluefin stock a fighting chance, it is generally very resilient and could recover in a relatively short period of time,” he said.

Nickson agrees. “This is a population that can recover,” she said. “If this species doesn’t recover, that will be a political decision.”

A temporary moratorium would give the Pacific bluefin the opportunity to bounce back, according to Nickson. As would capping the catch of sexually immature fish at lower levels than the current limits, which she says could give populations a boost within three to five years. “But now (countries) can’t even be held to the higher quotas,” she said.

Catch limits negotiated through the international fishery management organizations have proven ineffective in giving bluefin that chance at recovery, Cook said. A moratorium would simplify the issue. “Around 80 percent of Pacific bluefin harvested goes into Japan,” he said. “If Japanese markets refused to accept Pacific bluefin, the issue could be solved virtually overnight.”

If regulatory or diplomatic solutions are going to be effective, though, they’ll need enforcement. The International Commission for the Conservation of Atlantic Tunas, which manages tuna in the Atlantic Ocean, slashed quotas for the endangered eastern Atlantic bluefin in 2009 and kept them low through 2014, earning praise for spurring a population rebound. But the quotas – and criticism from conservationists – have increased in recent years.

Block chalks up the bounce-back of the Atlantic bluefin to an “awakening” over the past several years. “In the Atlantic, we’ve seen a lot of investment in recent years to manage it better, “ she said. “In the Pacific, there’s still a lot of unknowns. There’s a general lack of transparency on what’s being caught, and that needs to improve.”

The biggest difference may be the implementation of an electronic catch reporting system last year in the Atlantic. Every bluefin caught there now is supposed to be registered in a database, which is updated each time the fish changes hands, giving managers near real-time updates on the harvest and undercutting the ability to sell illegally caught or unreported tuna.

That electronic reporting technology is “ready for prime time,” Cook said, adding that soon “there will be no reason that every piece of every fish, especially bluefin, is not traceable from boat to throat.”

But such an e-reporting system does not yet exist on either side of the Pacific.

The reason? “In short, politics,” Cook said.

Diplomacy continues, though. On June 5 at the United Nations Ocean Conference in New York City, 50 tuna retailers and wholesalers, five South Pacific island nations and 19 foundations and environmental groups signed a declaration calling for the full traceability of tuna by 2020. “Tuna products in our supply chains will be fully traceable to the vessel and trip dates, and that this information will be disclosed upon request at the point of sale either on the packaging or via an online system,” the declaration stated.

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