An Unexpected Recovery of The Bluefin Stocks Has Created an Amazing Fishery in Southern California, But Will It Last?

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The story of the management of the stocks of Atlantic bluefin tuna (Thunnus thynnus) could fill several large novels. Since the 1960s, when the commercial fishery for these prized fish skyrocketed, we have struggled to find the right balance between satisfying the huge commercial demand and maintaining a stock healthy enough to support a vibrant recreational fishery as well.

Those recreational fisheries became legendary well before the commercial boom threatened the species. As early as the 1930s, intrepid anglers eager to tangle with these truly big and powerful fish traveled to Bimini and Cat Cay in the Bahamas, along with New England and Nova Scotia, in the hopes of landing one. Few other fisheries offered realistic shots at fish over 1,000 pounds. Years later, a new bluefin fishery discovered off the Outer Banks of North Carolina brought these magnificent fish within reach of a whole new generation of anglers.

Depending on who you talk to, Atlantic bluefin are either almost extinct, more plentiful than ever, or somewhere in between. “In between” makes the most sense, but because of the extreme high value of the fishery, we’ve studied it intensely for a long time and know more than ever about the fish and how they live. For instance, estimates of their life expectancy have changed substantially, and we now know that two breeding stocks exist where before it was assumed only one existed, in the Mediterranean Sea.

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New Breeding Grounds

Scientists discovered that the Gulf of Mexico also served as a major breeding ground, perhaps answering the question of where all the giant bluefin caught at Cat Cay came from. The Straits of Florida lead directly from the Gulf, around Key West, Florida, and northward to the west of the Bahamas. It seems a natural migration route for the fish and would lead to all the other spots where the fish are often encountered.

But the Pacific bluefin (Thunnus orientalis) has remained more of a mystery. Pacific bluefin spend most of their time in the northern hemisphere and should not be confused with Southern bluefin (Thunnus maccoyii), which live in the southern hemisphere. Once found off Southern California in the 1950s, the Pacific bluefin disappeared and were scarcely seen for decades.

Prior to 2016, catches of larger bluefin in California were rare, if they occurred at all. Decades of commercial overfishing, primarily by Japan and Mexico—who catch the most Pacific bluefin across its range—had driven down the bluefin biomass to a historic estimated low of two percent of its potential unfished level. Then something startling occurred.

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A Once-Vibrant Fishery Returns

“For most of my angling life in Southern California, larger Pacific bluefin tuna were non-existent in our waters,” said Bill Shedd, CEO of the American Fishing Tackle Company (AFTCO). “But then in 2016, the fish suddenly showed up again in incredible numbers. It was unbelievable. Almost overnight, a reliable fishery was established, bringing with it a tremendous economic boon to this area.”

Shedd said the Inter-American Tropical Tuna Commission (IATTC), the international treaty organization that manages Pacific bluefin, began lowering the commercial quotas in 2012, resulting in the population being rebuilt to an estimated 22 percent of its potential unfished level—a goal reached 10 years ahead of schedule.

Shedd and others have compared this to what happened in Florida when longlines were removed from much of the South Atlantic Bight, leading to a swordfish stock recovery and another recreational economic boost.

“Overall, the stock of Pacific bluefin is improving due to management measures put in place following the depletion of the stock over generations,” said Dr. Bruce Pohlot, Director of Conservation for the International Game Fish Association (IGFA). “This improvement has resulted in improved catch rates in the recreational fisheries, especially in Southern California, and improved abundance numbers across the range of the stock.”

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A Huge Economic Impact

“One does not need to live in California to know what a huge impact the return of large bluefin tuna to California waters has had on the sportfishing and boating community, in California and beyond,” Shedd said.

Today, sportfishing for Pacific bluefin in California is the best it has been in anyone’s memory, benefitting both the industry and anglers. However, as good as the fishery has been, there are some dark clouds on the horizon.

Unfortunately, we are already on a path toward another potential Pacific bluefin crash if increasing quotas are allowed to go unchecked. Recently, IATTC, with NOAA as part of that body, increased the U.S. commercial Pacific bluefin quota by almost 80 percent—from 1,017 metric tons (mt) in 2023-2024 to 1,822 mt in 2025-2026. This follows an increase from the 2021-2022 quota of only 730 mt.

Even more concerning is the Mexican commercial bluefin quota for their purse seine fleet. They catch the bluefin before they reach the U.S., and their quota is set to increase from 6,973 mt in 2023-2024 to 10,763 mt in 2025-2026.

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Rapidly Increasing Quotas Threaten the Return

“We have concerns that as the numbers grow, we will see increased allowances for commercial fisheries across the North Pacific,” Pohlot said.

A major concern is the reliance on outdated age-of-maturity estimates. Current management assumes Pacific bluefin spawn at three to five years, but research suggests they may spawn much later—similar to Atlantic bluefin, which spawn at six to eight years. If this is the case, harvesting younger fish could devastate the stock.

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Better Science Needed

Pacific bluefin spawn in the Sea of Japan. At about one year old, a portion of the spawn migrates east to feed off Baja California, then follows a seasonal migration up to Monterey, California, and back down to Baja. Once they reach spawning age, they return west to Japan.

Dr. Barbara Block has been tagging larger Pacific bluefin with satellite tags to determine their actual spawning age. Initial findings suggest they may not return to Japan to spawn until much later than previously thought. This research is crucial and requires more funding from NOAA to reach definitive conclusions.

“The positive outcome of recent stock assessments in 2022 and 2024 for Pacific bluefin is reassuring,” Pohlot said. “But because spawning stock biomass (SSB) remains at a low percentage of unfished levels, any increases to catch limits should be treated with caution.”

Recently, the IGFA urged the Western and Central Pacific Fisheries Commission (WCPFC) to consider the economic impacts of the increase in recreational fishing effort occurring in the Pacific, especially off southern California, and to consider efforts to utilize the recreational fishing community to obtain crucial catch-and-release data on juvenile Pacific bluefin. “The significant economic impact attributed to increased recreational fishing for bluefin in southern California can be seen in other areas if catch-and-release fishing has an opportunity to grow,” Pohlot added.

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Recreational Input Needed

“The sport-fishing community must demand participation in the decision making and management of Pacific bluefin,” Shedd said.  “If we don’t do so, I am concerned that overfishing by foreign commercial interests will once again crash our bluefin fishery.  Currently, we rely on NOAA Fisheries to speak for our interests with no real input or push from us. That is problematic at best. Further complicating the future of Pacific bluefin is the fact that the current management process relies on outdated and inaccurate science developed by Japan that fits the self-interest of their commercial fleets.” 

Shedd says there are two basic things we can do to help prevent a future Pacific bluefin population crash.  “First, we need to register our concern for the growing Mexican and American commercial quotas within IATTC,” he said.  “And second, we need to better understand the actual spawning age of Pacific bluefin.” Research to determine a more accurate spawning age range for the bluefin will continue with Dr. Block and others and will hopefully lead to a more accurate data set and better science outcomes for managers.

And on the economic impact front, Rob Southwick of Southwick and Associates is reportedly gearing up to do a full evaluation of the economic impact this recently developed fishery has created. Southwick has long been the go-to economist in terms of identifying the substantial economic benefits created by recreational fishermen. For example, in similar fashion to how offshore tackle sales soared in Florida when the swordfish stocks recovered, so have the sales of such gear in Southern California since the bluefin returned in 2016.

Management Recommendations

“The IGFA recommends the Commissions (WCPFC and IATTC) take the following steps to protect Pacific bluefin stocks,” Pohlot said. “They should take a precautionary approach to potential increases in catch limits by not significantly increasing those limits and ensure rebuilding targets continue to be met in the coming years. They must also continue to monitor Pacific bluefin spawning stocks and recruitment to ensure model assumptions are validated moving forward and ensure catch overages do not occur by urging nations to implement domestic catch limitation measures. And they should reevaluate age at maturity parameters for Pacific bluefin and explore available science to determine accurate age at maturity, similar to Atlantic bluefin tuna, as we believe that most fish caught are juveniles that have not had a chance to spawn.”

It seems obvious that history is trying to repeat itself as the Pacific bluefin potentially head toward the same fate that their Atlantic cousins have endured for so many years. The good news this time is that we have the chance to act proactively to keep that same cycle from returning, and lots of good people like Bill Shedd, Dr. Bruce Pohlot and many others are vigilantly on the case, trying to stop history in its tracks.

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