A new study by Hawaii scientists, released in October, reached an intriguing conclusion: No-fishing zones can increase the number of migratory fish that travel far beyond those boundaries.

The study, published in the journal Science, found that the number of bigeye and yellowfin tuna caught by fishing boats outside and near the Papahanau- mokuakea Marine National Monument (PMNM) increased significantly after the protected area was expanded in 2016. It’s not conclusive proof that the expansion led to a broad increase in the tuna population; other factors could be at play. But establishing a cause-and-effect would make a strong argument for expanding such reserves.

It also would undercut arguments by commercial fishing interests that marine reserves harm their industry, as well as the economies of small island nations that depend on it — not to mention Hawaii’s longline fleet, which feeds our appetite for ahi poke.

So it’s no surprise that the Western Pacific Regional Fishery Management Council (Wespac), a staunch supporter of commercial fishing and consistent opponent of no-fishing zones, would challenge the study.

“When we look at all of the data, we simply don’t see what they estimated,” said Ray Hilborn, a member of the council’s Scientific and Statistical Committee (SSC), which attempted to replicate the study’s results. “In general, CPUE (catch per unit effort) increased faster the farther away you are from the PMNM after the closure — this is the opposite of what the paper says,” he said.

The study’s authors pushed back, accusing the SSC of “cherry-picking” the data to spin its conclusions.

Regardless, what is not in dispute is that overfishing can decimate marine species, sometimes beyond recovery. Hawaii’s longline fleet has made considerable progress in addressing this problem, achieving certification by the Marine Stewardship Council for adopting sustainable practices in its swordfish, bigeye and yellowfin tuna fishery. That’s all to the good. But one thing needs to be clear: The long-term management of the Pacific Ocean’s ecosystems cannot be based solely, or even primarily, on the short-term interests of commercial fisheries and their ability to catch as many fish as they can.

In fact, a global effort to protect and conserve at least 30% of oceans, lands and freshwater by 2030 recognizes the complexity and rich diversity of the natural world, which we depend on in ways still not clearly understood.

There’s also the threat of climate change and warming oceans, which could fundamentally alter marine biodiversity. Scientists have found that marine protected areas can help stabilize what we still have for future generations. That’s worth pursuing, even if we get to eat less poke.