World conflict is likely to increase over access to fisheries, as species move north in response to a warming ocean, according to a Rutgers University study published last week in the journal Science.
“Seventy or more countries will likely have to start sharing with their neighbors” in coming decades, said lead author Malin Pinsky, including the U.S., Canada and Mexico.
The danger comes from overfishing when countries can’t cooperate, he said. Consumers and economies are harmed by overexploitation.
“If there’s a fish fight, you end up with less fish for everyone — less fish on every plate, fewer jobs for local economies and less profit for local businesses,” said Pinsky, 37, an assistant professor in Rutgers’ Department of Ecology, Evolution and Natural Resources who is soon to be an associate professor.
The right to harvest particular species of fish is usually decided by national and regional fishery management bodies, which assume species don’t move much, Pinsky said.
“Well, they’re moving now because climate change is warming ocean temperatures,” he said. Studies have estimated the oceans have absorbed about 93 percent of recent increases in global temperatures.
Fish are shifting into new territory at a rate averaging 43.5 miles per decade, and these shifts are expected to continue or accelerate, his study found.
Some species have already moved considerable distances.
When Atlantic mackerel moved into Icelandic waters around 2007, Icelanders started to fish them along with fishermen from the European Union, who had traditionally had the mackerel to themselves.
“They couldn’t agree on how to share the catch,” said Pinsky, a Princeton resident who grew up close to the coast in Maine. “The combined competitive race to fish ended up overfishing that population.”
The fishery conflict escalated into a trade war that affected Iceland’s decision not to join the European Union.
“Spillover from what can seem like a small, distant issue becomes much bigger,” Pinsky said.
Conflicts are already erupting in the U.S., as fish have pushed across state boundaries.
“There’s quite a vigorous debate now between states about access to the summer flounder fishery,” Pinsky said, “as there has been a northern shift in (the species).”
The epicenter of the fishery used to be off Virginia but is now 250 miles farther north, off New Jersey and New York.
Gregory DiDomenico, executive director of the Garden State Seafood Association, said northern states such as New York argue they should now get a larger allotment for their fishing industries.
He said allotments, which are set by the Atlantic States Marine Fisheries Commission and the Mid-Atlantic Fishery Management Council, are based on the history of landings by state.
But DiDomenico thinks people are misusing studies such as Pinsky’s to argue they should get a bigger share of the fishery.
The location of species shouldn’t matter, he said.
“People from northern states, including New York, are claiming that the so-called geographical changes in fish stocks is a justification for taking fish from other states,” DiDomenico said. “We don’t see it that way. New Jersey, Virginia, and North Carolina have always gone to where fish are. We are very unhappy at this approach.”
Some species are simply expanding their range into a new habitat, while others, such as lobster, are expanding poleward and leaving areas where they were found traditionally.
The center of the offshore lobster distribution used to be off northern New Jersey, Pinsky said. Now it’s off the Gulf of Maine.
Pinsky said warming ocean temperatures, shell diseases and new predators all appear to be playing a role in lobsters’ northward shift.
“Much of the underlying driver is warming,” he said.
DiDomenico said there is probably a host of things causing the local lobster fishery to decline, including water quality.
“Not everything is explained by climate change,” DiDomenico said. “Some of it is related to management. That goes for fin fish as well.”
Predators are also moving north, and new ones are now nipping at the heels of the lobster in places where they didn’t used to face them. Important offshore predators such as black sea bass have moved north and are predating lobster, Pinsky said.
Lobster in the Gulf of Maine haven’t had to deal with predators for decades. Cod had been an important lobster predator there but were overfished, so the population fell dramatically, he said.
Another example is tilefish, Pinsky said. For years, fishing regulations only applied south of Cape Hatteras, North Carolina, since that was traditionally the northern part of the tilefish range. But in the early 2000s, the species showed up in new places.
“For nearly a decade, there was a fishery north of there. But there were no rules,” Pinsky said.
That changed in 2015, when the Mid-Atlantic Fisheries Management Council instituted emergency rules for more northern states, he said.
Political entities often don’t have a good process for how to start sharing the wealth that comes as new fisheries emerge, Pinsky said.
“That’s what we are calling for in this paper. We are saying we know already there is a problem. It’s going to become bigger in the future. So we need to set up those mechanisms now for sharing information and science on where the fish are, and make decisions on how to divide the catch equitably and fairly so there isn’t a race to fish.”