Fisheries regulators and the seafood industry are grappling with the possibility that some once profitable species that have declined with climate change may not return.
Several marketable species harvested by U.S. fishermen face quota cuts, seasonal closures and other restrictions as populations have plummeted and waters have warmed. In some cases, like the bottom fishing industry for species like plaice in the northeast, the changing environment has made it harder for fish to recover from years of overfishing that have already taxed the population. .
Authorities in Alaska have canceled the fall harvest of Bristol Bay red king crab and the winter harvest of snow crab, dealing a blow to the Bering Sea crab industry that is sometimes worth over $200. millions of dollars a year, as populations have declined in the face of warming waters. The Atlantic cod fishery, once New England’s vital industry, is now essentially closed. But even with depleted populations threatened by climate change, it’s rare for regulators to completely shut down a fishery, as they plan to do for New England shrimp.
Northern prawn, once a seafood delicacy, has been under a fishing moratorium since 2014. Scientists believe warming waters are wiping out their populations and they won’t return. So the Atlantic States Marine Fisheries Regulatory Commission is now considering making this moratorium permanent, essentially ending the centuries-old shrimp fishery.
It’s a brutal siren for several species caught by American fishermen who regulators say are on the brink. Others include clams, winter flounder, Alaskan snow crabs and chinook salmon.
It’s hard to say exactly how many fisheries are primarily at risk from warming waters, but further reductions and closures are likely in the future as climate change intensifies, said Malin Pinsky, director of the program. graduate studies in ecology and evolution at Rutgers University.
“This pattern of climate change and how it impacts coastal communities and economies is something we have to get used to,” Pinsky said. “Many years are pushing us outside of what we have experienced historically, and we will continue to observe these new conditions as the years go by.”
While it’s unclear if climate change has ever been the dominant factor in the permanent closure of a US fishery, global warming is a major reason why several once-robust fisheries are increasingly in danger. poor condition and subject to more aggressive regulation in recent years. Warming temperatures introduce new predators, force species to shift their population centers north, or make it more difficult for them to grow to maturity, the scientists said.
In the case of the northern shrimp, scientists and regulators said at a meeting in August that the population had not rebounded after nearly a decade without commercial fishing. Regulators will revisit the possibility of a permanent moratorium this winter, said Dustin Colson Leaning, fisheries management plan coordinator at the Atlantic States Commission. Another approach could be for the commission to relinquish control of the fishery, he said.
Shrimp prefer cold temperatures, but the Gulf of Maine is warming faster than most of the world’s oceans. Scientists say warming waters have also moved new predators into the gulf.
But in Maine, where the cold-water shrimp fishery is based, anglers have tried to argue that shrimp abundance is cyclical and any decision to permanently close the fishery is premature.
“I want to look at the future of this. It’s not unprecedented to have shrimp loss. We went through it in the 50s, we went through it in the 70s, we had hard times in the 90s,” said Vincent Balzano, a shrimp fisherman from Portland. “They came back.”
Another endangered species is the winter flounder, once highly sought after by anglers in southern New England. The National Oceanic and Atmospheric Administration described the fish as “significantly below target population levels” on Georges Bank, a key fishing area. Scientists from the University of Rhode Island and the Rhode Island Department of Environmental Management wrote that fish were struggling to reach maturity “due to increased predation associated with warming winters” in a report by Last year.
On the West Coast, chinook salmon face a risk of extinction due to climate change, NOAA reported. The drought has worsened the prospects for the fish in California, at the southern end of its range, scientists have said.
East Coast fishermen from Virginia to Maine have been digging clams out of tidal mud for centuries, and they’re a staple of seafood restaurants. They’re used for chowder and fried clam dishes. and are sometimes referred to as “steamers”.
But the clam harvest has fallen from about 3.5 million pounds (1.6 million kilograms) in 2010 to 2.1 million pounds (950,000 kilograms) in 2020, as the industry has had to deal with an aging workforce and increasing competition from predators such as crabs and worms. Scientists have linked the growing threat of predators to warming waters.
Maine’s 2020 haul, which harvests the most clams, was the smallest in more than 90 years. And catches in 2021 still lagged behind typical catches in the 2000s, which were consistently near 2 million pounds (907,000 kilograms) or more.
Predicting what the 2022 clam harvest will look like is difficult, but the industry remains threatened by the growing presence of invasive green crabs, said Brian Beal, professor of marine ecology at the University of Maine at Machias. Crabs, which eat clams, originated in Europe and arrived in the United States about 200 years ago and have increased in population as the waters have warmed.
“There seems to have been, compared to 2020, a ton more green crabs settling in,” Beal said. “It doesn’t bode well.”
One of the challenges of managing declining fisheries due to warming waters is that regulators rely on historical data to set quotas and other regulations, said Gulf of Maine senior researcher Lisa Kerr. Research Institute in Portland, Maine. Scientists and regulators are learning that some fish stocks simply aren’t able to return to the level of productivity 40 years ago, she said.
At the time, American fishermen typically caught more than 100 million pounds (45.4 million kilograms) of Atlantic cod annually. Today, they typically catch less than 2 million pounds (907,000 kilograms), as overfishing and environmental changes have prevented the population from returning to historic levels.
The future of managing species in such poor condition may require accepting the possibility that it may not be possible to completely rebuild them, Kerr said.
“It’s really a reset of expectations,” she said. “We’re starting to see more consistent goals, but lower than a lower overall goal.”