RACHEL MARTIN, HOST:
Last year, the Gulf of Maine saw the highest water temperatures ever recorded there. In fact, it's one of the fastest-warming bodies of water on the planet. Maine Public Radio's Fred Bever reports.
FRED BEVER, BYLINE: Data released by the Gulf of Maine Research Institute show that last year surface water temperatures in the Gulf were on average a half degree higher than the previous record. And the Gulf experienced what's called a marine heat wave the entire year.
The institute's David Reidmiller says it punctuates a decades-long trend that shows no sign of abating as the climate continues to heat up.
DAVID REIDMILLER: As unusually warm as 2021 was in a historical context, it's likely to be one of the coolest years we'll experience going forward.
BEVER: The Gulf extends from Cape Cod to Canada and is warming partly due to massive ice melt from the Arctic. That pulse of cold fresh water is changing the course of long-established ocean currents and allowing relatively warm Gulf Stream waters to push closer to New England's coast. The high surface-water temperatures are an indicator of change that observers are seeing throughout the Gulf's ecosystems.
Steve Train harvests lobster and grows seaweed off Portland.
STEVE TRAIN: My kids have been catching squid off the dock at night for years now. I never caught squid off the dock.
BEVER: He says warmer waters are bringing in more southerly species, and not just in summer.
TRAIN: We're catching sea bass in our traps frequently, you know, not occasionally, not just in the month of June or something. Last time we went out and hauled, we had two sea bass in 45 fathom of water. We didn't used to see that.
BEVER: The latest visitor Maine fishermen are seeing come 'round more often, even in winter? - what the South knows as the Chesapeake blue crab.
Gib Brogan is a fisheries analyst at Oceana, an international conservation group. He says that as marine species shift their territory in response to climate change, regulators will be challenged to keep up.
GIB BROGAN: I think very much the Gulf of Maine is going to be the crystal ball showing us the future of oceans management.
BEVER: And with the Gulf of Maine warming almost three times as fast as the planet's oceans overall, the researchers say it provides a glimpse of the future, not just for fishermen, but for ocean ecosystems and coastal economies worldwide.
For NPR News, I'm Fred Bever in Falmouth, Maine. Transcript provided by NPR, Copyright NPR.