STONINGTON, Conn. — For the better part of a half-century, the waters of Long Island Sound allowed Michael Grimshaw a good living. Now, he’s holding fast to a dwindling hope that the ocean’s bottom still has something – anything – to give.

Grimshaw is believed to be the last full-time commercial lobsterman in Connecticut – still plying a fishery that was once thick with boats and rich with opportunity.

His youngest son preparing bait and his elderly, former mother-in-law readying claw bands, Grimshaw, 65, prodded his aging boat into the choppy harbor late one summer morning, well after most fishermen have put to sea.

Suited up in his wet gear, he was soon hauling up traps from the dark waters, one after another. Out of 10 traps, he snared some spider crabs and a few pogies. None contained a lobster.

“It’s embarrassing – terrible, really,” said Grimshaw, who continues to raise hundreds of traps a week, even though he claims to have retired. “I used to be the big dog; now, I’m the puppy.”

During his glory days in the late 1990s, when he competed with hundreds of other commercial lobstermen in the area for a multimillion-dollar annual catch, his traps used to bring up as much as a few thousand pounds a day of the coveted crustaceans. A good day now amounts to maybe 50 pounds.

Roderick Grimshaw pushed an empty lobster trap to the stern as Michael Grimshaw hauled up the rest. Jessica Rinaldi/The Boston Globe

The main culprit? Climate change.

Average surface temperatures in the Sound, a sliver of ocean between Connecticut and Long Island, N.Y, surged nearly 6 degrees Fahrenheit between 1982 and 2020 – with annual warming more than three times higher than the average of the globe’s oceans, according to data collected by the National Oceanic and Atmospheric Administration. That is, by comparison, twice the pace of warming in the Gulf of Maine, which scientists consider among the fastest warming bodies of water on the planet.

Even more concerning for fishermen has been the rise in marine heat waves – sustained periods of heightened water temperatures – which have made the Sound increasingly inhospitable to shellfish and more inviting to predators that were rarely seen so far north until recent years. For example, in 1982, the Sound had zero heat wave days; last year, there were 181 such days.

Lobster, in particular, thrive in narrow bands of temperatures. When the water exceeds 68 degrees, they’re prone to heightened stress that can make it difficult for their shells to grow. Last year, there were 105 days when temperatures exceeded that dangerous threshold.

“Long Island Sound is no longer a great place for lobster to live,” said Colleen Bouffard, a biologist in the fisheries division of the state’s Department of Energy and Environmental Protection.

For lobstermen in Connecticut, the years of warming have been devastating.

Roderick Grimshaw is reflected in the window of the Lady Lynn, his father’s boat. Jessica Rinaldi/The Boston Globe

At the peak of their catch in 1998, the state’s fishermen landed more than 3.7 million pounds of lobster, valued at more than $12 million, according to state records. By 2019, landings had plummeted to little more than 111,000 pounds, which earned Connecticut lobstermen just $675,000, according to the most recent data available.

Over the same period, fish that typically dwell in the warmer mid-Atlantic have been increasingly present in the Sound, where they feed on juvenile lobster. Landings of black sea bass, for example, increased by nearly eight times between 1998 and 2019. Having new fish to catch, however, hasn’t compensated for the decline in lobster, with last year’s overall landings netting Connecticut fishermen more than three times less than the peak in the 1990s.

With that decline came the collapse of the fishing fleet. The number of licenses issued to commercial lobstermen has dropped by nearly 80 percent since the 1980s, but Michael Grimshaw and a few others held on.

Judy Pont, Michael Grimshaw’s former mother-in-law, puts on her oil pants before heading out to band lobster for Grimshaw. Jessica Rinaldi/The Boston Globe

“We’re victims of climate change,” said Grimshaw, who noted the warming waters have also reduced oxygen levels in the Sound. “It hasn’t played out good for us.”

As he moved between trawl lines on Stonington Harbor, his son and former mother-in-law had little to do, as most traps came up empty.

When asked why she still fishes with her former son-in-law, Judy Pont said she knew he could use the help – and the company – especially after Grimshaw suffered a stroke last winter. The only payment she’ll accept, she said, are a few lobsters, which she often gives to friends.

Judy Pont, who is in her 80s, spread out the bands needed to contain the claws of the lobster they hope to catch. Jessica Rinaldi/The Boston Globe

“I’m just banding lobster and measuring them,” said Pont, 81. “And there’s not a lot of that.”

Grimshaw, who comes from a family of fishermen and began lobstering as a teenager in Stonington, says he will keep at it as long as he can, even if he’s not making money.

Nearly all he earns now goes toward paying his 25-year-old son, Roddy, and covering the costs for bait, fuel, and maintaining his boat, the Lady Lynn, a 48-year-old Bruno Stillman named for his first ex-wife.

It’s considered bad luck to change the name of a fishing boat, he said, so he kept it.

When asked why he never switched to another fishery, he said it would have been too expensive. Plus, he prefers the lifestyle of lobstering. “You get to sleep in your own bed,” he said.

Roderick Grimshaw, Judy Pont, and Ronald Pray pulled traps aboard the Lady Lynn. Jessica Rinaldi/The Boston Globe

Fellow fishermen and others who know Grimshaw remain in awe that he has kept fishing all these years, when so many others were forced to find other ways to make a living.

Gary Farrell, the dock master of Stonington Fishermen’s Dock, recalls the good days and described Grimshaw as “a real go-getter.”

“Personally, I don’t see how he keeps going,” Farrell said. “It’s really tough out there, but your heart goes out to the guy for not giving up.”

Rob Smith spent the heydays as Grimshaw’s sternman before starting to fish on his own. He kept at it for years, but eventually he had to find another job to make ends meet. While he still fishes on the side, he now earns a living as a machine operator in a quarry.

“I was proud of what I did, and I loved it,” he said. “It’s just sad what happened. We did really well back in the day, but the industry couldn’t support us anymore.”

After a few hours at sea, in which he hauled 10 trawls, Grimshaw was shaking his head as he navigated back to the dock.

They brought back just 25 lobsters, many of them barely big enough to keep. Of those, nine were considered “cull,” meaning they lacked claws or were otherwise damaged.

“Piss-poor,” Grimshaw called the catch. “It does something to your ego.”

It wouldn’t be enough to break even on the trip, even with the price of lobster high. Still, he remained optimistic, looking ahead.

“I’m not going to let it stop me,” he said. “I’m just going to keep doing what I’m doing.”

Michael Grimshaw made his way up the ladder after a disappointing day of hauling traps. Jessica Rinaldi/The Boston Globe