There are dozens of big, shimmering red masses that bob up and down on the Vineyard Haven side of the Lagoon. None of them are supposed to be boats.

“They thought it was a buoy or maybe a dinghy that had turned over,” Tisbury harbor master John Crocker said Friday. “It wasn’t that.”

On Wednesday, the owner of MV Dock and Float Rick Waldron and a diver salvaged an approximately 20-foot, red-bottomed center console vessel that had sunk and turtled in the Lagoon Pond mooring field by the Beach Road access point, pulling the boat out of the water with equal parts barge, winch and spirit of will.

Not a buoy. — Kurt Freund

The boat had sunk earlier in the morning, turning upside down on its mooring before Tisbury shellfish constable Danielle Ewart noticed the waterlogged vessel. She alerted Mr. Crocker, who happened to see Mr. Waldron on the pond with his barge. Mr. Waldron agreed to perform the rescue.

With the help of his diver, Mike Wilson, the pair were able to hook up straps to the boat with a barge winch and undo it from the mooring. They then flipped the vessel and pumped out the water.

“Every rescue is a bit different, but on this particular occasion the guy forgot to put the drain plug in it,” Mr. Waldron said.

In fact, the boat — a 22-foot Sea Ox with a Mercury outboard, according to Mr. Waldron — had just been launched earlier Wednesday morning.

“It was an unfortunate circumstance,” Mr. Crocker said. “The guy launches his boat. He’s going to have a great summer. And then it’s ruined.”

He confirmed the owner of the boat is Marc Petricone.

But the rescue Wednesday may have saved the boat — and the owner’s summer. Even more miraculously, the Mercury outboard was running after the submersion as well.

“It all went good,” Mr. Waldron said. “The boat was upside down. We rolled her back upright, and got her out. And we got the engine running too, which took a few hours.”

“There’s not a lot to it with these small boats,” he added.

Mr. Crocker said there was no fuel leak in the pond, either.

“The first thing I looked for was a sheen on the water, and there was no sheen, so that was good,” Mr. Crocker said.

Mr. Crocker said there would be no law enforcement investigation into the sunken vessel.

Boat salvages are relatively rare, with Mr. Waldron estimating that he had only performed two or three rescues since 2018. But mistakes like forgetting a drain plug mark the start of summer in Lagoon Pond, which the harbormaster predicted would bring more than its traditional share of bizarre, unpredictable and unforeseen business this season.

For the moment, Mr. Waldron and Mr. Crocker just hoped that buoys were the only red, shimmering masses bobbing around in the water.

“It was a mistake, and the guy kicked himself in the butt,” Mr. Waldron said. “But it all worked out.”