Authorities said Thursday they have no clue where a Long Island man who hasn’t been seen since the weekend might have gone, or why he is missing.

Dana L. Moy, 31, “left us with nothing really to go on,” said Lt. Don Foss of the Cumberland County Sheriff’s Office.

Moy left behind a note that suggested he might harm himself, Foss said, but there was no indication of what he might do or where he would go.

“I guess we’ll call it a suicide note,” Foss said, although Moy did not say directly that he planned to kill himself. The note, Foss said, told friends and family that they wouldn’t find him alive and “there were some innuendos … (that suicide) seemed to be what he was going to do,” although there was no specific declaration.

Foss said Moy was last seen either Saturday or Sunday on Long Island – witnesses who saw him riding his bicycle weren’t sure which day. The bike was found in the grass near the marina where Moy kept his boat, a 2005 Carolina Skiff, which is 17 feet long, equipped with a 70 hp outboard and named “Low Expectations.”

The skiff is missing, and Foss said authorities don’t know how long it has been gone.

Moy also left behind his cellphone, Foss said, limiting the technological tools authorities might use to find him. Sheriff’s deputies searched Long Island, where Moy lives year-round, on Wednesday.

Foss said friends and family told the sheriff’s office they don’t know of any physical or mental problems that might have led him to leave.

Moy was introverted, Foss said, “but the people we’ve talked to are surprised by this.”

Bill McCalmon, who owns the Long Island Store, said he’s known Moy for 15 years.

His disappearance “is devastating to the island because he was one of us,” McCalmon said. The island has only about 250 year-round residents, although the island population usually triples in the summer.

Moy often worked as a sternman for island lobstermen, McCalmon said, but he didn’t know if he had been working with any of them recently. Moy came into his store occasionally, McCalmon said, but hasn’t been in as often this year as in the past.

He said Moy’s mother died less than two years ago, and the loss seemed to affect Moy greatly.

But “I would not have guessed that this was possible,” he said.

The Maine Marine Patrol sent a plane over the island Wednesday and Thursday, said Jeff Nichols, a spokesman for the agency. But Nichols said the flights were added on to normal patrols and were flyovers, rather than the pilot following a precise search pattern.

Likewise, the Coast Guard said it doesn’t have enough information to set up a search, although those officials on patrol Wednesday and Thursday have been asked to keep an eye out for Moy’s small craft.

“We have no information to really go on,” said Coast Guard Lt. David Bourbeau, explaining why they aren’t formally searching for Moy.

Coast Guard ships on routine patrols have been asked to keep an eye out for Moy, Bourbeau said.

Foss said boaters, fishermen and harbormasters have also been asked to be on the lookout for Moy.

Moy is white, 5 feet, 10 inches tall and weighs about 185 pounds. He has brown hair and blue eyes. Anyone with information is asked to call the sheriff’s office at 774-1444, extension 2215.