When Andrew Todd went out on Feb. 18 to haul his lobster traps, he could tell right away that something was wrong.

By the time he was done checking all his traps, he determined that 100 of them had been illegally hauled and emptied.

“Whoever did it didn’t even bother to close the trap door to make it look like nothing was wrong,” Todd, 59, of Chebeague Island, said Friday.

Todd was one of three lobstermen who reported to officials that their traps had been tampered with last week. The Maine Marine Patrol began an investigation and found that at least 200 traps were illegally hauled in an area of the Gulf of Maine known as Jeffreys Ledge, a productive fishing and lobstering ground about 30 miles off the coast of New Hampshire.

On Friday, Maine Operation Game Thief, a private, nonprofit organization that works with the Maine Department of Marine Resources, the Marine Patrol, the Department of Inland Fisheries and Wildlife, the Maine Warden Service and Wildlife Crime Stoppers, offered a reward of $11,000 for information that helps authorities find the thief or thieves. The reward money comes from a variety of sources, including people in the lobster industry. Todd put up $1,000 of the reward money himself.

The traps were all hauled by someone other than the traps’ license holders, according to theDepartment of Marine Resources. In all cases, lobsters were removed and the empty traps were then lowered back to the ocean bottom, although some traps were not retrievable.

“This happens from time to time, but never on this scale,” said Todd, who grew up in a fishing family and has been lobstering his entire adult life.

“Five or six years ago, this didn’t happen,” he said. “But we’ve got a new cast of characters now. I think there is the same percentage of crooks among lobstermen as anything else.”

Maine Marine Patrol Col. Jon Cornish called the case an “extremely serious violation,” and appealed to the public for help. That’s where Operation Game Thief comes in.

“The (Operation Game Thief) program is committed to helping maintain our state’s valuable game and commercial fishing resources,” Greg Sirpis, the organization’s chairman, said in a statement. “Maine’s lobster industry works hard to protect and sustain this important resource, and to have people undermine our state’s proud heritage of hard work and conservation is unacceptable and we will support efforts to bring whoever did this to justice,”

The lobster-laden waters off Maine’s coast are subject to relatively minimal oversight and, historically, lobstermen settle disputes among each other, sometimes with violence or threats of violence. Maine Marine Patrol spokesman Jeff Nichols said it’s not uncommon to get complaints of lobster trap molestation, especially considering the state has more than 5,500 license holders. But Nichols said the scale of the most recent case is certainly unusual.

Molesting lobster gear, which can mean hauling traps illegally or otherwise tampering with them, is a civil violation, punishable by a fine of up to $500. However, if the person or people responsible are also license holders, they risk losing that license for a mandatory three-year period.

Todd, who has a total of 780 traps, is convinced that whoever tampered with his traps is also a lobsterman and he guessed that it was probably more than one person.

“No one goes out there alone,” he said.

Anyone with information on the case is encouraged to contact Marine Patrol Sgt. Rob Beal at 479-3931 or to call the Operation Game Thief hotline at 1-800-ALERT-US (1-800-253-7887).

Todd said even if the reward doesn’t lead to a resolution, he hopes the publicity puts people on notice.

“We’re pretty fed up out there,” he said. “I hope this serves as a deterrent.”