State wildlife officials announced a $6,000 reward for information leading to the arrest and conviction of those responsible for illegally introducing largemouth bass into a Down East lake.

Biologists confirmed last week the presence of largemouth bass in West Musquash Lake, the Maine Department of Inland Fisheries and Wildlife said in a statement Thursday. West Musquash is in Washington County about 8 miles southwest of Topsfield.

“The team of biologists from across the state caught and visually confirmed multiple largemouth bass of varying ages in the lake,” the statement says. “Biologists also confirmed there were no largemouth bass in Orie Lake, which feeds into West Musquash, and natural barriers prevent upstream passage of bass into West Musquash, indicating the bass were moved illegally into West Musquash.”

West Musquash covers about 1,600 acres and has no lakeside development aside from four small camps and boat access, the department said.

“West Musquash is a deep, clear, cold-water lake that is truly special to the region and area,” said Jacob Scoville, the department’s regional fisheries biologist. “The lake supports a wild brook trout, wild lake trout and wild landlocked salmon fishery, and also is one of the last waters in the state with a population of round whitefish. This is the only water in the region that has all these fisheries without an active stocking program.

“Sadly, this introduction will no doubt change the lake forever.”

Maine’s Operation Game Thief, a nonprofit organization, has pledged $5,000 toward the reward, while the Grand Lake Stream Guides Association has contributed $1,000.

Anyone with information regarding the illegal introduction of largemouth bass into West Musquash Lake is encouraged to contact Operation Game Thief at 800-253-7887. Tips can also be submitted online by visiting their website, maineogt.org.