After spending two months catching and marking 267 big brook trout in 11,000-acre Chamberlain Lake, researchers Stephen Seeback and Jason Seyfried are hoping they don’t see many of them in the pails of ice fishermen when they check on anglers on the lake this winter.

Few sightings of marked fish this winter would suggest there are many more brook trout in the lake than there seemed to be after the first stage of their study. It is being conducted to determine whether brook trout are being overexploited on Chamberlain, one of the premier places to catch Maine’s most popular game fish.

“Either there are trout there and we didn’t get them, or there is a concern with the population,” Seyfried said.

While the fishing didn’t go well despite exhaustive efforts, regional state biologist Paul Johnson, who is overseeing the study for the Department of Inland Fisheries and Wildlife, said the low catch rate may not necessarily translate into bad news for Chamberlain – not if the large size of the fish caught offers an accurate profile of the population.

“If we see 300 and 100 are marked, that would be 30 percent of the fishery. But obviously the lake is able to sustain them because there still are big fish there,” Johnson said. “[Those big fish] would be the first ones to go. So it may not all be doom and gloom.”

Chamberlain Lake has remained something of a mystery to biologists. In fact, little is known about brook trout in most big lakes in Maine.

DIF&W biologist Johnson said research on brook trout has been confined to small ponds less than 200 acres in size, ponds which constitute only 10 percent of waters that support brook trout fisheries.

On lakes more than 200 acres in size, where most of Maine’s brook trout are found, there have been just three studies. All were done by DIF&W biologist David Basley on Eagle Lake.

In the Chamberlain study, the goal was to catch 500 fish more than 12 inches in length. That assumed there were 2,200 mature brook trout in the lake, which would have been consistent with what Basley has found in Eagle Lake.

Basley and his crew, however, caught 475 of the big brook trout this fall on a lake 150-acres smaller than Chamberlain, where Seeback and Seyfried caught only 267.

“We’re managing what could be a very fragile resource,” Johnson said.

At the same time, the study on Chamberlain Lake has shown already that the brook trout there are mostly large, healthy fish.

“This is a good fishery,” Seebeck told a room of state fisheries biologists Monday at their biannual meeting in Waterville, where he and Seyfried presented their findings.

Of the total 350 fish they caught, 76 percent were over 12 inches, the legal length for fishermen to keep, and 14 percent were over 18 inches.

Just how many fish are in Chamberlain Lake won’t be known until Seebeck and Seyfried do a ground survey of anglers during ice fishing season.

The two researchers will see what percentage of those fish caught this winter have a clipped fin marking, and they will estimate the population from that information.

Basley said the brook trout in Eagle Lake appear to be more abundant, but they also are much smaller on average, although they have been getting bigger.

Basley reported Monday that the numbers of brookies 12 inches or greater has been growing in the past 10 years. He surmised this was due to the 1996 regulation that allowed only one fish caught in the daily bag limit to be 14 inches or larger.

In 1991, Basely said, 53 percent of the brook trout in Eagle Lake were 12 inches or greater, in 1996 that increased to 59 percent, and this fall he said as many as 79 percent of the population was that big.

While Eagle Lake seems to have more brook trout, those that Basley and his assistant biologists have handled are not as impressive as the ones in Chamberlain.

On Eagle, the average length caught this fall was 13.5 inches, compared to 14.2 on Chamberlain. And Basley found just two brook trout out of 475 that were 18 inches or larger, while 14 percent of the total of 350 caught on Chamberlain were that big.

Johnson said if there are fewer brookies in Chamberlain, it could be because of the fact the lake has more fishing pressure. Unlike Eagle, Chamberlain has a logging road leading up to it and motor boats of all sizes are allowed on it.

“[Eagle] only has canoes with small motors. In Chamberlain, the sky’s the limit. You can use the Queen Mary in there,” Johnson said.

Deirdre Fleming covers outdoor sports and recreation for the NEWS. She can be reached at 990-8250 or at dfleming@bangordailynews.net.