NORWAY – Thirty anglers from Rangeley to Naples attended Wednesday night’s meeting of the Mollyockett Chapter of Trout Unlimited.

Chapter officials said the record crowd was attracted by the night’s topic – Rapid River brook trout studies to reduce illegally stocked bass in the river – and presenter Bill Hanson of Lewiston.

Hanson is the senior biologist for Florida Power and Light Co., a subsidiary of the FPL Group which acquired most of Central Maine Power’s hydropower-generating plants in 1999.

Working on the Rapid River in conjunction with fisheries biologists from the Maine Department of Inland Fisheries and Wildlife, and U.S. Fish and Wildlife, Hanson has been conducting radio tracking studies of brook trout, salmon and bass.

By catching and surgically inserting radio transmitters set to differing frequencies in the bellies of fish, Hanson and other biologists have been able to track bass and the two salmonid species in the first two years of a three-year study.

“The nice thing about radio telemetry is that it takes all of the guesswork out of it,” Hanson said.

After literally bugging the fish with small devices to which are attached a length of antenna wire that hangs outside the fish, biologists have been able to track their seasonal movements in upper Androscoggin River watershed waters.

Telemetry data also helps biologists understand the spawning habits of brook trout, salmon and bass, which was illegally stocked in 7,850-acre Lake Umbagog several years ago.

He said researchers learned that Pond in the River is an important part of the Rapid River’s section – its cool, clean and fast water acts like a rest stop for brookies.

That’s one reason why the Rapid River, which flows through Upton and Magalloway Plantation between Lake Umbagog and Middle Dam on Lower Richardson Lake, has been a prized brook trout fishery for many years, Hanson said.

That is, until the illegal introduction of the bass, which threw a monkey wrench into the hydropower company’s attempts to alter flows from Middle Dam in hopes of creating better habitat for brook trout.

“They skewed us up, because it potentially blows away anything we try to do with flows. It’s been a little bit crazy,” Hanson said.

Bass and brook trout do not coexist well together.

“The brook trout must share its space with a pretty aggressive fish. Bass can just overwhelm salmonids. They produce thousands of young each year. They’re like mosquitoes,” he said.

Salmon, which Hanson pegged as an equal competitor of bass, tend to aggravate the situation. All three compete for the same amount of food.

However, salmon also compete with trout for spawning sites. Hanson said that salmon will essentially “rototill” a site that a brook trout has readied for egg deposits, forcing the trout to look elsewhere.

“Bass can stand a lot less oxygen in the water than trout, and they can handle any flows we can throw at them. But it’s ironic that bass are getting the wrong name, because they’re the new exotic,” he added.

The Rapid River never had salmon in it until they were stocked there many years ago.

“But our studies have shown that there are definitely big, beautiful brook trout in the river, and they’re doing just fine now,” Hanson said.

Only time will tell what the bass inoculation will do to the river’s prized trout fishery.

“We’ve pretty much accepted that they’re there to stay. We haven’t found any magic solutions to the bass problem, but what we have learned will help us manage it to the best potential.

“It’s not the gloom-and-doom you hear nowadays that all brook trout will go away tomorrow,” Hanson added.

tkarkos@sunjournal.com

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