Are Walleye Welcome in Noxon Reservoir?

By Beacon Staff

Sitting in a forested river corridor near the northwest border of Idaho, Noxon Rapids Reservoir spans 30 miles of prized water along Montana Highway 200.

The narrow reservoir north of Thompson Falls is one of the most popular recreational lakes for anglers in the state.

It’s also the source of an unprecedented and contentious quandary for anglers and state managers.

In the ongoing struggle over how to manage nonnative fish populations, Montana Fish, Wildlife and Parks is back at the drawing board after receiving a flood of opposition to its proposed study of suppressing illegally introduced walleye in Noxon Reservoir.

The state agency announced in spring its intent to investigate intensified electrofishing and/or gillnetting of walleye in the upper portion of Noxon Reservoir for the next six years.

The proposal sparked 431 comments during the extended public scoping period, 359 of which were in opposition, plus three form letters and seven petitions.

According to FWP, the issues raised from public comment included the potential bycatch of non-target species during suppression efforts, funding availability, removal techniques and the economic impacts of both allowing walleye to establish in the lower Clark Fork and the consequences of removal efforts.

In response to public outcry, FWP announced on July 30 that it would revise the draft environmental assessment that detailed the six-year suppression effort to reexamine issues brought up during the scoping process, but also to gather more detailed information for the public about why walleye pose a threat to a beloved fishery.

“Despite a majority in opposition to this project, I believe we are compelled to consider suppression efforts based on threats posed to established fisheries, including native westslope cutthroat and bull trout, and potential impacts to the ongoing multi-agency Native Salmonid Restoration Plan in the Lower Clark Fork drainage,” FWP Regional Supervisor Jim Satterfield wrote in his EA revision notice.

On a per-acre basis, Noxon Reservoir experiences nearly the same angling pressure as the most popular lake in Montana, Canyon Ferry Reservoir in Helena, according to FWP.

It’s not surprising. The scenic body of water behind Noxon Dam is home to some of the best bass and pike fishing in the state.

The reservoir tempts anglers from all over to pursue the abundant populations of largemouth and smallmouth bass and northern pike, along with brown, bull and rainbow trout, lake and mountain whitefish and more. In 2009, an angler in Noxon Rapids landed the state record largemouth bass, 22.5 inches long and weighing 8.8 pounds. Nearly 10 fishing tournaments take place on the reservoir every year, filled with fishermen dreaming of a similar catch of a lifetime.

“What we have here is really great,” said Kenneth Breidinger, an FWP fisheries biologist based at Noxon Reservoir.

Yet the reservoir is also home to a strong walleye population.

Walleye are beloved among many anglers. They give a good fight when hooked and are known for being one of the more tasty catches.

But the fish are also a voracious predator that can spawn rapidly and assault other fish populations, especially those in younger stages of development.

A walleye caught by Montana Fish, Wildlife and Parks biologists on Noxon Reservoir. – Photo courtesy FWP

“We have a lot of literature and case histories, and a lot of local research completed, that suggests walleye could be very detrimental to our fisheries here,” Breidinger said. “What we have is working and walleye are definitely a pretty big threat to that.”

The sport fish became an increasingly popular catch in the eastern part of the state in the 1970s and 1980s, and has since migrated west. State managers discovered the fish was illegally introduced in Noxon in the 1980s.

In 1989, FWP launched an environmental assessment of the introduction of walleye across Montana, led by Peter Colby and Chris Hunter. The researchers set out to get a handle on walleye species and explore the impacts of the fish expanding beyond its current range.

“The potential exists for walleye to negatively affect existing trout, yellow perch and kokanee fisheries through predation,” the pair wrote in their study. “This potential has resulted in fish and game agencies in other western states taking a firm stand for no introductions of walleye into salmonid waters.”

FWP determined that lakes on the east side of the state were appropriate habitats for walleye, and could be restocked regularly. But the fish would be considered an outlaw in the west. Per policy, walleye were not to be accepted or established west of the Continental Divide.

Those policies provide the agency with discretion to evaluate the feasibility of control projects, according to FWP, which is the purpose of the upcoming environmental assessment.

Fish biologists at Noxon have tracked the population over the past two decades and documented the successful reproduction in 2000. Biologists began netting and electrofishing walleye in Noxon in the spring of 2012 as a way to monitor the fishery and determine the population size.

By tagging and tracking the fish species, FWP said it became apparent that walleye had a growing stronghold in Noxon.

“We were pretty concerned about the numbers that we were seeing,” Breidinger said. “We had a couple of years where it looked like walleye were really starting to expand more rapidly. We started trying to consider suppression efforts.

“They have the ability to exceed carrying capacity very quickly,” he added.

Walleye suppression is unprecedented in western Montana, but it has been a brewing battle ever since the sport fish were illegally introduced.

“It’s a controversial project and something a lot of people feel very strongly about. There are a lot of people trying to drum up support for their side on both sides,” Breidinger said. “That’s a good thing, that a lot of people care about the fishery and care about where it’s headed.”

For more information about FWP’s proposed walleye management, visit fwp.mt.gov/news/publicNotices/decisionNotices/pn_0654.html

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