Westslope Cutthroat Restoration Shows Good Results

By Beacon Staff

A decade-long program to restore Montana’s state fish to a chain of 21 alpine lakes above the South Fork Flathead River drainage is showing good results, a Montana Fish, Wildlife and Parks official said.

Some of the lakes in the Westslope Cutthroat Trout Conservation project have been poisoned to kill non-native fish and then stocked with cutthroats. Others have been densely stocked each year with genetically pure trout to try to get rid of hybrid populations. Five remote lakes have received no treatment so far.

“We are beyond the halfway point and the really exciting part now is that we are seeing the fruits of our labors,” project leader Matt Boyer said. “Anglers are catching fish, we are seeing natural reproduction and the lakes are being restored back to genetic purity.”

Some people originally against the project have changed their minds as the program enters its sixth year, Boyer said.

“We have a number of people who, while staunchly opposed to this project initially, have now become some of our biggest supporters,” Boyer said.

Jim Vashro, a regional fisheries manager, said that the project has the potential to be self-sustaining. The restoration program is being paid for by the Bonneville Power Administration.

“It would be ideal if we could walk away from those lakes and let the fish run this themselves,” Vashro said.

Officials say westslope cutthroat trout occur in just 9 percent of their historic range following decades of habitat loss and interbreeding with non-native trout such as rainbow and Yellowstone cutthroats.

The project started in 2007 amid concerns that hybridized fish populations would make it into the South Fork drainage and increase the numbers there. The South Fork Flathead represents 50 percent of westslope cutthroat range.

The goal of the project is to wipe out hybridized trout in the watershed by about 2017. That involves stocking pure genetic strains of the fish, which are being raised at the Washoe Park Hatchery in Anaconda. Brood stock for the program came from the Clark Fork River and South Fork of the Flathead, home of the purest westslope cutthroat populations in the state, Boyer said.

Biologists have also taken brood stock from a genetically pure cutthroat population from Danaher Creek in the Bob Marshal Wilderness. Those fish were spawned for the first time last year, and biologists plan to plant the offspring in the Necklace Lakes chain.

“The simple thing to do would be to put the state broodstock fish everywhere, but the downside is that you homogenize all the diverse populations in the South Fork by planting broodstock from a genetically identical stock,” Boyer said. “A better approach from a conservation standpoint is to achieve genetic variation by using multiple sources.”

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