Trout project targets upper Big Salmon Creek

Delayed by wildfires in the Bob Marshall Wilderness, biologists this week will continue an effort to rid the South Fork of the Flathead River drainage from non-native trout.

The South Fork is considered one of the last bastions for pure westslope cutthroat trout in the U.S.

Over the course of the past eight years, biologists from Montana Fish, Wildlife and Parks have been treating lakes in the Bob Marshall Wilderness and near the Hungry Horse Reservoir with rotenone, a quick-acting poison that kills fish and then breaks down when exposed to environmental factors, like sunlight.

This year's project will treat a three-mile section of Big Salmon Creek upstream from its confluence of Albino and Tango Creeks. The project will not impact Big Salmon Lake, said FWP fisheries biologist Matt Boyer. The original plan was to treat the stream the week of Sept. 7, but wildfires near Lena Lake forced a delay. The fires have since simmered down.

FWP in recent years has already treated lakes upstream from the creek, including Lena Lake and the Necklace Chain of Lakes. The non-native fish, which include rainbow and rainbow-cutthroat crosses, exist in the creek now, Boyer noted. They migrated downstream from the lakes.

Biologists will hike to a camp about 16 miles from Holland Lake and were expected to start the treatment Tuesday and be done by Sunday.

During the effort, portions of Big Salmon Creek Trail No. 110, Albino Creek Trail No.118, and Smoky Creek Trail No. 120 were closed through Wednesday.

Boyer said most of the dead fish sink to the bottom of the stream. He said in past projects, they have not resulted in increased bear activity.

FWP will then go back and restock the stream with native cutthroat trout that have been reared from South Fork stock in a local hatchery.

Boyer said that after about two years, lakes that have been previously treated are fishing well, with anglers reporting fish in the 15- to 16-inch range.

"Fishing in these lakes has been good," he said.

Next year the project will treat Handkerchief Lake on the west side of the Hungry Horse Reservoir. It will be restocked with Red Rock grayling and westslope cutthroats.

The project is expected to wrap up in 2017 with the treatment of Sunburst Lake, the largest lake in the project's scope. Sunburst is a wilderness lake in the northwest corner of the Bob Marshall Wilderness.