The University of Montana’s Flathead Lake Biological Station will study how tribal efforts to suppress non-native lake trout populations are possibly shifting the buildup of toxins in other fish species. The project is part of an inaugural wave of federal funding announced Wednesday for projects along the Columbia River Basin.
The Confederated Salish and Kootenai Tribes have been working for years to reduce lake trout populations by 75 percent in Flathead Lake, with the goal of restoring other fish species.
The Flathead Biological Station is getting $128,000 from the federal Environmental Protection Agency to study what that removal of lake trout means for the buildup methylmercury in other fish.
Methylmercury is a poisonous mercury compound created when mercury is dissolved into freshwater and seawater. It can build up in fish and eventually travel to humans who eat them, potentially causing health impacts.
Nannette Nelson is a natural resources economist with the Flathead Lake Bio Station.
"Lake trout are a fairly long-lived species, and for that reason they can actually accumulate quite a bit of methylmercury, to levels that are not healthy for individuals to consume."
Nelson explains that lake trout are a top predator, and because the toxin works its way up the food chain, that typically means lake trout harbor higher levels of methylmercury. If lake trout are taken out of the food chain, other predators could accumulate more of the toxin.
Nelson says the new project will also examine whether lake trout fillets made available to local food pantries are improving low-income families’ diets. The Bio Station will share its findings with the tribes sometime next year.
The project was one of 14 grants, totaling $2 million, from the U.S. Environmental Protection Agency announced this week. The grants are aimed at improving water quality throughout the Columbia River Basin.