Danger Ahead for Idaho’s Bull Trout

This year has been a big one for news regarding public lands and wildlife. In late 2024, the U.S. Fish & Wildlife Service (USFWS) added to the list with the release of a significant report on bull trout: the 25-year species status review of bull trout populations since the species was listed at “threatened” under the Endangered Species Act in 1999.The 538-page Species Status Assessment (SSA) and associated summary provided a progress update on the agency’s 2015 Recovery Plan. It assessed bull trout abundance in 118 Core Areas designated as Critical Habitat in five states—Washington, Oregon, Montana, Idaho, and a tiny slice of Nevada.Recovery plans for ESA-listed species provide guidance to fish and wildlife managers on ways to avoid or minimize threats and to track whether populations are recovering. For bull trout, recovered populations would 1) be well dispersed across representative habitats, 2) retain genetic diversity and migratory characteristics, and 3) have access to connected, cold-water habitats.Bull trout use three life-history strategies in many Idaho streams: fluvial (living in rivers, but spawning in fairly small tributaries); adfluvial (living in lakes and spawning in rivers); and non-migratory (living year-round in small streams and headwater tributaries). Bull trout also need specific habitat conditions that support these strategies. Biologists call these “the four Cs”: cold, clean, complex, and connected habitat. This means cold, pristine water, streamside cover, stable river channels for spawning and rearing, and intact river corridors that allow seasonal migration. The USFWS identified threats to the “four Cs” that support bull trout: fragmented waterways, nonnative species such as brook trout, water quality impacts from climate change, and road construction. Also important is that, compared to other trout species that spawn in the spring, fall-spawning bull trout have a long incubation cycle as waters cool. This makes their eggs especially vulnerable to sediment and poor water quality.The takeaway news from the status assessment was that the USFWS did not change the listing status of bull trout. The fish will continue to be designated as “threatened”. However, the agency concluded that “the bull trout remains likely to become in danger of extinction in the foreseeable future throughout its range.” The analysis looked at current bull trout abundance and distribution in areas of Critical Habitat and modeled trends over the next 60 years, as effects of climate change continue to increase. For many parts of Idaho, the results were encouraging. The model showed many Core Areas in Idaho had the best potential for resilient bull trout populations in the lower 48. Two of these watersheds included headwaters streams like the Upper South Fork Salmon River (SFSR) and Arrowrock Reservoir. SFSR populations had the highest overall resiliency score of all 118 areas characterized. The USFWS has designated Critical Habitat for bull trout throughout the South Fork Salmon River watershed, including the East Fork SFSR, and in Burntlog, Cane, Cinnabar, Meadow, Tamarack, Trapper, Riordan, and Sugar creeks. The East Fork SFSR watershed alone has almost 20 miles of bull trout habitat. They currently use spawning and rearing habitat in at least 28 streams within this subbasin. However, while the two small, local populations of bull trout in the SFSR and Arrowrock Reservoir are currently regarded as healthy, their future is uncertain. Unfortunately, both are threatened by two of the biggest mining proposals in Idaho—the Stibnite Gold and CuMo projects.The Stibnite Gold Project, advanced by Perpetua Resources, currently includes plans for construction of a 38-mile industrial haul road through the middle of the East Fork SFSR—some of the most rugged and remote backcountry in Idaho. The proposed Burnt Log Route will widen 23 miles of a lightly used Forest Service Road to roughly four times the current width and add another 15 miles of new road through Inventoried Roadless Areas immediately adjacent to the Frank Church-River of No Return Wilderness. At least one section will reach over 8500 feet in elevation.Annual operations of the Stibnite Gold Project (SGP) would rely on the Burnt Log Route to transport large quantities of fuel, chemicals, and supplies. This includes 6.3 million gallons of diesel and gasoline, 100 tons of explosives, and 4,000 tons of sodium cyanide, among dozens of other “hazardous materials.”Over 70 water crossings would be required for access roads to SGP, many spanning fish-bearing streams and waterbodies. The USFS’ 2022 Aquatic and Fisheries Report for Stibnite Gold Project stated, “there is the potential for spills to occur along access roads as fuel and other materials are trucked to and from the SGP…the proximity of the access roads to surface water resources increases the potential for a release to enter water which could result in major consequences.”Due to spill risk and a host of other aquatic threats, the Forest Service’s Biological Assessment determined, in 2024, that SGP was likely to adversely affect bull trout, Chinook salmon, steelhead, and their critical habitat. The agency also concluded that the effects of the project on bull trout would be major and permanent.The USFWS concurred, stating that dozens of SGP actions would harm bull trout by “causing or contributing to: physical passage barriers; sediment and turbidity pollution; the risk of hazardous material spills; chemical contamination; increased water temperatures; and streamflow depletions”.The proposed Burnt Log Route would be the source of much of this harm. Ironically, a Perpetua press release once claimed, “Perpetua also has proposed using Burntlog Road in order to keep vehicles away from precious waterways.”In mid-September, ICL staff will traverse sections of the proposed industrial highway to gain a firsthand look at the scale of this project and its risks. We hope to bring home tales from the fringes of the most remote lands in the lower 48, and a sobering glimpse into what may be coming to bull trout country. We’ll take you there with videos and photos, celebrating the resilience that species like bull trout and wolverine still display there in Idaho’s wild country.Stay tuned. We’re going to tell you all about it.