By Cindy Sandoval, USFWS
Idaho Fish and Game (IDFG), in an act of both conservation and ecological insurance, is relocating fisher into the forests of the Coeur d’Alene Mountains. Here, among the mountain forests and dense underbrush biologists hope to boost the state’s fisher population. This work, supported in part by Pittman-Robertson funding from federal excise taxes paid by manufacturers of firearms, ammunition, and select archery equipment, reflects both active conservation efforts and long-term ecological planning.
This translocation of eleven fishers builds on decades of work to restore the species across the state. By moving animals into suitable but currently underoccupied habitat, managers are helping them bypass obstacles such as highways and wide rivers that can isolate populations and slow natural dispersal. The effort is designed to increase genetic diversity while also reducing the species’ vulnerability to emerging threats, including larger and more frequent wildfires.
Fishers are agile, forest-dwelling carnivores. By preying on species like snowshoe hares, squirrels, and porcupines, they help maintain balance in forest ecosystems. Once widespread across the West, fishers declined due to habitat loss, the poisoning of large carnivores, and unregulated trapping. Beginning in the 1950s, biologists introduced fishers from British Columbia and the Midwest into Idaho and western Montana. Today, the descendants of those animals, along with Idaho’s remaining native fishers, form the state’s current fisher population.
Long-term monitoring and genetic studies show that most of Idaho’s fishers exist in two separate groups: one in the Cabinet Mountains and another in the Nez Perce–Clearwater National Forest region. Between them lies the Coeur d’Alene Mountains, an area with abundant but underused fisher habitat, making it a natural choice to boost fisher population and range.
The Coeur d’Alene Mountains
The Coeur d’Alene Mountains, part of the Bitterroot Range, offer a diverse mosaic of forest types, including extensive forest stands ideal for fishers. These carnivores adjust their movements seasonally, tracking prey through changing forest conditions. The Coeur d’Alene Mountains’ varied terrain and vegetation provide exactly the complex environment fishers need to thrive.
In December, biologists partnered with local trappers to capture 11 fishers from a healthy population in the Nez Perce–Clearwater National Forest. The animals were carefully handled, fitted with radio collars, and transported to release sites in the Coeur d’Alene Mountains. “Working with trappers is beneficial,” said IDFG biologist Cory Mosby, who coordinates the department’s fisher augmentation efforts. “They spend time on the landscape year-round, understand the terrain, and recognize signs of fisher presence. Their expertise allows us to capture healthy animals while minimizing stress.”
Through each fisher’s new radio collar, biologists can monitor survival, habitat use, and denning behavior. Early tracking results are encouraging, and additional translocation efforts are already being planned to further support recolonization. “Our initial efforts this winter have been quite successful and survival has been high. With this good news, we plan to conduct a second year of augmentations of 10-20 fisher into the Coeur d’Alene Mountains from our capture sites used last year,” adds Mosby.
Planning for a Changing Future
These 11 fishers mark the latest step in a long-term strategy to improve connectivity between isolated populations establishing a third viable group in the Coeur d’Alene Mountains. Strengthening these connections helps maintain genetic diversity and resilience across Idaho’s fisher.
At the same time, the effort anticipates growing challenges. Wildfires in Idaho and across the West have become more frequent and severe. Expanding the number and distribution of fishers creates a buffer ensuring that if one population is affected, others may persist.
As these animals settle, reproduce, and disperse, they represent more than just a population boost. Each fisher represents an opportunity to establish territory, produce young, and contribute to a broader recovery story. What may seem like a small number is, in reality, a meaningful step to continue long-term stability for a species once nearly lost in Idaho.
Adding to a Nationwide Effort
Across the country, other state fish and wildlife agencies have worked to reintroduce and actively manage fisher. In the Northeast, state fish and wildlife agencies are focusing on species monitoring, habitat management, and public education to support fisher populations. Fishers were reintroduced to Connecticut in the 1980s. Today, the Connecticut Department of Energy and Environmental Protection is conducting a research project to better understand fisher mortality and population trends. As part of this study, fishers are fitted with collars to track their movements, habitat use, and survival. In Rhode Island, over 50 fisher have been collared and multiple trail cameras have been deployed to track and collect data on the state’s fisher population. Together, these efforts show how sustained investment through Pittman-Robertson funding supports not only active translocation, like those in Idaho, but sustains ongoing research and management that enable species like the fisher to reestablish themselves in diverse landscapes across the country.