One of the rarest mammals in the continental US, numbering less than 300 animals, the wolverine is found predominately in Idaho and Montana. Processing one of the lowest recorded reproductive rates in North American mammals, wolverine females typically reproduce in their 2nd or 3rd year and then on average only every other year, with characteristically very small litter sizes of 1-2 kits. Tightly linked and believed dependent upon high elevation areas where snow remains well into spring, wolverines exclusively use snow dens for reproduction believed critical for the security and thermal protection of their young. Extirpated by the early 1900s from much of the continental United States due to trapping and poisoning, the species has recolonized many of its original northern habitats. With still very low numbers, fragmented populations and their habitat, particularly denning habitat, critically and directly threatened by climate change the wolverine was recently proposed for listing as threatened under the Endangered Species Act (http://www.fws.gov/mountain-prairie/species/mammals/wolverine/). A summary of information including past or on-going wolverine research can be found at www.wolverinefoundation.org.
Round River co-leads research with the USFS Rocky Mountain Research Station to answer critical questions about the potential effects of human disturbance on wolverines during winter and denning seasons. Even though anecdotal input and limited research have provided conflicting information regarding the sensitivity of wolverines to disturbance, there is increasing concern regarding the possible negative effects of winter recreation in areas used by reproducing female wolverine. The growing popularity of winter backcountry recreation combined with increasingly powerful snowmobiles is resulting in expanding winter human use in previously undisturbed public forest lands. The effects of this recreation on wolverine reproduction, behavior, habitat use and ultimately, on populations, is presently unknown and a growing concern given their uncertain status.
Round River, with a number of agency and stakeholder organizations, is implementing an intensive research effort to provide science-based information for land management decisions that may affect wolverines and winter backcountry enthusiasts. A powerful and unique aspect of this work is the diversity of partners it boasts, including state and federal agencies as well as backcountry snowmobile and ski organizations – we are all committed to ensuring that our actions do not negatively affect this unique species while ensuring winter recreation is sustained and sustainable.
- Goal 1 - To increase the science-based understanding of the effects of winter recreation on wolverine populations through examining wolverine behaviors, habitat use and reproductive efforts within landscapes supporting a diversity of winter recreation activities.
- Goal 2 - To provide science-based information to guide public land management for the sustainability of both winter recreation and wolverine.
Project Approach: Data are collected on wolverines by live-trapping and fitting Global Positioning System (GPS) collars on animals. Simultaneously, winter recreationists are asked to carry small GPS units that provide the path they have taken. The participation of winter recreationists is voluntary and anonymous, and the overwhelming majority of recreationists approached have participated.
Project Progress: Developing a sound, empirical understanding of the relationship between the wolverine and winter recreation requires considerable effort. The project has completed its 4th winter field season in 2013, and we are beginning to acquire valuable results. Still, the low number of wolverines found in any one area challenges the project, forcing a study design that requires either multiple study areas run simultaneously or moving to new study areas every few years to meet sample size requirements. To date, we have completed 2-3 years of work in 3 different study areas across the Boise, Payette and Sawtooth National Forests in central Idaho, and have instrumented 18 different individual wolverines over the 4 years. We are exploring options for additional work in these areas as well as establishing new study areas in Idaho and possibly Montana.
Please download the reports and progress updates for additional information on the project.
Project Partnerships: The project is a partnership with the National Forests, Idaho Fish and Game, the Idaho Snowmobile Association and a number of additional partners including ski resort and heliskiing interests. The project is led by the Forest Service’s Rocky Mountain Research Station (Dr. John Squires) and Round River Conservation Studies (Dr. Kimberly Heinemeyer), with critical funding support from agencies and non-government organizations including the Liz Claiborne Art Ortenberg Foundation and The Wolverine Foundation. The project uses the resources of all partners to combine an objective, science-based investigation with extensive community involvement and an information and education campaign.