The Wildlife Management Institute facilitated a recent workshop to finalize the protocol for the first ever range wide survey designed to estimate occupancy of wolverines in the Lower 48 states. Participants in the meeting included wildlife agency staff from Colorado, Idaho, Montana, Washington and Wyoming along with the USDA Forest Service Rocky Mountain Research Center and the National Forest system, the U.S. Fish and Wildlife Service (FWS), Confederated Salish and Kootenai Tribe (CSKT), Wolverine Foundation, Round River Conservation Studies, University of Montana, Colorado State University and the Woodland Park Zoo. Results of the survey discussed at the meeting will be used to prioritize efforts to maintain connectivity between occupied areas, to inform decisions about ways to restock suitable but currently unoccupied habitat in these and other western states, and as a statistically robust baseline to compare with future survey efforts.

Wolverines were largely extirpated from the Lower 48 states by the early to mid-1900s. Although the species has begun recolonizing some of its historic range in Washington, Idaho, Montana and Wyoming, estimating the actual size and distribution of the wolverine population is difficult and expensive due to the low densities, vast home range sizes and rugged nature of the habitat used by this species. Concerns about the status of wolverines led to a petition for listing under the Endangered Species Act, but the FWS ruled in 2014 that listing this species was not warranted. The four states are taking the initiative to advance wolverine conservation in order to preclude the need for listing.

Recent advances in non-invasive sampling using camera traps and hair snares that has been applied to numerous species have made it possible for the states to plan a range wide assessment of wolverine distribution over the next two winters. Working collaboratively with federal agencies, tribes, universities and NGOs, the states will use camera traps and hair snares located in a sample of 15 by 15 km grid cells spread across the landscape from the Cascades in Washington to the Bighorn Mountains in Wyoming. The goal of the study is to determine how much of the wolverine habitat identified by the two most commonly used models is actually occupied by the rare carnivore. The sample design was informed by a pilot project completed in Wyoming last winter as well as similar efforts in British Columbia and Alberta. Those projects demonstrated a high probability of detecting wolverines when they are present. Unique coloration and DNA from the hair snares allows researchers to identify many of the individuals detected by the surveys, which allows an even more in-depth understanding of the population.

Sampling of at least 100 of the 663 grid cells across the species' range in the four states will begin in Wyoming this winter. Bob Lanka, with the Wyoming Game and Fish Department, is eager to get the project started. "Wyoming is on the southern edge of current known wolverine distribution," said Lanka. "Two different models predict there is quite a bit of habitat in the state, but we don't know how much of that habitat is occupied. This survey will tell us where wolverines are and where they probably are not. With that information we can make more informed plans about ways to promote wolverine conservation." Sampling of cells in the other three states will occur in the winter of 2016-17.

Results of the survey may be used to prioritize areas between occupied patches of habitat to maintain connectivity. Wolverines' ability to move across large expanses to find mates and suitable habitat is important to the species' long-range survival. That's why the Great Northern Landscape Conservation Cooperative identified wolverines as one of their priority species. Information on the current distribution of wolverines can be used by agencies and land trusts to focus their efforts to maintain connectivity. Results may also be used to identify areas where translocation of wolverines could either fill in gaps in the current range or accelerate recolonization of areas in the southern Rockies or mountain ranges in Oregon and California where the species once roamed. Expanding the distribution of the species is seen as a potential hedge against the effects of climate change over the coming decades.

Any effort of this magnitude is expensive. Justin Gude, with the Montana Department of Fish, Wildlife and Parks explained that currently available funding is being provided through a $200,000 competitive multi-state wildlife grant, matched almost dollar-for-dollar with state money. "The Great Northern Landscape Conservation Cooperative is providing $75,000 for the first year's work and agreed to consider additional funding in 2016," said Gude. Scott Jackson, National Carnivore Coordinator for the Forest Service, offered to help fund the genetic analysis of wolverine hair samples and Stacy Courville, biologist for the CSKT, said the tribe would contribute by conducting the sampling of cells on their lands. The states also plan to apply for a grant from the National Fish and Wildlife Foundation that would allow them to increase the sampling effort as well as conduct more complete analysis of population genetics and connectivity. (cs)