Home Archived April 13, 2016

Cabinet-Yaak Grizzly Bear Project 2011-2013


Principal Investigator

Katherine C. Kendall, USGS Glacier Field Station, Glacier National Park, West Glacier, MT 59936-0128 kkendall@usgs.gov


  • Estimate of Population Size: Use sign surveys and systematic hair snag stations to obtain an estimate of the number of grizzly bears in the Cabinet-Yaak Ecosystem (CYE) in northwest Montana and northeast Idaho.
  • Genetic Library: Develop a genetic database for grizzly bears in the CYE to assess genetic diversity and degree of relatedness of the CYE grizzly bear population.


North American range map for grizzly bears (Ursus arctos)Grizzly bears (Ursus arctos horribilis) once roamed most of the North American continent. Habitat destruction and direct conflicts with humans have reduced their range by 99% in the lower 48 states (right, click on map for larger version). In 1975 grizzly bears were listed as threatened under the Endangered Species Act. The Cabinet-Yaak Ecosystem (CYE) in northwest Montana and northeast Idaho is one of six recovery zones defined in the Grizzly Bear Recovery Plan (U.S. Fish and Wildlife Service 1993). The CYE is the fourth largest in area and contiguous to a small Canadian population. Estimates place the total number of grizzlies that remain south of the Canadian border at fewer than 1100. It is thought there are between 30-40 animals within the 2,600 square-mile Cabinet-Yaak recovery zone. For more information about grizzly bear recovery, visit the U.S. F&WS Grizzly Bear Recovery Office webpage.

Study Area

The study area includes 9,850 km2 (2,433,988 acres) of grizzly bear-occupied area and encompasses the 6,765 km2 Cabinet-Yaak Recovery Zone plus 3,110 km2 of occupied range that fall outside it (Fig. 1). The eastern bounds of the study area, in northwest Montana, extend from the Canadian border south along the western shore of Lake Koocanusa to include the Purcell Range surrounding the Yaak River drainage, trend west to Libby at the confluence of Barron Creek, then southeast following the Cabinet Range's eastern valley shoulder to the study area's southern bound 15 km west of Plains. The western boundary then extends northwest, following the Lower Clark Fork River to the town of Trout Creek , trends west into Idaho to include the northeast side of the Bitterroot Range, then follows a northerly direction along the western valley shoulder of the Coeur d'Alene, Cabinet and Purcell Ranges to the study area's northern bound at the Canadian border in northeast Idaho.
The study area contains parts of three national forests (Kootenai, Idaho Panhandle, and Lolo) that include one wilderness area, Cabinet Mountains (382 km2), and one proposed wilderness area, Scotchman Peaks (356 km2). There are 2,175 km of maintained trail, 6,530 km of open roads, and 8,330 km of gated, bermed, closed, and private roads in the CYE study area. The study area is a region of diverse land use with rugged mountains in the wilderness areas surrounded by multiple-use forest lands. National forest and corporate timber lands have active timber harvest and forest management programs. The study area also includes an active silver and copper mine, two proposed silver and copper mines, and a closed vermiculite mine area (14.5 km2) that is not available for sampling due to asbestos contamination. The major valley bottoms are primarily private lands with a mix of forested and open parcels and variable density of towns, rural residences, small farms and ranches.

Field Methods

Update will occur soon

Genetic Methods


Genetic analysis can determine the species, gender, and unique identity of a bear using the DNA contained within their hair. Prior to DNA extraction, each hair sample is examined to identify and isolate intact follicles. Acceptable DNA extraction rates are achieved with hair samples with at least two follicles and are the standard for this project. The hair follicles (2-10) are inserted into a solution that breaks down the membrane that surrounds the DNA in the follicle. The samples are then repeatedly "washed" chemically to remove any cellular debris and then stored in a refrigerator until DNA analysis is conducted.


Specific regions (called microsatellites) in the nuclear DNA (n DNA) are amplified (copied) using an optimized polymerase chain reaction (PCR). Electrophoresis is used to separate the DNA segments alongside a standard set of DNA (DNA segments of known length). The length of the amplified DNA segments yields species, unique identity, and gender information.

Data Analysis Methods

Update will occur soon


Field Results: No results at this time. Fieldwork begins May 2011

Genetic Analysis: No results at this time.

Data/Statistical Analysis: No results at this time.

Related Publications


Related Materials

Related Projects

  • Northern Divide Bear Project (2003-2008): project website
  • Greater Glacier Bear DNA Project (1997-2002): project website
  • Use of Remote Camera Systems: Remote video and still cameras were used to: investigate how grizzly bears, black bears, and other wildlife species respond to baited, barbed wire hair traps; bear use of naturally-occurring bear rubs, bear marking behavior, and effects of putting barbed wire on bear rubs to facilitate hair collection; how hair traps may be modified to improve detection probabilities. Use of remote camera systems to investigate efficiency of DNA-based sampling methods


grizzly bear, black bear, DNA finger printing, mark-recapture, wildlife, population, landscape scale, non-invasive sampling, conservation genetics, hair, microsatellites, polymerase chain reaction, Ursus arctos, Ursus americanus, hair snag, sign survey, genetics, Kootenai National Forest, Cabinet-Yaak Ecosystem, Montana, Idaho

Geographic Distribution

Cabinet-Yaak Ecosystem, Northwest Montana