Monitoring Bear Populations with Non-Invasive Sampling 2008-2014

Principal Investigator

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

Project Description

The goal of this research project is to evaluate the effectiveness of noninvasive sampling to monitor trends in the threatened grizzly bear population in the Northern Continental Divide Ecosystem (NCDE) of northwestern Montana. This work uses hair collection methods similar to those used in the 2004 to estimate population abundance in the NCDE as part of the Northern Divide Grizzly Bear Project. However, instead of generating a snapshot of population size, this new work will collect bear hair over multiple years to determine how the population changes over time. We will use detections of individual bears at un-baited, naturally-occurring bear rubs (trees, posts, and poles that bears rub on) to examine population trends, including changes in abundance, survival rate, regional density, and genetic structure. Hair collected from bear rubs can detect a large portion of the population. For example, over half of all male grizzlies and a quarter of all females in the population were detected on bear rubs in 2004. By sampling rubs throughout the NCDE and sampling in late summer and fall, we expect to detect even more of the population each year. Collecting hair from bear rubs promises to be a safe, reliable, and cost-effective way to sample bear populations and monitor their status over time.

For more information click here: Project Objectives

Related Materials

Related Projects

  • Use of Remote Camera Systems (2004-present): We use remote video and still cameras were used to investigate 1) how grizzly bears, black bears, and other wildlife species respond to baited, barbed wire hair traps; 2) bear use of naturally-occurring bear rubs, including bear marking behavior, and the effects of putting barbed wire on bear rubs to facilitate hair collection; 3) how hair traps may be modified to improve detection probabilities. Use of remote camera systems to investigate efficiency of DNA-based sampling methods
  • Northern Divide Bear Project (2003-2008): project website
  • Greater Glacier Bear DNA Project (1997-2002): project website


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, Glacier National Park, Blackfoot Nation, Flathead National Forest, Helena National Forest, Kootenai National Forest, Lewis and Clark National Forest, Lolo National Forest, Bob Marshall Wilderness, Mission Mountains, Great Bear Wilderness, Scapegoat Wilderness, Northern Continental Divide Ecosystem

Geographic Distribution

Northern Continental Divide Ecosystem, Northwest Montana