Grizzly Bear Monitoring in the North Cascades

At one time grizzly bears (Ursus arctos) roamed throughout the wild areas of Washington. Since their near extirpation from the lower 48 states in the 1800’s, grizzly bears were listed as endangered under the Endangered Species Act in 1975. In 1997 the North Cascades, along with five other recovery zones, was identified as a key area for recovery of the endangered bear species. Despite anecdotal reports of grizzlies in the North Cascades, no population or individuals has been confirmed in the area. Based on expert opinion and a database of sightings, the U.S. Fish and Wildlife Service believe there are fewer than 20 grizzly bears remaining in Washington’s North Cascades ecosystem. The British Columbia Ministry of Environment estimates there are six grizzly bears in the Canadian North Cascades.

In 2010, with oversight from the North Cascades Interagency Grizzly Bear Subcommittee, the Cascade Carnivore Connectivity Project (CCCP) and other project partners began an extensive survey to detect grizzlies potentially occupying Washington’s North Cascades Ecosystem (NCE). CWMP’s effort to detect grizzly bears in the NCE is designed to complement the work already carried out by the CCCP. Locations for surveying are selected based on the sampling model created by CCCP and the sampling method they employed based on the “hair corral” described by Kendall and McKelvey (2008). CWMP’s field methods are adapted from these methods to focus on simple detection using remote camera data rather than DNA analysis based on genetic sample (hair) collection. CCCP’s primary research objectives where to collect information on the genetic structure of carnivore populations in the NCE and secondarily to detect grizzly bears and other rare carnivores. CWMP’s primary research goal is detection of grizzly bears.