Northern Continental Divide Ecosystem
The grizzly bear (Ursus arctos horribilis) occupies over 6 million wilderness and non-wilderness acres in the Northern Continental Divide Ecosystem (NCDE) of western Montana. Notable regions within this ecosystem include Glacier National Park and the Bob Marshall wilderness complex. Grizzlies were listed as Threatened under the Endangered Species Act in 1975 for lack of biological information on its population status and habitat requirements. The NCDE is believed to have the largest population in the lower 48 states. It is estimated from a 2004 DNA study that there are over 700 bears in the ecosystem.
Information on both population size and trend are needed. Having estimates of size and trend will greatly improve our collective knowledge of grizzly bear ecology, and provide more measurable and precise information to judge the status of the grizzly population in the NCDE. Therefore, Montana Fish, Wildlife and Parks, in cooperation with other state and federal agencies, initiated a program in 2004 to monitor the population trend of grizzly bears in NCDE. The purpose of this long-term program is to monitor the vital population parameters of grizzly bears by assessing the survival and reproductive rates, and trend. This will be accomplished by radio-monitoring female grizzly bears.