NRDC: The Bear Minimum
Based in Livingston, Montana, Louisa Willcox is NRDC's senior wildlife advocate and resident grizzly bear expert. OnEarth asked her about the threats facing American grizzlies.
Rick Bass reports that only about 25 brown bears remain in the Pyrenees. How does that compare to the situation of grizzly bears in this country?
Grizzlies in the Selkirks and Cabinet-Yaak ecosystems in Idaho and Montana are in a predicament that is quite similar to the bears Rick Bass sought in the Pyrenees. Each group has about 20 to 40 bears, and each is teetering on the edge of extinction. The reasons are similar, too: habitat loss and excessive human-caused mortality. The Selkirks and Cabinet-Yaak grizzlies are among the last five populations in the lower 48 states, which amount to just one percent of the number in the West 200 years ago. Exacerbating this problem of small numbers is the isolation of these groups from one another, which threatens their genetic health.
What are the main threats right now to the grizzlies in the Northern Rockies?
Bears are threatened by habitat loss and excessive human-caused mortality. Of particular concern are rural sprawl, energy development and associated transmission lines, as well as two new mine proposals. With the lowest reproductive rate of any mammal in North American, the grizzly bear is especially vulnerable to humans. Human-caused mortality rates are unsustainably high in all of the Northern Rockies populations.
NRDC is heavily involved in the loss of whitebark pine forests. Why is the tree so important to the Yellowstone grizzly, and what is happening to it?
Although grizzlies eat a variety of foods, from grass to buffalo, whitebark pine seeds are the engine that drives the health of the Yellowstone grizzly bear population. Whitebark pine forests are collapsing throughout the region, as a result of a non-native pathogen, white pine blister rust, as well as an unprecedented outbreak of mountain pine beetles, which are able to flourish in these high-elevation forests as a result of warming temperatures. NRDC is collaborating with the U.S. Forest Service and others on the first-ever comprehensive aerial assessment of whitebark pine health in the Greater Yellowstone Ecosystem: the picture is grim, and whitebark pine is functionally gone in much of the Greater Yellowstone.
Why do bears matter?
Because of their sensitivity to development and huge home ranges (200-400 square miles), grizzly bears serve as the barometer of the health of the ecosystems where they live. When grizzly bear populations are healthy, so are other wildlife species, from big game to birds.
What is the status of grizzly bears in the lower 48 states?
Only five grizzly bear populations remain in the lower 48 states, which is just one percent of the number that were here just 200 years ago. The five populations are in the Yellowstone, Glacier, Cabinet-Yaak, Selkirks, and North Cascades ecosystems. With the exception of the Yellowstone population, grizzlies in the lower 48 states are protected under the Endangered Species Act (ESA). Experts maintain that the grizzly bear would have disappeared in the lower 48 states but for the protections of the ESA. Yellowstone's bears were removed from the endangered species list in 2007, and NRDC is challenging thar decision in court.