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Executive Summary

There is still time to restore the threatened grizzly, but only by adopting a broader vision of bigger connected ecosystems, protecting ecosystems large enough to account for likely environmental changes, and learning from the past successes and failures in efforts to resolve human-bear conflicts. Recent research reveals that there is still room enough to reach a population of 3000 grizzlies (roughly twice current numbers), by reconnecting grizzlies in Yellowstone to Canadian source populations, and restoring grizzlies to the now-vacant Selway/Bitterroot ecosystem.

Over the last fifty years, we have learned much about the ecology and biology of the bear, and about how to anticipate and resolve bear conflicts caused by garbage, livestock and hunters. We have much to celebrate, because grizzly bears remain in the lower 48 states as a result of 29 years of protection under the Endangered Species Act (ESA).

But, the world in which we live is rapidly changing. Escalating human population growth, rural sprawl, energy development and off-road vehicle use will continue to degrade grizzly bear habitat and further isolate island populations. Global climate change will reduce key grizzly bear foods that contribute to reproductive success and lower levels of human-caused mortality. Introduced diseases will also likely reduce key bear foods such as whitebark pine seeds, forcing bears to expand their movements to procure the calories needed to survive winter sleep and to reproduce successfully.

If current trends continue, the Cabinet Yaak grizzly population will likely disappear, and a similar fate may await the Selkirk and North Cascades. Such events would make the Yellowstone and Glacier populations more isolated and vulnerable to extinction. Such facts as well as worldwide trends, elicited the following prognosis from author David Quammen for grizzlies and other large carnivores. In Monsters of God, he writes, "call me a pessimist, but when I look into the future, I don't see any lions, tigers or bears. . .my guess, a regretfully gloomy one, is that the last wild, viable, free ranging populations of big flesh eaters will disappear somewhere around the middle of the next century. I see the year 2150 as a probable end point to the special relationship between us and them. . .that's not far off -- less than eight human generations. It is just time enough to encompass a welter of uncertainties, along with one weighty inevitability: the continuing growth of human population and consumption."

But, we need not and should not accept such a fate for an animal that is a wild icon, lying at the heart of the western experience, and the meaning of national parks such as Yellowstone, Glacier/Waterton, and Banff. We should start by refining the current approaches and protections that are now working to increase bear numbers in Yellowstone. In addition, we need to do more to protect habitat and reduce human-bear conflicts and resulting mortalities. This plan is a step in that direction.

This plan is built on several assumptions. First, because grizzly habitat encompasses whole ecosystems (4 million acres or larger), its conservation means maintaining large landscapes and ecological processes, such as fire, that drive them. Second, the impact of people on bears must be incorporated, because bears tend to flourish where people are relatively few in number. Third, limiting rates of human-caused mortality is essential to maintaining an animal with such a low reproductive rate; a small change in the rate at which people kill bears quickly makes a big difference in the health of populations. Fourth, given major questions about the future, it is important to protect large enough areas, so that grizzlies can find alternative foods and secure habitat in a future environment that will continue to change -- perhaps very quickly. This means that bears will need to occupy habitat they do not presently live in, to make up for habitat quality that will likely decline in core areas such as Yellowstone Park. Fifth, we seek to ensure that populations are both demographically robust -- greater than 400 animals -- and if possible, evolutionarily robust -- over 2,000 animals (see maps below) -- so as to survive environmental changes in the short and long terms. Research has shown that for mammals, several thousand interacting individuals are required to maintain genetic diversity over thousands of years. Given the current configuration and numbers of remaining bears in the lower 48 states, evolutionarily robust levels can only be achieved though expanding the areas where bears can be, and through connecting grizzly ecosystems from Yellowstone to Canada to ensure exchange of individuals and genes.

This last assumption distinguishes this plan from the current approach taken by the U.S. Fish and Wildlife Service (FWS) in the 1992 grizzly bear recovery plan. The FWS plan looks forward only 100 years, and seeks to maintain minimum population levels, with numbers roughly the same as when the populations were listed. Further, FWS manages all remaining ecosystems as isolated populations. These are located in northern Idaho (Selkirks), Northern Continental Divide (NCDE) near Glacier Park, northwest Montana (Cabinet Yaak), northern Washington (North Cascades), northern Montana (Glacier/Waterton) and Greater Yellowstone (GYE). And together they number still only 1000-1500 -- roughly the same number as at the time of listing. In addition, FWS maintains that Yellowstone bears can be recovered and subsequently removed from ESA protections, or delisted, as an isolated population of 400-500 animals, even though the agency recognizes that bears will likely need to be imported every ten years or so to avoid genetic inbreeding.

The scientific underpinnings of this alternative path are based on a core/corridors approach described by Reed Noss and others. The model consists of large core areas connected by linkage areas aimed at providing safe passage for bears. The purpose is to allow interchange of individuals between two or more populations, increasing the likelihood of survival of all populations.

Linkage areas are identified by the location of core areas, proximity of core areas to each other and the quality in the habitat. In the context of connecting grizzly bear ecosystems, the term "corridor" is a bit of a misnomer, as what is actually required are large tracts of linked habitat.

Map of grizzly populations

Courtesy of Troy Merrill, LTB Institute of Landscape Ecology

This plan is based on three peer-reviewed cores/corridors habitat assessments, developed over the past six years by Paul Paquet, Reed Noss and Carlos Carroll; Lance Craighead; and Dave Mattson and Troy Merrill. Despite different methods, these studies show largely similar results in terms of suitable core habitat and linkage areas between grizzly ecosystems. Here, we attempt to apply this scientific information in a practical plan for action to ensure the health of grizzlies for the benefit of generations yet unborn.

Mid-term conservation of grizzly bears

Courtesy of Troy Merrill, LTB Institute of Landscape Ecology

Long-term conservation of grizzly bears

Courtesy of Troy Merrill, LTB Institute of Landscape Ecology

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