New study presents good news for Yellowstone grizzly bears
A new study offers another indicator that Yellowstone region grizzly bears are thriving — and they have the potential to thrive a while longer.
The study, published in Molecular Ecology, looked at 729 bears and found that the effective population — the number of bears passing genes to the next generation — in Yellowstone has quadrupled since the 1980s, growing from 100 to about 450. Researchers also found that genetic diversity in the population was stable.
That means gene variations that can help grizzlies evolve and adapt have a better chance of being passed on to new generations of Yellowstone bears. That’s important for their continued survival, especially in the age of climate change.
Pauline Kamath, a geneticist and one of the study’s authors, said the results are good for the grizzlies and highlight their restoration as a “conservation success.”
This study comes as the U.S. Fish and Wildlife Service is said to be mulling a delisting rule for the threatened species. The bear was first listed as threatened under the Endangered Species Act in 1975, and has been hailed as one of the law’s biggest successes. The most recent U.S. Geological Survey estimated the total Yellowstone grizzly population at 757 bears, though some guess it’s even higher.
Kamath said the growth in effective population coincided with the growth in overall population, which could be one of the reasons the results came out the way they did.
She also said the stability in genetic diversity is some of the most significant good news in the study.
“As you lose genetic diversity you lose specific gene variants that will allow populations to adapt,” she said. “The less diversity you have, the less you have to work with basically.”
Grizzly bears only live in a few places around the Northwest, and the Yellowstone population isn’t connected to any of them. Because of that, there’s no way for fresh genes to be injected into the population, meaning genetic diversity will always be decreasing.
“It’s inevitable that an isolated population will lose diversity over time,” Kamath said.
But, Kamath and the other researchers found, because of the large effective population, the decline in genetic diversity has been gradual.
“There’s a very slow decrease,” she said.”But it’s not significant
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PURPOSE OF AND NEED FOR ACTION
REINTRODUCING GRIZZLIES INTO THE BITTEROOTS
President Bush(the younger) blocked this action when he became President
A BIG ERROR AND BAD DECISION BY HIM
PURPOSE OF THE ACTION
Grizzly bears (Ursus arctos horribilis) are a part of America's rich wildlife heritage and once ranged throughout most of the western United States. However, distribution and population levels of this species have been diminished by excessive human-caused mortality and loss of habitat. Today, only 800 to 1000 grizzly bears remain in a few populations in Montana (Northern Continental Divide, Yellowstone, and Cabinet-Yaak Ecosystems), Idaho (Yellowstone, Cabinet-Yaak, and Selkirk Ecosystems), Wyoming (Yellowstone Ecosystem), and Washington (Selkirk and North Cascades Ecosystems). Wildlife species, like grizzly bear, are most vulnerable when confined to small portions of their historical range and limited to a few, small populations. Expansion of the range of the species will increase the number of bears within the lower 48 states and increase habitat size and extent, and further conservation of the species.
The Grizzly Bear Recovery Plan (USFWS 1982) called for evaluation of the Bitterroot Ecosystem (BE) as a potential recovery area. The best scientific evidence available indicates there are no grizzly bears in the BE at this time (USFWS 1996). Based on the results of a 5-year study (Davis and Butterfield 1991) of the BE, bear scientists estimate that the area could eventually support more than 200 grizzly bears (Servheen et al. 1991). The Interagency Grizzly Bear Committee (IGBC) endorses the BE as a grizzly bear recovery area. The IGBC is a group of high-level administrators that represent the federal and state agencies involved in grizzly bear recovery, and coordinate agency efforts in implementing the Grizzly Bear Recovery Plan.
The USFWS, with support of the IGBC, proposes to recover the grizzly bear and restore this component of the BE by reestablishing the species within this portion of its historical range. The recovery of grizzly bears in the BE will allow the return of this prominent native omnivore now missing from this large block of Rocky Mountain wilderness habitat. The USFWS has determined that there are no grizzly bears in the BE at this time, that recovery of grizzly bears in the BE would facilitate conservation and recovery of the species in the lower 48 States, and that recovery of grizzly bears in the BE would require reintroduction of bears from other areas (USFWS 1993, 1996). The action proposed in this DEIS is to reintroduce a minimum of 25 grizzly bears over a 5-year period from which a population could grow over time.
A public survey conducted in 1995 (Duda and Young 1995) indicated that 64% of local, 74% of regional, and 77% of national respondents were supportive of reintroducing grizzly bears into the BE. The two most popular reasons given by respondents for supporting reintroduction were the desire to save the grizzly bear from extinction, and to return this species as a missing component of the ecosystem.
The BE is one of the largest contiguous blocks of federal land remaining in the lower 48 United States. The core of the ecosystem contains the Selway-Bitterroot and Frank Church-River of No Return Wilderness Areas. Together these two wilderness areas make up the largest block of wilderness habitat in the Rocky Mountains south of Canada. Of all remaining unoccupied grizzly bear habitat in the lower 48 States, this area in the Bitterroot Mountains has the best potential for grizzly bear recovery, primarily due to the large wilderness area. As such, the BE offers excellent potential to recover a healthy population of grizzly bears and to boost long-term survival and recovery prospects for this species in the contiguous U. S. The potential for grizzly bear recovery will be enhanced in the lower 48 States by inclusion of the BE because habitat will be increased by almost 10,000 square miles or almost 25% (including the wilderness area and outside buffer zones). In addition, any new or additional populations of grizzly bears will add to the known populations and therefore provide for a higher recovery potential for the species as a whole, decreasing the amount of time the species is on the Endangered Species List and the regulatory burden placed on the public. Other outcomes of reintroduction of the grizzly bear to the BE include its potential delisting and eventual return to state management where human uses could include hunting. The recovery of the grizzly bear in the BE would also aid in restoration of Nez Perce Tribe cultural and spiritual values
related to the grizzly.
NEED FOR THE ACTION
Biological. A metapopulation can be defined as a set of spatially disjunct populations, among which there is some potential immigration (Wells and Richmond 1995). Given understanding of population biology and metapopulation dynamics, the chances of survival of grizzly bears south of Canada increase as more populations are added to a grizzly bear metapopulation. Each additional population decreases the overall total number of grizzly bears that are necessary for long-term survival of the metapopulation. Also, each additional population reduces the number of bears that are necessary in each individual population within the metapopulation. This suggests that for grizzly bears to survive in the lower 48 States, each additional population with potential linkage to other populations increases the probability of survival. Therefore, one way to achieve recovery of grizzly bears in the lower 48 States and assure survival is to establish several smaller populations of grizzly bears. The ability of the Yellowstone population to contribute to a metapopulation has been questioned because of geographic distance to other populations and habitat fragmentation, although evaluation of this possibility is continuing (USFWS 1993). The addition of the BE to the grizzly bear recovery effort will increase long-term survival probabilities and conservation of grizzly bears within the lower 48 States.
BACKGROUND
For thousands of years, grizzly bears lived in a variety of habitats throughout most of western North America. An estimated 50,000 grizzly bears roamed the American West prior to European settlement (USFWS 1993). Due to loss of habitat and excessive and intentional killing by people, grizzly bears have been eliminated from all but approximately 2 percent of their historic range in the lower 48 States (USFWS 1993).
Historically, the grizzly bear was a widespread inhabitant of the Bitterroot Mountains in central Idaho and western Montana. When Lewis and Clark traveled through the Bitterroot country in 1806, grizzly bears were abundant. They killed at least 7 grizzly bears including 1 female and 2 cubs while camped near present-day Kamiah, Idaho (Thwaites 1959). Grizzly bears were common in central Idaho until the early 1900's (Wright 1909, Merriam 1922, Burroughs 1961). Wright (1909) wrote of killing dozens of grizzly bears over several years in the Bitterroot Mountains. A major influx of hunters, trappers, and settlers at the turn of the century, and later sheepherders were responsible for direct mortality and elimination of grizzly bears from the BE. Conservative estimates indicate trappers and hunters killed 25 to 40 grizzly bears annually in the Bitterroot Mountains during the early 1900's (Moore 1984, 1996). The last verified death of a grizzly bear in the BE occurred in 1932 and the last tracks were observed in 1946 (Moore 1984, 1996). Although occasional unverified reports of grizzly sightings persist in the BE (Melquist 1985), no verified tracks or sightings have been documented in more than 50 years.
the Bitterroot Grizzly Bear Primary Analysis Area (PAA) and includes USDA Forest Service lands potentially affected by grizzly bear recovery in the BE of Idaho and Montana (Figure 1-1). The heart of the PAA is centered around Wilderness Areas of central Idaho, while a small portion extends over the crest of the Bitterroot Mountains into western Montana.
The PAA includes about 16,686,596 acres (26,073 square miles) of contiguous national forest lands in central Idaho and western Montana (see Figure 3-2 in Chapter 3). These include all or parts of the Bitterroot, Boise, Challis, Clearwater, Nez Perce, Payette, Sawtooth, Salmon, and Panhandle National Forests in Idaho, and the Bitterroot and Lolo National Forests in western Montana.
scattered parcels of
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