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Grizzly bears, black bears, wolves, coyotes, cougars/ mountain lions,bobcats, wolverines, lynx, foxes, fishers and martens are the suite of carnivores that originally inhabited North America after the Pleistocene extinctions. This site invites research, commentary, point/counterpoint on that suite of native animals (predator and prey) that inhabited The Americas circa 1500-at the initial point of European exploration and subsequent colonization. Landscape ecology, journal accounts of explorers and frontiersmen, genetic evaluations of museum animals, peer reviewed 20th and 21st century research on various aspects of our "Wild America" as well as subjective commentary from expert and layman alike. All of the above being revealed and discussed with the underlying goal of one day seeing our Continent rewilded.....Where big enough swaths of open space exist with connective corridors to other large forest, meadow, mountain, valley, prairie, desert and chaparral wildlands.....Thereby enabling all of our historic fauna, including man, to live in a sustainable and healthy environment. - Blogger Rick

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Wednesday, July 25, 2012

The Inter-Agency Grizzly Bear Study Team that was formed in 1973 to monitor the status of the Grizzly population in the Yellowstone ecosystem is reporting that season to date this year 10 of the 16 Grizzly deaths have been determined to be of natural causes........Normally, this % of mortality is tied to human causes............Old age setting in on the population or is it a declining Whitebark Pine food source contributing to the death spiral?

National reports:

A spike in the mortality rate for grizzly bears has been reported in the Greater Yellowstone Ecosystem earlier in the season than is typical according to my colleague Frank van Manen. Dr. van Manen is the Team Leader of the Interagency Grizzly Bear Study Team and President of the International Association for Bear Research & Management.

Formed in 1973, to address specific concerns over the management of grizzly bears in the Greater Yellowstone Ecosystem (GYE), the Interagency Grizzly Bear Study Team monitors the status and population trends of grizzly bears in the region.

Essentially, the Team conducts research that will determine whether GYE grizzlies will retain “threatened” status under the Endangered Species Act.

Substantial changes in demographic and population trends in the GYE grizzly bears could influence policy and ultimately conservation status, which makes this report more of a significant finding.

Under the auspices of the Department of Interior, the Team is comprised of scientists representing the U.S. Geological Survey, National Park Service, U.S. Fish and Wildlife Service, U.S. Forest Service, the Eastern Shoshone and Northern Arapaho Tribal Fish and Game Department, and the States of Idaho, Montana, and Wyoming.

Although most deaths in the region at this time of season are usually human-caused, 10 of 16 grizzly bears monitored by the Team died of natural causes already this year. Although the data may warrant attention, biologists refrain from jumping to conclusions and caution others to do the same. “We should be careful not to make too much of this,” said Frank van Manen. “We’re seeing the typical range of conditions that we’d see with grizzly mortality.

“The fact that there were two females with cubs that were killed inflates the numbers a little bit,” van Manen said. ”We’re seeing an aging of the population as well. It wouldn’t surprise me if we start to see more of these bears dying from old age.” Concern over the declining population of whitebark pine stands due to mountain pine beetle infestations has been speculated as potential factor in the deaths of the bears. Whitebark pine tree seeds are an important pre-hibernation food source for grizzlies in the region.

But they are a critical late-season food source for grizzlies, not an earlier-season resource. So according to van Manen it is “probably too early to say” if the conifer plays a role in the mortality rate recorded thus far this season. In fact, seed production seemed “pretty reasonable” compared to productivity in the past few years, according to the bear biologist.

It remains to be seen what impact this mortality rate will have on the population of bears in the GYE, which numbers around 600 animals.

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