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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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Monday, August 12, 2013

Connectivity is a challenge for Grizzly Bears moving back and forth between the Northern Continental Divide Sysyem and the Cabinet/Yaak System...........Biologists estimate that there are 15 to 25 Grizzlies in the Cabinet-Yaak and that if 11 Bruins had not been translocated to this "near island" closed-off system since 2005, a blinking out of the population might have already occurred............Female Griz do not reproduce until age 5 or 6 so when you have such a sliver of a population, "disappearance" can come rapidly.....................Nature Writer Rick Bass, the YELLOWSTONE TO YUKON advocacy Group and scores of like-minded land trusts and conservation Groups are fighting hard to create the type of protected large and connective corridors that would allow the Yaak Grizzlies to come, go and multiply to the point of sustainability

Grizzly bears on the move

Male moved to Cabinet Mountains
Another young male grizzly bear has been moved to the Cabinet Mountains from the Whitefish Range, and a female bear that was relocated two years ago has developed some remarkable traveling habits. The 3-year-old male was released west of Spar Lake July 31 after he was captured about 25 miles north of Columbia Falls. He is the latest in an ongoing grizzly bear population augmentation project for the Cabinet-Yaak recovery area.

The female was 2 years old when she was moved to the Cabinet Mountains in 2011. Just weeks later, she moved north into the Yaak and then east across Lake Koocanusa, eventually denning in Glacier National Park. After emerging from her den, she went to Waterton Lakes National Park in Canada and then trekked back to the West Cabinets, following the same path. She denned in the Cabinets at the end of 2012 and emerged this year to travel back to Waterton.
She now appears to be heading back to the Cabinets, most recently being located on the west side of Lake Koocanusa."She covers some ground," said Wayne Kasworm, grizzly bear biologist with the U.S. Fish and Wildlife Service in Libby. "It certainly is unusual in the natural scheme of things. Typically a young female that becomes independent of her mother is going to set up a home range adjacent to her mother's or use part of her mother's home range."

But this isn't the natural scheme of things, and Kasworm cautions against making the assumption that there is much connectivity between grizzly bears in the Cabinets and bears in the Northern Continental Divide Ecosystem. "I would be careful with that. This bear got over here in the back of a pickup truck," Kasworm said. "Before people make the assumption that there's connectivity here, you have to remember that."
Kasworm said he is unaware of any bears that reached the Cabinets from the east without the help of a pickup truck. He is aware of two males that moved west from the Cabinet-Yaak, one making it across Lake Koocanusa and the other making it to the Whitefish area. Both are now dead.
Since 1990, 14 bears have been added to the Cabinet-Yaak population, 11 of them since 2005, including seven females and four males. Captures, known mortalities and genetic analysis of collected hair samples have identified 37 individual grizzly bears that have occupied the Cabinets from 1997 through 2012.According to Kasworm, that information indicates the population may have been fewer than 15 bears prior to 1990. "The information also indicates that the Cabinet Mountains grizzly population would probably have disappeared without augmentation," Kasworm states in a recent report.
A female that was moved to the Cabinets in 1993 is known to have produced at least nine first-generation offspring, and those nine produced at least eight second-generation offspring. Kasworm said it is still unknown if any of the females moved since 2005 have reproduced, but he said it is possible. Because the bears are moved when they are 2 or 3 years old, it is difficult to keep track of them by the time they reach the reproductive age of 5 or 6 years old. "A lot of these bears that we're putting collars on are young bears, and by the time they reach reproductive age they've lost their collars," Kasworm said.
He added that an ongoing genetic population study led by U.S. Geological Survey researcher Kate Kendall in the Cabinet-Yaak region could yield evidence that transplanted female grizzly bears have reproduced.
Kasworm said there are plans to capture and relocate another female to the region this year if one can be found that meets certain criteria, most notably a lack of conflicts with humans.

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