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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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Sunday, April 10, 2016

Sympatric species like Gray Wolves and Western Coyotes, Eastern Coyotes and Red and Gray Foxes find a way to co-exist in the same system via the less dominant creature seeking a niche that the dominant creature need not pursue for optimum survival.............Same is true for where Black Bears and Grizzly Bears occupy habitat.............The less dominant Black Bears will avoid the key sections of the forest(and be more active during the day whereas dominant male Grizzlies are more active at night) where Grizzlies make their stand...........A recently studied "sympatric avoidance" paradigm reinforces this phenomena in southwestern Alberta, Canada, where an increasing grizzly bear presence has Black Bears not showing their face as they once did........... Dominance hierarchy and predation avoidance hypotheses suggest that grizzly bears alter the feeding behaviour, activity patterns, and home range sizes of black bears.

Black bears avoid grizzlies

Black bears avoid grizzlies

What do bears do in the woods? They rub on trees, for one thing.
That particular habit allowed University of Alberta researcher Andrea Morehouse to collect hair left on particularly attractive scratching sites.
She used the hair from grizzly bears to test their DNA and get a more accurate count on their numbers in southwestern Alberta.
Grizzly Bear

However, black bears like to rub, too, and now their hair is being tested by Annie Loosen, a U of A masters student and researcher.
Loosen used hair collected in 2013 and 2014 to identify 347 black bears in Alberta’s bear management area six, which is south of Highway 3. Trail cameras show that not all bears stop to rub, said Loosen. They may sense a more dominant black bear has already rubbed or they may be intimidated by evidence of a grizzly bear.
That means collected hair samples can’t be relied on to tell the population story. However, Loosen said there hasn’t been an update on Alberta black bear populations for 20 to 30 years. There is a hunting season for black bears and they are generally considered to be more plentiful than grizzlies.
Morehouse’s research has found that at least 213 grizzly bears live or pass through the study area, and black bears tend to avoid grizzlies.
“Landowners, fish and wildlife officers, provincial biologists have noticed that black bears aren’t in places that they’ve usually been,” said Loosen.
 Black bear

“There’s some suggestion that black bears are altering movements or range in response to a growing grizzly bear population.”
For more information, visit

Journal of Wildlife Management

Published by: The Wildlife Society

Journal of Wildlife Management 74(8):1628-1638. 2010
Contrasting Activity Patterns of 
Sympatric and Allopatric Black
 and Grizzly Bears

Grizzly Bear

Black Bear

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