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SEVERAL DAYS ago, I related “A Coyote Tale” (www.wp.me/p2ETap-1B6), based on an article in Science magazine, published by the American Association for the Advancement of Science.
The AAAS article, “Predators in the ’Hood,” by Virginia Morell, also contained interesting accounts of other predators expanding their ranges. Bears and cougars (also known as mountain lions) are finding ways to coexist with humans.
David Mattson, a wildlife biologist with the U.S. Geological Survey, sees coexistence in a positive light: “Most of them try to avoid us.”
It isn’t that we don’t see them, though. Heather Johnson, a researcher with Colorado Parks and Wildlife, took an informal survey of school kids in Durango, Colorado: “If you ask them if they’ve seen a bear in the wild, one or two will raise their hands. But if you ask, ‘Have you seen a bear in your backyard?’ every hand goes up.”
TV news reports entertain with videos of bears doing one thing or another in town. My favorite (http://goo.gl/aCoMzS) is the one carefully selecting his favorite trash bin for a snack.
However, what’s to be done when this interaction is a threat to humans? Killing the animal is a quick answer, but cougars provide a compelling counterexample of the efficacy of this approach.
Deer, elk and bighorn sheep are the primary prey of the cougar, Puma concolor. However cougars have also been known to attack cattle, other livestock—and humans. The state of Washington responded by extending its hunting season, increasing the number of animals a hunter could take, and dropping the price of a hunting tag. (More than 66,000 tags were sold in 2007, though the state’s cougar population was estimated at fewer than 4000).
Cougar deaths skyrocketed. But so did livestock predation.
Researchers figured out why: This wildlife management model was patterned after the wrong animal, the white-tail deer. (“If there are too many deer, allow hunters to cull the herd.”)
With predators, though, the culling should be highly selective. Robert Wielgus, a wildlife ecologist at Washington State University at Pullman, is quoted in the Science article, “A stable cougar society has senior, adult males” who patrol large territories and protect the kittens of several females. If this male is eliminated, younger males become more aggressive, fighting for the territory and even killing kittens to promote their own genetic strain. What’s more, these inexperienced males are less likely to avoid human interaction.
In Washington now, cougars are no longer treated as a single population. Instead, the state recommends annual elimination of no more than 14 percent of males in any one of 49 “management units.”
California is a telling case in this regard. It has one of the west’s larger cougar populations, about 4000. Yet sport hunting of the animal is banned. California also has the west’s lowest rate of livestock depredation. ds
© Dennis Simanaitis, SimanaitisSays.com, 2013