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Large Predators and Wildlife Restoration

On May 1, eleven conservation groups filed suit in Arizona federal court asking the U.S. Fish and Wildlife Service (FWS) to reclaim leadership for the Mexican wolf reintroduction effort rather than shifting the management to an oversight committee. With only fifty-two Mexican gray wolves remaining in the wild, far below FWS’s goal of one hundred by 2006, the organizations argue that wolf conservation should be a priority. On the same day, David Perlman’s front-page article in the San Francisco Chronicle reported on a new study that offers evidence for the importance of wolves—and other large predators—in the landscape. Oregon State University researchers William Ripple and Robert Beschta examined what happened in Yosemite National Park as populations of mountain lions declined. They found that as cougars disappeared, the numbers of mule deer increased, which in turn meant more browsing of black oak seedlings. Eventually, as black oaks were replaced by pines and firs, the entire ecology of the area changed. Scientists call this ecosystem-wide chain reaction to the loss of a large predator a trophic cascade. The theory is controversial and still being fleshed out with research around the world, but I find it fascinating: tangible evidence of the intricate complexity and interdependence of wild nature. Still, I’ll confess that trophic cascades are not the first thing that pops into my mind when I think “mountain lion.” Instead, I envision the fluid grace, the long tail, the “charisma” of the big cat. Although I live in mountain lion territory, it was seventeen years before I first saw the local large predator in the flesh. When that finally happened—when a big cat loped casually behind my house on a Sunday morning in February—my slightly romantic mental image gave way to the real animal, whose breathtaking presence in my home landscape continues to evoke not only awe but also humility. If you would like to read an excerpt from Michael Morrison’s Wildlife Restoration: Techniques for Habitat Analysis and Animal Monitoring (as well as samples of fourteen other books in the SER series), click here for a free download of the SER Restoration Reader.