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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, September 2, 2012

"Wolf restoration has generated a fine assortment of interesting ecological studies and has generally improved our understanding of wolves and associated species and their interactions with each other and the environment"............. "However, we as scientists and conservationists who deal with such a controversial species as the wolf have a special obligation to qualify our conclusions and minimize our rhetoric, knowing full well that the popular media and the internet eagerly await a chance to hype our findings"........ "An inaccurate public image of the wolf will only do a disservice to the animal and to those charged with managing it"........"The wolf, while at the top of a food chain and a restored member of the world’s most famous National Park(Yellowstone) and a prominent member of others, remains as one more species in a vast complex of creatures interacting the way they always have"....... "It is neither saint nor sinner except to those who want to make it so"-----David Mech, quoted from his eye-opening peer reviewed article entitled: "IS SCIENCE IN DANGER OF SANCTIFYING THE WOLF?"..................One of our leading Wolf Biologists in all of the Americas, Mech warns that just as the ranchers, farmers and some hunters are quick to lay all of societies ills at the foot of the Wolf, so are some researchers and journalists too quick to bestow accolades on the Wolf for its role in the circle of life-------Many, many factors involved in how Wolves impact trophic cascades in an ecosytem just as there are many, many factors involved in prey reductions that occur in a wolf involved system................... Mech's full article(access below) and Dr. Jeremy Bruskotter's(Professor, Ohio State) take on the Mech article are must Labor Day reading for all of us-----Many thanks to both Ralph Maughan's THE WILDLIFE NEWS and George Wuerthner for providing access to these fine articles

Of Wolves and Trophic Cascades: On the Costs and Benefits of Wolves

The reintroduction of wolves to Yellowstone National Park turned the nation’s most prominent national park into a laboratory of sorts, whereby scientists could document and measure the effect of wolves on a variety of other species. Since their return, dozens of studies have been published purporting to show some effect of wolves on some other component of the Yellowstone ecosystem. These studies, and associated work in the popular news media, have credited wolves with a variety of effects, most prominently, the regeneration of willow and aspen (e.g., Ripple & Beschta 2006, 2007). In a recent (June, 2012) article published in the journal, Biological Conservation, Mech pointed out that most of the so-called “effects” of wolves reported in the popular media were based upon correlative evidence and, perhaps more importantly, the validity of many of these claims are being challenged by emerging science (Mech 2012). He went on to accuse scientists and the popular news media of “sanctifying the wolf” by disproportionately covering the positive impacts (or benefits) of wolves.

do wolf kills really benefit scavangers and mesocarnivores as much as previously thought?

On the “effects” of wolves
Mech provides several examples where recent evidence conflicts with initial studies that documented some effect of wolves. So, for example, Mech notes that a number of studies have found that wolves tend to reduce coyote populations (see Ballard et al. 2003); however, while just such an effect was initially documented in parts of Yellowstone, coyote populations have since rebounded, returning to pre-wolf levels. More prominently, Mech notes that despite the claims of some researchers that wolves have caused a “trophic cascade”–i.e., increasing willow and aspen by reducing the number of elk in the Northern Range herd and changing elk foraging behavior–there is still no consensus on the cause of elk decline in this area (Vucetich et al. 2005, for example, argued that hunter harvest was primarily responsible for the decline and elk) and new evidence suggests elk are not modifying the behavior in the presence of wolves (e.g., Kauffman et al. 2010).

willow and aspen release-the impact of wolves on elk or is there more to it?

Are scientists and the news media “sanctifying” the wolf?
Mech’s primary point is a good one. Specifically, people should not take as gospel the correlative studies that have thus far been published regarding wolves’ beneficial effects. What scientists don’t know about wolves’ effects on Yellowstone is still vast relative to what we think we have sorted out. And determining how they effect species in more heavily managed areas (e.g. national forests) will (no doubt) be even more challenging (Mech 2012). However, Mech loses loses me when he accuses scientists and the news media of “sanctifying the wolf”:

“But what explains the rash of recent research purporting to show beneficial effects of wolves beyond releasing vegetation? With wolf lay advocates it is just natural to want to promote their favorite animal and to try to counter the known negative effects of wolves and the claims fostered by people who vilify wolves, an increasing lot as wolves recover and proliferate. Thus wolf advocates eagerly seize on any study they consider favorable to wolves. The media become complicit by immediately publicizing such studies (Table 1) because of the controversial nature of the wolf. And all this publicity reverberates on the internet. Seldom, however, do studies contradicting the sensational early results receive similar publicity” (Mech 2012, p. 146).

After a Wolf kill, is enough "meat" leftover for Grizzlies, Coyotes, Foxes, Ravens, etc?

Certainly, there is little doubt that some advocates of wolves would “sanctify” the wolf by reporting only those effects deemed beneficial. Mech is on solid ground there. However, Mech’s fundamental claim is that the news media (and science) is biased in favor of the wolf. Mech contends, for example, that “few recent studies have been published and popularized about what the public might consider negative about wolves”. Here, the empirical evidence does not support Mech’s view. While Mech relies on 11 purposively selected news articles as evidence of bias, Houston et al. (2010) recently reviewed more than 6,000 articles–totaling almost 30,000 paragraphs of text. In contrast to Mech’s claims, they noted that more than 70% of the paragraphs coded over a ten-year time period portrayed wolves negatively. Moreover, they found that while 2.3% of the paragraphs they coded concerned wolves’ beneficial impacts on ecosystems, the exact same proportion (i.e. 2.3%) discussed their negative impacts on ecosystems. Finally, they found that 30.5% of the paragraphs discussed wolves’ negative impact on human activities, whereas only 2% claimed a positive impact on human activities. The evidence here is quite clear–there is no indication that the news media is biased in favor of wolves; indeed, the evidence points strongly in the other direction.

Mech’s primary point–that correlative evidence is insufficient for establishing causation–is important, and I hope it does not get lost here. Despite decades of research, we know very little about wolves and their effects on ecosystems. However, for every story that claims some benefit of wolves on ecosystems, there are an equal number that claim some negative impact–some cost. And what we know about the costs of wolves is just as uncertain as what we know about the benefits.

Literature Cited
Ballard, W.B., Carbyn, L.N., Smith, D.W., 2003. Wolf interactions with non-prey. In: Mech, L.D., Boitani, L. (Eds.), Wolves: Behavior, Ecology and Conservation. University of Chicago Press, pp. 259–271.
Houston, M., Bruskotter, J.T. & Fan, D., 2010. Attitudes Toward Wolves in the United States and Canada: A Content Analysis of the Print News Media, 1999–2008. Human Dimensions of Wildlife 15(5), 389-403.
Kauffman, M.J., Brodie, J.F., Jules, E.S., 2010. Are wolves saving Yellowstone’s aspen? A landscape-level test of a behaviorally mediated trophic cascade. Ecology 91, 2742–2755.
Mech, L.D., 2012. Is science in danger of sanctifying the wolf? Biol. Conserv. 150, 143-149.
Ripple, W.J., Beschta, R.L., 2006. Linking wolves to willow via risk-sensitive foraging by ungulates in the Northern Yellowstone ecosystem. Forest Ecol. Manage. 230, 96–106.
Ripple, W.J., Beschta, R.L., 2007. Restoring Yellowstone’s aspen with wolves. Biol. Conserv. 138, 514–519.
Vucetich, J.A., Smith, D.W., Stahler, D.R., 2005. Influence of harvest, climate, and wolf predation on Yellowstone elk, 1961–2004. Oikos 111, 259–270.
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About The Author

Jeremy Bruskotter

Dr. Jeremy Bruskotter is an assistant professor in the School of Environment and Natural Resources at the Ohio State University where his research interests are centered around the “human dimensions” of wildlife conservation and management. Jeremy is passionate about wildlife–at one time or another, he has called himself hunter, angler, and wildlife photographer. Most of all, Jeremy is concerned with bringing the tools and techniques of the social sciences to bear on pressing issues in wildlife management.

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