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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, May 3, 2015

We have discussed Trophic Cascades and how top of the food chain carnivores like Wolves work in concert with bottom up trophic factors(rain/soil and resulting herbivory) to keep our natural systems in a rough equilibrium, operating so that all species fulfill their ecological functions.............Today we report on a 2013 JOURNAL OF ECOLOGY peer reviewed article entitled: RECOLONIZING WOLVES TRIGGER A TROPHIC CASCADE IN WISCONSIN..........Researchers from New York, Wiconsin, Ohio and Georgia tested the hypothesis of whether Wolves are reducing the browsing pressure of white tail deer in Wisconsin............Read full article by clicking on link below to absorb fully how the "LANDSCAPE OF FEAR" paradigm put forth by researchers Bill Ripple and John Laundre do appear to be at work in the Wisconsin woods, the first evidence of Wolf triggered trophic cascade reducing the impact of deer on the herbivory...............In the authors own words-----"If the methods employed here were applied across other forest types, we could predict long-term, region-wide effects of reintroducing top predators to this and other terrestrial systems"........... "Our results indicate that wolf recovery in other regions of North America (such as the northeastern United States) could be vital to maintaining the ecological integrity of northern white cedar wetlands (and potentially other temperate and boreal forest systems as well)".............. "Whether efforts should be focused on reintroducing wolves or on increasing the connectivity between existing wolf populations and unoccupied wolf habitat should be carefully considered"..........................A special thank you to Rachel Tilseth of WOLVES OF DOUGLAS COUNTY(WISCONSIN) for sending me this article

Recolonizing wolves trigger a trophic cascade in Wisconsin (USA)

Ramana Callan1 *, Nathan P. Nibbelink2 , Thomas P. Rooney3 , Jane E. Wiedenhoeft4 and Adrian P. Wydeven4 1 State University of New York College of Environmental Science and Forestry, Box 37, Wanakena, NY 13695, USA; 2 Warnell School of Forestry and Natural Resources, The University of Georgia, 180 E. Green Street, Athens, GA 30602, USA; 3 Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Hwy, Dayton, OH 45435, USA; and 4 Wisconsin Department of Natural Resources, 875 S 4th Street, Park Falls, WI 54552, USA

Summary 1. We tested the hypothesis that wolves are reducing local browse intensity by white-tailed deer, thus indirectly mitigating the biotic impoverishment of understorey plant communities in northern Wisconsin.

 2. To assess the potential for such a top-down trophic cascade response, we developed a spatially and temporally explicit model of wolf territory occupancy based on three decades of wolf monitoring data. Using a nested multiscale vegetation survey protocol, we compared the understorey plant communities of northern white cedar wetlands found in high wolf areas with control sites found in low wolf areas.

3. We fit species–area curves for plant species grouped by vegetation growth form (based on their predicted response to release from herbivory, i.e. tree, seedling, shrub, forb, grass, sedge or fern) and duration of wolf territory occupancy.

 4. As predicted for a trophic cascade response, forb species richness at local scales (10 m2 ) was significantly higher in high wolf areas (high wolf areas: 10.7 0.9, N = 16, low wolf areas: 7.5 0.9, N = 16, P < 0.001), as was shrub species richness (high wolf areas: 4.4 0.4, N = 16, low wolf areas: 3.2 0.5, N = 16, P < 0.001). Also as predicted, percentage cover of ferns was lower in high wolf areas (high wolf areas: 6.2 2.1, N = 16, low wolf areas: 11.6 5.3, N = 16, P < 0.05).

5. Beta richness was similar between high and low wolf areas, supporting earlier assumptions that deer herbivory impacts plant species richness primarily at local scales. Sampling at multiple spatial scales revealed that changes in species richness were not consistent across scales nor among vegetation growth forms: forbs showed a stronger response at finer scales (1–100 m2 ), while shrubs showed a response across relatively broader scales (10–1000 m2 ).

 6. Synthesis. Our results are consistent with hypothesized trophic effects on understorey plant communities triggered by a keystone predator recovering from regional extinction. In addition, we identified the response variables and spatial scales appropriate for detecting such differences in plant species composition. This study represents the first published evidence of a trophic cascade triggered by wolf recovery in the Great Lakes region.

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