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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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Tuesday, January 13, 2015

A solid 6 year(2008-13) peer reviewed study of how human hunting impacts the recruitment of Wolves was just published in the publication, ANIMAL CONSERVATION.........This Northern Rocky Mountain research dovetails with findings in eastern Canada by Linda Rutledge et al. and Montana studies by Scott Creel and Jay Rotella that show how human hunting adversely impacts wolf recruitment.................All three studies reveal that it is not just the killing of the wolves but in fact the subsequent disruption of the social mores of the remaining pack animals that most often leads to pack abandonment and reduced populations................Thank you Ecologist, hunter and naturalist George Wuerthner for bringing this important new study to our collective attention


From: George Wuerthner []
Sent: Tuesday, January 13, 2015 9:45 AM
To: rick meril;
Subject: recruitment in social carnivore

Recruitment in a social carnivore before and after harvest


Knowledge about recruitment in a population can be critical when making conservation decisions, particularly for harvested species. Harvest can affect population demography in complex ways and this may be particularly true for cooperatively breeding species whose successful reproduction is often linked with complex social dynamics.

 We currently have a poor understanding of how harvest affects recruitment in cooperatively breeding species. We used non-invasive genetic sampling and a natural experiment to estimate recruitment in a population of gray wolves Canis lupus before and after harvest in the northern Rocky Mountains, US (2008–2013).

 We hypothesized that recruitment would decline after hunting and trapping began and that the decline in recruitment would be attributable to the harvest of pups and not to the subtler mechanisms associated with group dynamics and reduced reproductive success.

 We collected fecal samples from wolves in 10 packs for 6 consecutive years, extracted DNA and genotyped 154 individual pups across 18 microsatellite loci. Population harvest rates averaged 23.8% (sd=9.2). Our hypothesis that recruitment would decline was supported; survival from 3 to 15 months of age decreased from 0.60 [95% confidence interval (CI): 0.48–0.72] without harvest to 0.38 (95% CI: 0.28–0.48) with harvest and recruitment declined from 3.2 (95% CI: 2.1–4.3) to 1.6 (95% CI: 1.1–2.1) pups per pack after harvest was initiated.

 We cannot unequivocally dismiss other factors that could have reduced recruitment, however, an increase in recruitment when harvest temporarily ceased lends support to our conclusion that harvest reduced recruitment. We attributed just 18–38% of pup mortality directly to harvest and suggest that there are indirect effects of harvest on recruitment that may be associated with changes in group size and structure. Models that do not include both direct and indirect effects of harvest on recruitment may underestimate the potential impact of harvest on population growth in social species.


Effects of hunting on wolf populations(click on this link for article)

The recent debate concerning wolf management in the Northern Rocky Mountains (NRM) has focused in part on what type of long-term management approach is appropriate for recovered wolf populations. Often the normative or ethical debate over wolf hunting is difficult to separate from ecological questions such as what level of human-associated mortality (hunting, lethal control) can be sustained by wolf populations. Two new studies provide new insights on the latter question.

A new meta-analysis by Scott Creel and Jay Rotella in the journal PLoS One compares levels of human-associated mortality with mortality and population growth rates for wolf populations in both the NRM and elsewhere in North America.
(full article)

The authors found that human killing of wolves is generally not compensatory (an increase in human-caused mortality is not offset by a decline in natural mortality). Instead, human-associated mortality may be ‘super-additive’, in that, by e.g., disrupting pack structure, it leads to additional mortality among surviving wolves.

The study’s results imply that even initial wolf hunt quotas established by Montana and Idaho during the 2009 season are unsustainable, and that subsequent state proposals to increase these quotas further are likely to reduce wolf population size by a greater amount than estimated in state management proposals.

Related findings are presented in a recent study Linda Rutledge and colleagues in the journal Biological Conservation. The authors studied a wolf population in and around Algonquin Park, Canada, before and after implementation of a wolf hunting ban in surrounding townships.
(full article)

The authors found that in this population, a decline in human-associated mortality was compensated for by an increase in natural mortality, such that wolf density remained constant. However, pack structure changed with the decline in human-associated mortality, with the number of wolf packs with unrelated adopted animals decreasing from 80% to 6%. 

The effect of hunting on the social dynamics of wolf populations may be as important as the numerical effect. Even in a relatively large protected area, hunting of wolves outside park boundaries can affect wolf social patterns within protected areas. This has implications for NRM wolf management, for example in the area surrounding Yellowstone National Park, where the 2009 hunt removed a pack that primarily resided within the park.

Although NRM wolf populations are currently back under the protection of the federal ESA, the two studies’ findings have implications for the eventual transition to state management. Both of these studies imply that conservation of  populations of large carnivores will be complex and require approaches that are different than those applied to the game species that currently receive the most ocus from state wildlife management agencies



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