Friday, August 1, 2014

Ms. Cristina Eisenberg graces our Blog for a 2nd consecutive day as the lead author(with colleagues Bill Ripple, D.E. Hibbs and H. Salwasser) focusing on THE LANDSCAPE OF FEAR paradigm and how it played out in both Glacier National Park in Montana and Wateron Lakes National Park in Alberta, Canada........What is so continually interesting about the study of Wildlife(and the human animal) is that continued observation and evaluation seems to lead to "exceptions to existing rules and theories,,,,," and sometimes, even readjustment or abandonment of rules..............Cristina and crew discovered that not all Elk herds react the same to landscapes containing moderate and dense populations of Wolves.............Taking into account "landscape impediments" to escaping from Wolves such as distance to forest edge, group size, distance to roads and social class, Cristina and team did not record consistent levels of behaviour in the Elk herds they monitored...............More study is needed but Ms. Eisenberg concludes by saying that "Where a high wolf population existed, elk did not exhibit uniform or expected response to predation risk factors"............. "High wolf presence may necessitate adaptive elk behaviour that differs from response to moderate wolf presence"



From: Eisenberg, Cristina ;Cristina.Eisenberg@oregonstate.edu
Date: Friday, August 1, 2014
 To: Rick Meril ;rick.meril@gmail.com
Subject: Eisenberg et al predation risk paper!

Dear Rick,

I have attached our most recent scientific journal article, which is about predation risk.

Please share with your readers!

 Cristina

 p.s.There is no link to the full article, as that is not available without a subscription, this is not an open-access journal. The link below (the only one I have that is accessible freely) provides access to the abstract and citations:http://www.nrcresearchpress.com/doi/abs/10.1139/cjz-2014-0049#.U9vfELHcOt9

Context Dependence of Elk Vigilance and Wolf Predation Risk

Eisenberg, C., D. E. Hibbs, W. J. Ripple, and H. Salwasser.
Can. J. Zool. 92: 727–736 (2014) dx.doi.org/10.1139/cjz-2014-0049

Abstract
To assess the relationship between predation risk perceived by elk, Cervus elaphus (L., 1758), as evidenced by vigilance, we conducted focal animal observations in elk winter range.

We stratified our observations in Glacier National Park, Montana and Waterton Lakes National Park, Alberta, in valleys with three wolf, Canis lupus, (L., 1758), population levels (Saint Mary Valley: no wolf; Waterton Valley: moderate wolf; and North Fork Valley: high wolf).



While the lowest elk vigilance occurred in Saint Mary and the highest in the North Fork, our analysis revealed a complex picture. Our model included distance to forest edge, group size, distance to road, social class, and impediments to detecting and escaping wolves.

In Saint Mary, none of the variables were significant. In Waterton, vigilance decreased as elk group size increased (p<0.00001) and increased as impediments increased (p=0.0005). In the North Fork, vigilance increased as group size increased (p=0.03), bulls were more vigilant (p=0.02), and the interaction between group size and impediments was significant (p=0.03).

Where a high wolf population existed, elk did not exhibit uniform or expected response to predation risk factors. High wolf presence may necessitate adaptive elk behaviour that differs from response to moderate wolf presence.

Keywords: elk (Cervus elaphus), focal sampling, pr




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