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Yellowstone wolf restoration

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By Northern Prairie Wildlife Research Center June 26, 2018

The National Park Service and U.S. Fish and Wildlife Service reintroduced wolves into Yellowstone National Park in 1995 and 1996. This study helps assess that population’s recovery and determine factors that affect the population, including diseases, intraspecific strife, and interactions with prey. The restoration has been very successful, and the population has persisted for more than 20 years despite it being affected by canine distemper, mange, and other diseases.  The Yellowstone wolves’ primary prey has always been elk, and we and other researchers have learned much about the interactions between the two species. One of the remaining questions was what factors affect the rate at which wolves encounter elk, a key factor in determining wolf hunting success rate.  Based on 46 wolf pack study periods from 2004 to 2012, only elk density influenced wolf encounter rate of elk, despite tests of season, snow depth, elk-group density, mean-elk group size, wolf-pack size and territory size.

Below are publications associated with this project.

Can we save large carnivores without losing large carnivore science?

Large carnivores are depicted to shape entire ecosystems through top-down processes. Studies describing these processes are often used to support interventionist wildlife management practices, including carnivore reintroduction or lethal control programs. Unfortunately, there is an increasing tendency to ignore, disregard or devalue fundamental principles of the scientific method when communicatin
Authors
Benjamin L. Allen, Lee R. Allen, Henrik Andrén, Guy Ballard, Luigi Boitani, Richard M. Engeman, Peter J.S. Fleming, Peter M. Haswell, Adam T. Ford, Rafał Kowalczyk, John D.C. Linnell, L. David Mech, Daniel M. Parker
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center

Large carnivore science: non-experimental studies are useful, but experiments are better

We recently described the following six interrelated issues that justify questioning some of the discourse about the reliability of the literature on the ecological roles of large carnivores (Allen et al. In press): 1. The overall paucity of available data, 2. The reliability of carnivore population sampling techniques, 3. The general disregard for alternative hypotheses to top-down forcing, 4. Th
Authors
Benjamin L. Allen, Lee R. Allen, Henrik Andrén, Guy Ballard, Luigi Boitani, Richard M. Engeman, Peter J. S. Fleming, Adam T. Ford, Peter M. Haswell, Rafał Kowalczyk, John D. C. Linnell, L. David Mech, Daniel M. Parker
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center

Sexually dimorphic aggression indicates male gray wolves specialize in pack defense against conspecific groups

Aggression directed at conspecific groups is common among gregarious, territorial species, and for some species such as gray wolves (Canis lupus) intraspecific strife is the leading cause of natural mortality. Each individual in a group likely has different measures of the costs and benefits associated with a group task, such as an aggressive attack on another group, which can alter motivation and
Authors
Kira A. Cassidy, L. David Mech, Daniel R. MacNulty, Daniel R. Stahler, Douglas W. Smith
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center

Territoriality and inter-pack aggression in gray wolves: shaping a social carnivore's life history

When Rudyard Kipling wrote The Jungle Book in 1894 and included the famous line "For the strength of the Wolf is the Pack, and the strength of the Pack is the Wolf," he would have had no idea that over a century later, scientific research would back up his poetic phrase. Recent studies in Yellowstone have found that both the individual wolf and the collective pack rely on each other and play impor
Authors
Kira A. Cassidy, Douglas W. Smith, L. David Mech, Daniel R. MacNulty, Daniel R. Stahler, Matthew C. Metz
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center

The National Park Service and U.S. Fish and Wildlife Service reintroduced wolves into Yellowstone National Park in 1995 and 1996. This study helps assess that population’s recovery and determine factors that affect the population, including diseases, intraspecific strife, and interactions with prey. The restoration has been very successful, and the population has persisted for more than 20 years despite it being affected by canine distemper, mange, and other diseases.  The Yellowstone wolves’ primary prey has always been elk, and we and other researchers have learned much about the interactions between the two species. One of the remaining questions was what factors affect the rate at which wolves encounter elk, a key factor in determining wolf hunting success rate.  Based on 46 wolf pack study periods from 2004 to 2012, only elk density influenced wolf encounter rate of elk, despite tests of season, snow depth, elk-group density, mean-elk group size, wolf-pack size and territory size.

Below are publications associated with this project.

Can we save large carnivores without losing large carnivore science?

Large carnivores are depicted to shape entire ecosystems through top-down processes. Studies describing these processes are often used to support interventionist wildlife management practices, including carnivore reintroduction or lethal control programs. Unfortunately, there is an increasing tendency to ignore, disregard or devalue fundamental principles of the scientific method when communicatin
Authors
Benjamin L. Allen, Lee R. Allen, Henrik Andrén, Guy Ballard, Luigi Boitani, Richard M. Engeman, Peter J.S. Fleming, Peter M. Haswell, Adam T. Ford, Rafał Kowalczyk, John D.C. Linnell, L. David Mech, Daniel M. Parker
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center

Large carnivore science: non-experimental studies are useful, but experiments are better

We recently described the following six interrelated issues that justify questioning some of the discourse about the reliability of the literature on the ecological roles of large carnivores (Allen et al. In press): 1. The overall paucity of available data, 2. The reliability of carnivore population sampling techniques, 3. The general disregard for alternative hypotheses to top-down forcing, 4. Th
Authors
Benjamin L. Allen, Lee R. Allen, Henrik Andrén, Guy Ballard, Luigi Boitani, Richard M. Engeman, Peter J. S. Fleming, Adam T. Ford, Peter M. Haswell, Rafał Kowalczyk, John D. C. Linnell, L. David Mech, Daniel M. Parker
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center

Sexually dimorphic aggression indicates male gray wolves specialize in pack defense against conspecific groups

Aggression directed at conspecific groups is common among gregarious, territorial species, and for some species such as gray wolves (Canis lupus) intraspecific strife is the leading cause of natural mortality. Each individual in a group likely has different measures of the costs and benefits associated with a group task, such as an aggressive attack on another group, which can alter motivation and
Authors
Kira A. Cassidy, L. David Mech, Daniel R. MacNulty, Daniel R. Stahler, Douglas W. Smith
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center

Territoriality and inter-pack aggression in gray wolves: shaping a social carnivore's life history

When Rudyard Kipling wrote The Jungle Book in 1894 and included the famous line "For the strength of the Wolf is the Pack, and the strength of the Pack is the Wolf," he would have had no idea that over a century later, scientific research would back up his poetic phrase. Recent studies in Yellowstone have found that both the individual wolf and the collective pack rely on each other and play impor
Authors
Kira A. Cassidy, Douglas W. Smith, L. David Mech, Daniel R. MacNulty, Daniel R. Stahler, Matthew C. Metz
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center
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