Grazing, Ungulate, and Disturbance Ecology

Science Center Objects

We work with a diverse collection of other researchers and resource managers, at local to national and international levels, to address ways in which herbivory and grazing systems interact with the broader ecosystems in which they occur.  We investigate whether long-term weather patterns may interact synergistically to affect how soils, vegetation, and other animals respond to grazing or browsing by large mammals.  Our research typically takes a holistic view of grazing ecology, drawing in numerous pathways and components to not only understand how these arid and semiarid systems function, but to quantitatively assess the benefits and challenges of alternative grazing systems.  Over the past two decades, we have researched free-roaming horses, free-roaming burros, domestic sheep, and domestic cattle.  We blend rigorous research design with a solutions-oriented approach to provide empirical assessment of how this pervasive land use fits in to the bigger ecological and economic pictures.

Mt. Jefferson high plains.

Synecology of different herbivores and herbivore regimes in the High Plains

Location(s): northern Great Plains, to southern Canada (Montana, Wyoming, North Dakota, South Dakota)

Objectives: Answer the following questions:

  • Will the responses of soils, vegetation, and animals to grazing be altered by the interactive effects of long-term weather patterns and variability?
  • If so, which ecosystem components and portions of the landscape will be most vulnerable to declines?
  • Will patterns in occupancy of grassland-nesting birds act as ‘surrogate’ indicators of the patterns of occupancy and abundance of plants or other animals, or of ecosystem functions?
  • Is there an optimal frequency or duration of grazing, or length of rest from grazing that most consistently promotes conservation of birds, other species, and ecological functions such as preventing topsoil erosion?
  • How does remote sensing of vegetation relate to on-the-ground measurements, and what are the implications of different remotely-sensed classifications of pixels for management actions? What is the best scale for mapping land cover in support of management decisions?
  • What factors most strongly determine ecosystem responses to grazing in the Northern Great Plains region?

Funding: Past: Montana Institute on Ecosystems (EPSCoR), U.S. Geological Survey, University of Nevada-Reno

Collaborators: U.S. Fish & Wildlife Service, U.S. National Park Service, Bureau of Land Management, U.S.D.A. Agricultural Research Service, University of Montana, Montana State University, The Nature Conservancy, World Wildlife Fund, Montana Outdoor Science School, and the Montana Natural Heritage Program.

“Free-ranging horses and their management in semiarid ecosystems of western North America". American Society of Mammalogists conference; June, 2014.

“Landscape-scale approaches to investigate faunal response to ecological disturbances.” College of William and Mary; April, 2014.

“Mechanisms underpinning species and climate relationships.” Multi-agency meeting on Greater Sage-Grouse, climate, and land use; December, 2012.

“Using research on synecology of free-roaming horses in sagebrush communities of the Great Basin to address possible interactions of horses and Greater Sage-grouse.” Society for Range Management Annual Meeting; January, 2012.

“Within landscape-scale conservation and management paradigms, how does one detect disturbance "treatment" effects?” Pacific Island Ecosystems Research Center and partners; November, 2011.

“Long-term ecosystem responses to livestock removal in the Mojave Desert.” Ecological Society of America; August, 2011. [given by senior author, K. Veblen]