Project Supervisor
Dr. Craig Paukert

Funding
Kansas Cooperative Fish and Wildlife Research Unit

Cooperators
U.S. Bureau of Land Management, Gunnison, Colorado

Objectives
Determine the impacts of elk browsing on vegetation.

Determine how drought impacts grazing of elk on vegetation.

Location
Gunnison, CO

Expected Completion
December 2009
 

Progress and Results
High populations of wintering game can have detrimental impacts on the growth and survival of browsed shrubs.  Severely browsed shrubs can have stunted growth, smaller crowns, and this can lead to increased death.  Even species such as bitterbrush, which has growth that is stimulated by browse, will reduce the number of buds produced under heavy browsing.  Mountain mahogany shows good tolerance to winter browsing but may have reduced growth and be unproductive by repeated browsing.  Serviceberry can withstand moderate to strong levels of browsing and defoliation.  However, continued browsing will increase twig production and keep the shrubs from growing out of reach of big game.  Under herbivory, shrubs will expend the most energy into increased leader growth, although this energy is lost if the new leaders are repeatedly browsed.  The objectives of this study are to determine if elk browsing effects shrubland growth and if drought can also play a part on reduced shrubland vegetation.  A total of 37 permanent transects were established in key browse areas.  During April/May of 2001 and 2006, the extensive browse method was conducted on the transects.  This study focuses on age class, form class, and size on three key browse species; Utah serviceberry, mountain mahogany, and antelope bitterbrush.  Results indicate that browsing did differ among species but not necessarily between years, suggesting responses to elk browsing do differ by shrubland species.

Products
A manuscript is in preparation for the Journal of Range Management.