THE ROLE OF UNGULATE HERBIVORY AND MANAGEMENT ON ECOSYSTEM
PATTERNS AND PROCESSES: FUTURE DIRECTION FOR THE STARKEY PROJECT
Martin Vavra
Team Leader, USDA Forest Service, Pacific Northwest Research Station
1401 Gekeler Lane, La Grande OR, 97850 Phone (541-962-6561) Fax (541-962-6504),
email mvavra@fs.fed.us
Michael J. Wisdom
Research Wildlife Biologist, USDA Forest Service, Pacific Northwest Research Station
1401 Gekeler Lane, La Grande, OR 97850 Phone (541-962-6532) Fax (541-962-6504),
email mwisdom@fs.fed.us
John G. Kie
Research Wildlife Biologist, USDA Forest Service, Pacific Northwest Research Station
1401 Gekeler Lane, La Grande, OR 97850 Phone (541-962-6529) Fax (541-962-6504),
email jkie@fs.fed.us
John G. Cook
Project Leader, National Council for Air and Stream Improvement
1401 Gekeler Lane, La Grande, OR 97850 Phone (541-962-6536) Fax (541-962-6504),
email cookjg@eou.edu, and
Robert A. Riggs
Research Wildlife Biologist, Boise Building Solutions, La Grande, OR 97850
Phone (541-962-2046) Fax (541-962-2002),
email RobertRiggs@BoiseBuilding.com
In the western United States, the effects of herbivory by wild ungulates have not been recognized
as a force of important ecological relevance as evidenced by lack of its mention in management
plans. Historically, biologists have made a distinction between livestock and native herbivores:
whereas livestock have been clearly perceived as agents of ecosystem disturbance, native
herbivores such as deer and elk usually are perceived as benign constituents of the environment.
More recently, however, empirical evidence suggests that ungulate herbivory, wild or domestic
can have dramatic effects on ecosystem structure and function. Successional pathways cannot be
predicted without regard to the herbivory regimes that may be expected to occur, underscoring
the need to understand how interactions between herbivores and episodic disturbance function, in
the context of both wild and domestic herbivory. Forest conditions in the western United States
are such that major changes are likely in the coming decades. Dense forest understories,
resulting from fire suppression, tree mortality caused by insect and disease outbreaks, and
ungulate grazing, have contributed to the current situation. In the coming years, conflagrations
will continue on forests where excessive fuel build-up has occurred, and extensive fuels
reduction projects will be initiated to prevent them. In both cases secondary succession will be
initiated and herbivory will influence Successional pathways and outcomes. We completed a
summary of existing knowledge of the influence of ungulate herbivory on ecosystem patterns
and processes and applied this information to identify research needs. Future research will focus
on the improving our knowledge on herbivory effects and its relationship to disturbance, which
can then be utilized to build and validate multi-scale models as a fundamental paradigm for
research and main tool for management applications. It is expected that this ongoing research
will interface with and be an integral part of related ungulate research in the interior Pacific
Northwest.