The importance of browse communities for mule deer and implications of fire and invasive annual grasses: Bitterbrush and Kochia case studies

Authors: Clements, Darin - Charlie; JEFFRESS, MATT - Nevada Department Of Wildlife; MCADOO, CALEB - Nevada Department Of Wildlife

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/21/2023
Publication Date: 8/18/2023
Citation: Clements, D.D., Jeffress, M., Mcadoo, C. 2023. The importance of browse communities for mule deer and implications of fire and invasive annual grasses: Bitterbrush and Kochia case studies. Meeting Abstract. 1:8.

Interpretive Summary:

Technical Abstract: In big sagebrush communities, wildfires are the primary stand renewal process. Excessive grazing reduced grasses and brought about the reduction in fine fuels to carry wildfires. The shrubs then became larger, more vigorous, and established in higher densities. This vegetation change was beneficial to mule deer herds throughout the West. In more than a century, big sagebrush plant communities in the Great Basin have gone through periods of; 1) pristine wildfire frequency with aboriginal burning, 2) promiscuous burning, 3) attempted complete suppression of wildfires, and 4) attempts at prescribed burning and let-burn policies for wildfires. Historically, wildfires in the northern Great Basin experienced wildfire intervals of every 60-110 years and mostly occurred in the late summer after the perennial grasses had flowered and dried out. The accidental introduction of cheatgrass and its’ subsequent invasion onto millions of acres of Great Basin rangelands has increased this wildfire interval to a reported 5-10 years. The accidental introduction and subsequent invasion of cheatgrass significantly contributed to the transformation of millions of acres of wildlife habitats throughout the West, especially browsers such as mule deer. With each passing wildfire season more and more critical shrub communities are burned and converted to cheatgrass dominance. Restoration of critical browse species, such as antelope bitterbrush, as well as using range improvement practices, which include aggressive weed control programs and seeding of introduced grasses and shrubs to rehabilitate degraded mule deer habitats will play an important role in reversing the current downward trend in mule deer populations. Utilizing nutritional introduced shrub species such as 'Immigrant' and 'Snowstorm' forage kochia will provide nutritional forage on mule deer transitional and winter ranges. The management of mule deer and their habitat is complex as numerous factors play a role in the health, or lack of mule deer herds throughout the Great Basin. Understanding that many factors are associated with the health of mule deer herds should be understood and addressed. Improving habitat conditions of summer, transitional and winter ranges can increase fawn production, decrease breeding female mortality, decrease winter mortality, decrease predation, and increase carrying capacity. The efforts put forth today are critical if our future mule deer herds are to have suitable habitat that will be in demand in the near future as well as decades down the road.