Researchers release a collared cow elk in the foothills of the Sierra Madre Mountains
in southern Wyoming. Elk in that region avoid areas of the forest where a bark beetle
epidemic has killed lodgepole pine trees, newly published research shows. Among those
involved in this release were: at left, Wyoming Game and Fish Department biologist
Tony Mong; second from left, Wyoming Cooperative Fish and Wildlife Research Unit Director
Matt Kauffman; third from left, UW graduate student Bryan Lamont; and far right, UW
Assistant Professor Kevin Monteith. (Wyoming Cooperative Fish and Wildlife Research
Unit Photo)
Loss of the heat-shielding forest canopy and the obstacle of fallen trees have caused
elk to avoid beetle-killed areas of the Medicine Bow-Routt National Forest, according
to new research by University of Wyoming scientists.
Those factors more than offset the gains in nutritious grasses and other vegetation
desired by elk that have resulted from the region’s bark beetle epidemic, says the
research led by recent UW master’s degree graduate Bryan Lamont and supervised by
UW Professors Kevin Monteith and Matt Kauffman of the Wyoming Cooperative Fish and
Wildlife Research Unit. As with many wildlife studies in Wyoming, this was a collaborative
effort between university researchers and biologists with the Wyoming Game and Fish
Department, who are charged with managing the elk herd amid the massive forest disturbance.
“Although it is common following forest disturbances for elk to seek out and capitalize
on the resulting increases in highly palatable and nutritious forage, during the summer
months, elk in our study area fairly consistently avoided beetle-kill,” Lamont says.
“This result is somewhat counter to how we typically think elk respond to forest disturbances.
It appears there are some subtle but real differences between disturbances such as
forest fires and the bark beetle epidemic.”
The research, published in the Journal of Wildlife Management, suggests that removal of standing dead trees and downed logs in the beetle-killed
forests of the Sierra Madre Mountains might benefit the area’s population of 6,500-8,500
elk. As it is, the bark beetle epidemic “has altered how elk use the landscape and
has resulted in a potential loss of forest habitat that elk use during the day,” the
scientists wrote.
Downed trees resulting from the bark beetle epidemic pose a significant obstacle for
elk in the Sierra Madre Range. (Wyoming Cooperative Fish and Wildlife Research Unit
Photo)
The research involved collaring and GPS tracking of 71 female elk between 2012-16
in the Sierra Madres, where thousands of acres of lodgepole pine trees have been killed
by bark beetles in the past two decades. The beetle epidemic there peaked around 2009,
so the study period took place when trees were just beginning to fall.
The researchers found that, while previous studies showed elk often move into areas
disturbed by fires or timber harvest to take advantage of new plant growth, that isn’t
happening in the Sierra Madres. In fact, the elk strongly avoid beetle-killed areas
in the summer. That’s likely because elk must expend significant amounts of energy
to walk over downed logs and cool themselves in the beetle-killed areas.
“Ultimately, this means that if elk are avoiding beetle-killed areas, this translates
to much less forest habitat that elk typically would utilize during the summer,” Lamont
says.
The findings provide valuable insights for wildlife and land managers across the West,
who face challenges from the bark beetle epidemic “that have not been encountered
in modern wildlife management,” the paper says.
“Treating beetle-killed areas with excessive standing dead and downed trees through
prescribed fire or other removal techniques may be effective at reducing the negative
costs to elk from beetle-killed forests; provide elk with the adequate mixture of
foraging areas and hiding and thermal cover; and potentially decrease conflicts caused
by redistribution,” the scientists concluded.
