University of Idaho’s iconic research study reveals significant outcomes

University of Idaho (U of I) concluded a 10-year research study on Greater sage grouse and cows coexisting on the same land without declines in sage grouse nest success or insect abundance. In fact, the research study revealed there are positive outcomes when sage grouse and cattle live side by side.

The decade-long research project was prompted by opposition to spring cattle grazing on federal lands in the early 2000s, and the lack of scientific data on the subject spurred the project, which wrapped up data collection in August 2023.

Sage grouse in the West

Sage grouse are known for their elaborate mating display and live in sagebrush habitat across nine Western states.

However, populations have declined in recent years due to increased damage to sagebrush habitat, and federal officials have debated whether to list the bird under the Endangered Species Act (ESA).

Listing sage grouse on the ESA would impact energy and agriculture development in these regions, as grazing is one of the most extensive uses of rangeland throughout the West.

But, U of I Professor Courtney Conway led a recent research study, stating there wasn’t enough science documented to illustrate how cattle grazing affects sage grouse nesting areas to inform decision makers.

U of I captured and studied dozens of sage grouse hens, while sampling vegetation and invertebrates at multiple plots across Idaho to determine how cattle grazing affected sage grouse predation, nesting and population health.

Moderate cattle grazing doesn’t hurt sage grouse nesting success

According to a U of I news article published on Oct. 24, Conway states, “Nesting success doesn’t seem to be affected by low to moderate levels of cattle grazing, and insect biomass increases with grazing.”

The university adds, “Conway joined forces with U of I Professor of Rangeland Ecology Karen Launchbaugh, biologists in the Bureau of Land Management – the agency which oversees much of sage grouse habitat in Southern Idaho – Idaho Fish and Game, several ranchers who have grazing permits within sage grouse habitat and other partners in Idaho to bring scientific data to the debate.”

Conway’s group of researchers annually collected and analyzed data from five research sites in Idaho and worked closely with local ranchers who agreed to participate in the long-term project.

“I think this is a significant outcome for the ranching community, which has wondered all along what they would do if scientists learned their spring grazing was bad for grouse,” notes Launchbaugh, co-lead investigator. 

“Had we found spring grazing had a negative effect on grouse populations, it could have resulted in the loss of grazing allotments on federal land, something cattle ranchers – especially smaller operations – need for their businesses to survive,” she continues.

The research study identified several benefits to cattle living next to the birds. Cattle can often attract insects to an area, and bugs serve as excellent nutrition for sage grouse chicks.

Melissa Anderson is the editor of the Wyoming Livestock Roundup. Send comments on this article to roundup@wylr.net.