Editor's Note: Sagebush is the dominant plant species in the Great Basin, especially in valley bottoms, plateaus and mountain foothills. Sagebrush provides habitat for a variety of animals in the region, most notably the sage grouse, which is declining as a species because of human activity like cattle grazing and gas drilling.
By George Wuerthner
Management with the Challis and Salmon Bureau of Land Management (BLM) districts in Central Idaho appear ready to destroy much of the sage grouse habitat in the nearby Lemhi, Pahsimeroi and Lost River valleys, ironically in the name of protecting sage grouse, in a destructive sagebrush "mowing" effort on 134,000 acres of public land in the Gem State.
As an ecologist, and someone who has studied both sagebrush and sage-grouse ecology, I find the proposal to crush over 130,000 acres of sagebrush in prime and associated sage grouse habitat almost criminal. I do not use that term lightly.
There is abundant scientific evidence that demonstrates sagebrush is critical to sage grouse survival. Currently, much of the area proposed for "treatment" doesn't even meet the BLM's minimum levels of sagebrush cover for sage grouse — thus destroying tens of thousands of acres of sagebrush can only lead to the continued decline of sage grouse in the area.
There is also abundant evidence that disturbance of sagebrush landscapes leads to an increase in cheatgrass. Cheatgrass is an invasive annual grass that is highly flammable. Since it can increase wildfire frequency in sagebrush landscapes, it is one of the significant threats to sagebrush ecosystems and sage grouse.
But cheatgrass does not suddenly appear from space or with aliens. Instead, the spread of cheatgrass is a direct consequence of disturbance that harms native grasses and landscapes. One recent study in Oregon that compared mowed and unmowed sagebrush sites concluded: "By the third year post-treatment annual forb and annual grass (cheatgrass) biomass production was more than nine and sevenfold higher in the mowed than reference treatment."
Another 2012 study found: "The preponderance of literature indicates that habitat management programs that emphasize treating (like mowing) Wyoming big sagebrush are not supported concerning positive responses by sage-grouse habitats or populations." The same study went on to conclude: "Most published information suggests that treatments to winter or breeding habitats of sage-grouse have a negative effect on the species."
And research published this year concludes that "grazing impacts resulted in reduced site resistance to B. tectorum, suggesting that grazing management that enhances plant and biocrust communities will also enhance site resistance" to cheatgrass. Translation: If you want healthy sagebrush ecosystems, remove the irritations like livestock grazing.
Beyond the fact that these treatments are likely to increase cheatgrass at the expense of sagebrush and sage grouse, the real threat to sage grouse in these valleys, and elsewhere across much of its range, is livestock production. Yet the BLM does not even consider the cumulative impacts of sagebrush destruction with the ongoing, adverse effects of domestic livestock production on these same lands.
If the BLM really wanted to improve things for sage grouse, it would be eliminating livestock grazing on OUR public lands.
For instance, much research has shown that the trampling of biological crusts enhances the spread of cheatgrass. Biological crust covers the soil in between perennial bunchgrasses and inhibits the seedling establishment of annual grasses like cheatgrass.
Cattle are also the primary agent that have destroyed riparian areas and wet meadows which are critical habitat to sage-grouse chicks. Livestock breaks down creekbanks which can lead to entrenchment of waterways and a lowering of water levels, which can then lead to a shrinkage of wet meadow habitat. Plus, by consuming streamside vegetation and reducing hiding cover, cattle expose sage grouse chicks to predators.
Fences constructed to control livestock constitute a significant source of mortality to sage grouse. Sage grouse are weak fliers and tend to fly close to the ground. In some studies, as much as 30 percent of sage-grouse populations are killed by collisions with fences.
Fences also act as "lookout posts" for avian predators like ravens.
In fact, why are their fences on public lands at all? Only one reason — to facilitate the exploitation of public resources for the benefit of private ranching interest.
The sage grouse requires habitat with a diverse plant community to provide shelter and food, especially a steady supply of insects to feed its young. Sage brush grouse also eat the leaves and flowers of soft, succulent forbs, as well as the insects that visit the plants. Unfortunately, livestock consumes many of the same forbs that sage grouse chicks require during the first couple of weeks of their lives, thus directly competing with sage grouse for an essential and critical food resource.
Water troughs designed to serve livestock also serve as breeding grounds for mosquitoes that spread West Nile Virus, which in some areas is also a significant source of sage grouse mortality.
In short, the BLM appears to be capitulating to private interests at the expense of the public's interest in healthy sagebrush ecosystems and healthy sage-grouse populations.
This article originally appeared in The Wildlife News.
George Wuerthner has worked as a biologist, wilderness ranger, and range conservationist for the federal government. More recently he has served as a university instructor, photography instructor, consulting biologist, and wildlife policy analyst. He is the Oregon director of the Western Watersheds Project. George appeared on Tommy's Treehuggers International show in 2010.
A San Diego County planning commissioner and former radio host and media personality, Tommy Hough works as an environmental consultant and communications professional, and is a California Democratic Party delegate and the co-founder and former president of San Diego County Democrats for Environmental Action.