George Wuerthner: BLM is attacking juniper to help cows, not sage grouse
This Aug. 15, 2019 photo shows dozens of juniper trees cut down as part of a giant project to remove junipers encroaching on sagebrush habitat needed by imperiled sage grouse in southwestern Idaho. The Bruneau-Owyhee Sage-Grouse Habitat Project aims to remove junipers on 965 square miles (2,500 square kilometers) of state and federal land in Owyhee County. (AP Photo/Keith Ridler)
The Bureau of Land Management (BLM) has launched a massive juniper removal project in Idaho and plans to expand removal in Grand Staircase Escalante National Monument in Utah as well.
Juniper is a common native species that grows in arid landscapes along with sagebrush and grasses.
The rationale given for the juniper removal is to improve sage grouse habitat. However, that is a red herring. The real reason is to create more forage for private livestock.
The BLM and the livestock industry argue that juniper deforestation will benefit sage grouse because they assert juniper is occasionally used as perches by avian predators.
There are no studies that I’m aware of that demonstrate that use of juniper as perches by sage grouse raptor predators is common.
Ravens, another bird that occasionally preys on nests and eggs, will use scattered juniper for perches. However, this does not appear to be common.
It is accurate to suggest that sage grouse avoid areas with any kind of woodland or trees, therefore removal may increase potential sage grouse habitat in some places. However, is juniper a major impediment to sage grouse survival?
While there is little evidence that juniper are used by birds of prey like golden eagles, there are many observations of eagles using fence posts for perching. Why are there miles of fences across the sagebrush sea? Livestock production.
Furthermore up to 30% of the mortality of sage grouse in some areas is due to collision with fences. Thus, if the BLM were genuinely concerned about the future of sage grouse, it would be eliminating or decreasing fences, not juniper.
Plus, the bulk of BLM lands are in poor to fair condition, meaning there is little hiding cover for sage grouse. It’s possible that removing or reducing livestock grazing might lead to much higher sage grouse survival, even in the face of bird of prey if there were enough grass to hide the grouse from predators.
According to the BLM, juniper is “invading” sagebrush ecosystems due to “fire suppression.”
The BLM asserts that range fires historically were frequent and low severity, burning sagebrush ecosystems every 10-25 years. Such recurrent blazes would logically preclude the establishment of juniper except on rocky sites and other areas where a fire was excluded.
If fire were that frequent, It would also eliminate most sagebrush since they typically burn on a 50-400 year fire rotation.
In a more recent review of juniper fire ecology, the researchers concluded that “spreading, low-severity surface fires were likely not common.” Instead of low severity fires, the researchers found that “nearly all observed fires since EuroAmerican settlement in these woodlands were high-severity fires” and often centuries apart.
For instance, a survey conducted in Dinosaur National Monument found that juniper fire rotations were 550 years. Similar long fire rotations of 400 years in one case, 480 years in the other have been reported.
Therefore, much of what is viewed as juniper “expansion” may be recolonization after high severity fires.
Worse for sage grouse, juniper removal, and the disturbance that comes with it can promote the establishment and spread of cheatgrass. The highly flammable cheatgrass by shortening the regular fire rotation and burning up sagebrush habitat is a far greater threat to sage grouse survival than the presence of juniper.
To the degree, that juniper removal might, in some cases, benefit sage grouse is a distraction or smoke screen. The more significant factors contributing to sage grouse declines, which include the cumulative impacts of livestock production, continued to be ignored by the BLM.
George Wuerthner is a former BLM botanist and and ecologist who has published several books on fire ecology, including “Wildfire: A Century of Failed Forest Policy.”