If you pay attention to livestock grazing issues on public lands, you invariably will see research promoting cattle grazing as the magic elixir that can repair damaged riparian areas, eliminate cheatgrass and other weeds, reduce wildfires, increase soil carbon storage, and improve habitat for endangered species like sage grouse.
If you think this is too good to be true, or you are someone who spends any time out on the public rangelands, you know this isn’t true. But that doesn’t stop the range promotion industry from making such assertions.
In general, livestock grazing reduces biodiversity, degrades rangelands, and is a major factor in sage grouse endangerment. However, one can focus on a particular subset of the grazing issue and make it seem like livestock grazing is a plus to rangeland ecosystems, much as the timber industry promotes logging as a mechanism for forest health.
In fact, we live behind a Bovine Curtain where government agencies, researchers in Range Departments, and livestock promoters like the Nature Conservancy usually ignore anything negative about livestock grazing.
As with many of these studies, the truth lies in the details. A good example is a recent widely distributed article Stepping Lightly in the Sage.
The title itself is misleading. Cattle trample the land; they don’t step lightly.
The main summary suggests that “Researchers Learn Moderate Grazing Has No Effect on Sage Grouse Nest Success.”
The news story outlines a 10-year study, funded in part by the Idaho legislature, the Bureau of Land Managmeent (BLM), and Idaho Fish and Game. The study was led by University of Idaho Professor Courtney Conway, leader of the Idaho Cooperative Fish & Wildlife Research Unit in the Department of Forest, Rangeland, and Fire Sciences in the College of Natural Resources. and Professor Karen Launchbaugh, the director of the Rangeland Center has some serious limitations.
Remember to follow the money—it determines what questions are asked and what results are reported. Range departments, as well as related disciplines like wildlife biology departments, depend on funding from state legislatures and other sources that want to promote the ranching industry. The Idaho legislature is largely ranchers. This funding source often limits the kinds of questions that are asked, often narrowly defined, so that the “big picture” perspective is lost.
I don’t want to imply that either of these scientists purposely fudged the results, but there are reasons to be wary of their conclusions. Remember that none of this research was published in peer-reviewed journals.
According to the news report, the researchers found that cows sharing nesting habitat with grouse on federal lands do not influence nest success of greater sage grouse if grazing intensity is kept at current levels.
The phrase “current levels” in reference to the study is a critical point. The ranchers involved in the study generally graze at a lower intensity than the typical public lands rancher.
To quote from the article: “Master’s student Nolan Helmstetter, whose research focused on sage grouse nest predators, found that coyotes were the primary nest predators on five study sites and higher shrub canopy cover decreases the probability of nest predation by coyotes. But whether cattle grazed the area did not affect predation.”
The problem with this characterization is that the level of grazing pressure was very light and not representative of the typical situation on public lands.
Overall, the livestock utilization in the study (i.e., vegetation removed) was approximately 19% of available forage, which is significantly lower than the typical 50-60% permitted on public lands. In many cases, livestock often remove even more than 50-60% of many public land allotments. This is more than 3 times the intensity of grazing involved on this study.
Therefore, nesting success was higher, not surprisingly, since removing more vegetation by grazing livestock enables sage grouse predators, particularly avian predators, to locate nests.
However, another problem with using “nest success” as an overall indicator of livestock compatibility with sage grouse survival is that recruitment into adult or breeding birds is by far the most critical factor.
You may have more eggs that hatch, but what happens after they hatch determines the overall sage grouse population. There are many reasons why livestock grazing reduces overall sage grouse survival, which I will address later.
Beyond the issue of “nest success,” another alleged benefit of livestock grazing is that bovines on the land result in more insects, especially in the spring, when chicks rely on bugs for food. Research shows that more than 90% of the diet of one to four-week-old chicks comprises arthropods.
To quote from the article: ”Spring grazing resulted in a greater number of insects, a greater variety of insects, and the insects found under the spring grazing treatment generally are bigger, which could provide more food for sage grouse,” said entomologist Grace Overlie, a U of I master’s student on the project.
This claim is problematic for several reasons. First, the study used “pitfall” traps to gather insects. Pitfall traps gather more insects where there is less vegetation, which, of course, results from livestock grazing.
Pitfall traps also reduce insect predators that fall into traps. Bycatch of lizards, shrews, and mice that prey on insects can lead to higher insect counts because there is a reduction in insect predation.
Furthermore, the grouping of insects was very broad. Even if there are “more insects”, they are not necessarily insects sage grouse chicks use.
Another issue is insect biomass. The study did not identify insects to species. For example, you may capture more tiny pavement ants; even if abundant, they may not contribute much to the sage grouse chick’s overall diet. So, merely identifying major groups of insects like “ants” doesn’t necessarily tell you what insects are consumed by sage grouse.
Forbs are flowers that sage grouse chicks consume. But not all forbs are equally valuable for sage grouse chicks. Photo George Wuerthner
This is very similar to the situation one often hears about livestock and forbs (another name for flowers) abundance. Sage grouse chicks only consume specific flowers. So abundant flowering plants doesn’t necessarily translate into food for chicks. For example, fiddlehead, which cattle tends to ignore often increase with cattle grazing. Fiddlehead is not a significant food item for sage grouse chicks either. So, having a lot of fiddleheads does not mean sage chick food is abundant.
Another issue is that Conway is a biostatistician and not an insect expert.
The study’s narrow parameters hide the bigger picture. Even if the researchers’ above assertions that spring grazing had little impact on sage grouse are true, it doesn’t nullify the fact that overall livestock production harms sage grouse.
For instance, the numerous fences that crisscross public lands to facilitate cattle production are a major source of mortality for sage grouse. In some cases, up to 30% of the mortality for adult sage grouse results from collisions with fences.
Fences also provide perches for avian predators like ravens, who can spot where sage grouse nests are located.
Cattle, in particular, are a major source of riparian damage across the West. Unlike the characterization in the title, cattle trample these wetlands, breaking down the banks of streams and consuming the streamside vegetation. Sage grouse chicks utilize plants in riparian areas and wetlands in their first month or so of life.
Cattle trampling of biocrusts, the lichens, bacteria, and mosses that cover the soil between grass plants in arid landscapes. Biocrusts prevent soil erosion, transfer nitrogen, an essential element for plant growth, to the soil, and avoid colonization by weeds like cheatgrass, an annual grass that is fire-prone and one of the major factors in the spread of range fires. The increase in range fires is one of the major factors leading to the loss of sage steppe ecosystems around the West.
Of course, as the study researchers implied, loss of vegetative cover due to livestock grazing is a major factor in predation losses. Thick vegetation hides nests, chicks, and adults. Since livestock grazing, particularly in the more arid parts of the West, is a major factor in vegetation reduction, it is one of the leading causes of sage grouse decline.
Another factor seldom mentioned is that many of the valley bottoms around the West have been converted from native vegetation (usually sagebrush steppe) into irrigated hay fields for cattle feed. Loss of these sage bottomlands have been significantly reduced much of the good sage grouse habitat.
I could go on with other reasons why livestock production is a critical factor in the decline of sage grouse, but suffice it to say that it is disingenuous to suggest that livestock production is somehow compatible with sage grouse survival.
The ultimate solution for sage grouse recovery is not more propaganda about how livestock production and sage grouse survival are compatible but to reduce or eliminate livestock from public lands. One means of accomplishing this is by closing allotments by federal agencies.
However given the political power of the ranching industry another often more acceptable means is through the Voluntary Grazing Permit Retirement Act. Under the Act, permittees would receive a one-time payment to terminate their use of a federal grazing allotment, with the site permanently retired from any future grazing.
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