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Cattle Queen
Livestock grazing is bad for the environment concludes range scientist Joy Belsky, who earlier this year published a paper rounding up the last decade of research on livestock grazing in the western United States.
Contrary to a prevously reported unpublished study that showed no effects from grazing on certain springs in the Central Valley, Belsky's paper surveyed virtually all the ecological aspects of livestock grazing in the western United States, from effects on ground-nesting birds to water quality. The news was overwhelmingly bad. Livestock grazing has damaged 80% of the streams and rivers west of the Mississippi, according to a U.S. Department of Interior report that Belsky unearthed. Another report by the U.S. Environmental Protection Agency indicated that riparian areas throughout much of the West are in "their worst condition in history."
Belsky's report, in the Journal of Soil and Conservation Science, summarizes the results of 143 scientific papers on the effects of livestock grazing. Although Belsky works for a conservation group, the Oregon Natural Desert Association, she said she made an extra effort to seek out papers that would buttress claims by grazing supporters. These include the idea that the hooves of a 1,000-pound animal act like Rototillers, helping promote plant growth by churning up soil. Au contraire, said Belsky.
"I was really interested in looking at some of these claims," Belsky said. "We looked very hard for papers that showed benefits and couldn't find any. There were papers that showed no effects. Usually the authors themselves pointed out that something had gone wrong, either with the research methodology or an unusual event, like a flood. Every paper that cited a positive or neutral effect, we cited."
Using peer-reviewed scientific publications as well as government documents, Belsky's paper, catchily titled "Survey of Livestock Influences on Stream and Riparian Ecosystems in the Western United States," paints a bleak picture of a starkly beautiful but desperately arid region where water and wildlife are synonymous. For instance, Robert Ohmart, an ornithologist at Arizona State University, estimated that 60-70% of Western bird species depend on the cottonwood-willow habitat found along the banks of western rivers.
In the highly arid states of Arizona and New Mexico, 80% of wildlife species are dependent on this habitat, the most productive in North America in terms of biodiversity, but also the most endangered. In Arizona, which Ohmart studied extensively, only three percent, or 10,000-11,000 acres, of willow-cottonwood habitat remains. Given this data, it's easy to understand why the overwhelming majority of Western salmon and trout are threatened or endangered and why native and neotropical migratory birds are losing ground fast.
Yet Belsky's paper also cited statistics indicating that the number of cattle in the western United States doubled betweeen 1940 and 1990. Obviously, that's not true in the urbanized San Francisco Bay Area, where conservationists sometimes make alliances with ranchers to keep out subdivisions. But as the scientific evidence on the ecologically destructive effects of grazing mounts, it casts doubt on whether the cowboy really can save us from ourselves.
Why is the cowboy myth is so resilient? Belsky says she leaves that kind of theorizing to the softer sciences, like history or political philosophy. Her focus is on something more tangible: the disturbing possibility that western wildlife may not outlast America's romance with the cowboy.
Contact: Joy Belsky (503)228 9720
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