Rangelands, those wide-open spaces dominated by grasses, shrubs and sagebrush are rapidly declining across the United States. Now, for the first time, researchers at Montana State University have created a comprehensive inventory of the wildlife that rely on these ecosystems, identifying a total of 1,066 species.
Published in January in the journal Rangeland Ecology and Management, the study offers the most complete inventory yet, intended to give land managers, policymakers and outdoor enthusiasts a clear picture of which species rely on this habitat, a necessary baseline for conservation and management.
To understand the full scope of rangeland wildlife, the research team, led by MSU Professor Lance McNew, seven graduate students and three undergraduate students in the school’s Department of Animal and Range Sciences, analyzed species across the 21 states that contain rangeland habitat. In the Greater Yellowstone Ecosystem, an estimated 70 percent of Montana, 85 percent of Wyoming, and roughly 55 percent of Idaho are made up of rangeland.
The paper is the result of a simple question asked by McNew while working on the introduction to a book titled Rangeland Wildlife Ecology and Conservation: How many wildlife species require rangeland habitats in North America?
“Surprisingly, that search returned no clear answer; results in the literature varied, and most numbers provided could not be vetted due to a general lack of descriptive methods,” McNew told Mountain Journal. “I was not that surprised to learn that most of our wildlife species in the West are associated with or depend on rangelands. What surprised me was that no complete inventory of rangeland wildlife had previously been produced.”
Rangelands are the most widespread and most imperiled ecosystems on the planet, according to McNew. North America has witnessed a loss of 50 to 98 percent of native grasslands at a rate of several million acres annually since the early 1990s, and declining shrublands like sagebrush steppe not far behind.
“These systems deliver innumerable social, economic and ecological services that millions of people in the West depend on,” he said. “Rangeland wildlife communities are integral parts, not just the benefactors, of functional rangelands.”
The MSU team’s research involved categorizing each species by how closely its survival depends on rangeland ecosystems, using factors like nesting behavior, breeding needs, diet and other ecological requirements. The group also identified which species already face significant conservation risks. Of the 1,066 species documented, 33 are listed as endangered, near threatened, or vulnerable by the International Union for the Conservation of Nature.
“Rangeland wildlife communities are integral parts, not just the benefactors, of functional rangelands.”
Lance Mcnew, professor, wildlife habitat ecology, montana state university
This growing list of at-risk species highlights the potential impact of increased land-use changes. McNew said the biggest threat to rangeland habitats everywhere, including the GYE, is conversion to other land types through cultivation, woody encroachment and human development.
McNew hopes the study will help tell the story of just how widespread and important rangeland habitats of the western U.S. are, adding that one of the most rewarding aspects of the project wasn’t just the scientific findings, it was the people behind the effort.
“I’m proud of the applied scientific and conservation impact of the work, but I’m even more proud that the paper was led and conducted by 10 graduate and undergraduate students. One of the best things about my job is being able to work with incredibly talented and enthusiastic students.”
