University of Colorado Boulder: Scientists call for ‘Western Rewilding Network’ to support wolf, beaver populations, improve biodiversity on public lands

Managing federal lands in ways that better support wolf and beaver populations could help re-establish a host of important ecological processes across the West, according to a group of 20 scientists calling for the creation of a Western Rewilding Network.

In a paper published today in BioScience, “Rewilding the American West,” authors from CU Boulder, Oregon State University and several other institutions suggest using nearly 193,000 square miles (500,000 square kilometers) of federal lands in 11 states to establish a contiguous network based on potential habitat for the gray wolf and American beaver. Supporting those species through management changes on federal land would help control elk populations, support tree growth, boost biodiversity, improve water quality, increase carbon sequestration and restore riparian habitats, they said.

“While most people know what a beaver or a wolf is, they may not understand their critical ecological roles and the ecosystem services they provide. By simply letting beavers and wolves do what they evolved to do, they can restore ecological integrity to an entire landscape,” said Joanna Lambert, co-author on the paper and professor of environmental studies at CU Boulder.


The proposed network would include federal lands in Oregon, Washington, California, Nevada, Idaho, Montana, Wyoming, Colorado, Arizona, New Mexico and Utah. Proposed management changes include removing livestock grazing on up to a third of federal allotments, and implementing an economically and socially just federal compensation program for those who give up their grazing permits. The proposal also supports President Biden’s America the Beautiful plan, which aims to conserve 30% of U.S. land and water by 2030.

“It’s an ambitious idea, but the American West is going through an unprecedented period of converging crises including extended drought and water scarcity, extreme heat waves, massive fires and loss of biodiversity,” said William Ripple, co-lead author and distinguished professor of ecology in the OSU College of Forestry.

Colorado, Lambert notes, is already implementing a major rewilding proposal, as residents passed Proposition 114 in 2020 to restore wild gray wolves to their native habitat in public lands on the western slope. Lambert has been very active in this initiative as a science advisor for the past several years.

“Colorado serves as a model for how to implement the rewilding measures proposed by this study,” said Lambert, also an affiliate professor of ecology and evolutionary biology at CU Boulder.

Gray wolves were hunted to near extinction in the West but were reintroduced to parts of the northern Rocky Mountains and the Southwest starting in the 1990s through measures made possible by the Endangered Species Act.

The gray wolf’s current range is only about 14% of its historical range, however, and today there might only be 3,500 wolves across the entire West—compared to tens of thousands previously, according to co-lead author Christopher Wolf, a postdoctoral scholar in the OSU College of Forestry.

Wolf restoration offers significant ecological benefits by helping to naturally control native ungulates such as elk, according to the authors. They say wolves facilitate regrowth of vegetation species such as aspen, and diverse plant and animal communities, which are declining in the West.

Beaver populations, once robust across the West, declined roughly 90% after settler colonialism and are now nonexistent in many streams. By felling trees and shrubs and constructing dams, beavers enrich fish habitat, increase water and sediment retention, maintain water flows during drought, improve water quality, increase carbon sequestration and generally improve habitat for riparian plant and animal species.

Riparian areas occupy less than 2% of the land in the West but provide habitat for up to 70% of wildlife species, making beaver restoration a cost-effective and efficient way to repair degraded riparian areas and boost biodiversity, according to co-author Robert Beschta, professor emeritus in the OSU College of Forestry.

“This paper and the rewilding message that it carries reminds us that we still have so much wilderness left,” said Lambert. “This study demonstrates in concrete and explicit terms how we can go about implementing action to keep it.”