After the Fire
What New Science Reveals About the Fate of Washington’s Sagebrush Country
On summer mornings in central Washington, the sagebrush seems timeless—silver‑green shrubs stretching to the horizon, punctuated by basalt cliffs carved by Ice Age floods. But in places like TNC’s Moses Coulee Preserves, part of one of the largest intact shrub‑steppe landscapes left in the state, we are learning that change is accelerating fast.
Wildfire, once an infrequent visitor in this dry ecosystem, is now arriving more often—and burning hotter. And new Washington State University (WSU) research from the preserve is helping TNC and partners understand what those fires leave behind: which species return, which struggle, and how invasive plants can lock landscapes into a cycle that makes recovery harder each time.
The findings are both sobering and hopeful. They show that while wildlife can persist after fire, the fate of sagebrush‑dependent birds and mammals increasingly hinges on what happens next—especially how quickly land managers can prevent invasive grasses from taking hold.
A Growing Threat in Sagebrush Country
Shrub‑steppe once covered nearly one-third of Washington state. Today, more than two‑thirds of that habitat has been lost to development, agriculture and fragmentation, leaving remaining sagebrush landscapes under increasing pressure. Climate change is compounding those stressors, bringing hotter summers and longer fire seasons to places that evolved with fire only once every few decades.
In Washington’s Columbia Basin, wildfire has become one of the most significant threats to sagebrush ecosystems—and to the diverse wildlife that depend on them. Species like sagebrush sparrows, Brewer’s sparrows and sage thrashers rely on dense shrub cover for nesting and protection. When fire removes that cover, it can take decades to return.
But fire doesn’t act alone.
After a blaze, invasive annual grasses such as cheatgrass often move in quickly. These grasses grow densely, dry out early in the summer and create fuels that are quick to burn and make future fires more likely—turning a one‑time disturbance into a recurring cycle.
Understanding how that cycle plays out on the ground was the goal of the multi‑year thesis study. From 2021 to 2024, WSU researchers surveyed sagebrush habitat across the Columbia Basin, including sites on and around The Nature Conservancy’s Moses Coulee Preserves, using wildlife cameras, bird point counts and vegetation surveys. They compared burned and unburned areas to understand how fire—and what follows it—affects wildlife.
The patterns were clear.
Unburned sites consistently supported more of the bird species that depend on sagebrush. Burned sites, meanwhile, showed lower numbers of those specialists—especially where invasive grasses had become established. In fact, the greater the cover of invasive annual grasses, the fewer of the studied species were found.
That finding is critical, because those same grasses increase the likelihood of future fires.
It creates a feedback loop, the research shows: fire removes shrubs, invasive grasses expand and the landscape becomes more fire‑prone—making it even harder for sagebrush and the wildlife that rely on it to recover.
Moses Coulee: Part of a Vast Sagebrush Landscape
Spanning across more than 24,000 acres, the Moses Coulee Preserves sit at the heart of one of Washington’s last remaining major shrub‑steppe corridors. With steep‑walled coulees, pothole lakes, dunes and expansive stretches of sagebrush, the preserves support a remarkable diversity of life—despite receiving little rainfall and enduring harsh temperatures.
Fires in recent years have burned large sections of the preserve, creating a patchwork of intact sagebrush habitat interspersed with burned areas and lands converted for agriculture. The new research helps highlight which parts of that patchwork matter most—and where restoration efforts can make the biggest difference for wildlife.
The research reinforces the importance of short‑term post‑fire management, especially eliminating invasive annual grasses before they dominate and crowd out native perennials.
It also informs long‑term fire resilience planning—helping land managers decide where to focus limited resources to maintain habitat connectivity across the broader Columbia Basin. The preserves are surrounded by lands managed by partners including the Washington Department of Natural Resources, Washington Department of Fish and Wildlife and the Bureau of Land Management—making collaboration and partnership essential.
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This special sagebrush landscape stretches outward across the American West into what ecologists call the Sagebrush Sea, one of North America’s most expansive and imperiled ecosystems. Across this vast, interconnected landscape, The Nature Conservancy and partners are working at scale to keep sagebrush country functioning as a living whole: protecting core habitats, restoring areas impacted by fire and invasive grasses, and strengthening the ecological connections that allow wildlife to move, adapt and persist in a changing climate.
By pairing place‑based stewardship at preserves like Moses Coulee with region‑wide science, partnerships and long‑term planning across the Columbia Basin and beyond, TNC is helping ensure that this majestic, often overlooked landscape remains resilient—for the future of the Sagebrush Sea and the plants, animals and people who call this special landscape home.
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