A version of this article was first published by our newsroom partner Grist. It has been reproduced here to focus on species in Greater Yellowstone and the West by Montana Free Press/Mountain Journal in collaboration with Grist and High Country News as part of the Report for America Local News Initiative.
The Endangered Species Act was passed in 1973 to address extinction. The policy set aside specific protections for imperiled species that extended beyond the organisms themselves. Under the ESA, it has long been as illegal to harm the habitat of a listed species as it is to harm the species itself.
That has now changed. The Trump administration redefined two key terms, regarding the ESA: “take” and “harm.” It’s a move the Stanford Woods Institute for the Environment calls a “deletion,” rather than a new definition. The changes mean it is no longer illegal to destroy an endangered species’ habitat.
The word “take” forms the heart of the ESA’s protective power, according to earlier MoJo reporting on an analysis by University of Montana law professor and ESA expert Sandra Zellmer. “Habitat modification is the primary reason for [ESA] listing,” Zellmer wrote in her 2026 American Bar Association journal paper. “If modifying habitat is no longer a ‘take,’ the ESA itself would be rendered incapable of satisfying Congress’ goal: ‘to halt and reverse the trend toward species extinction, whatever the cost.’”
Scientists widely recognize habitat loss as the single greatest threat to the planet’s biodiversity. Greater Yellowstone is one of the largest, nearly intact temperate-zone ecosystems in the world, and supports the greatest concentration of wildlife in the Lower 48. So what do these changes mean for the vulnerable species that call one of the most beloved ecosystems in the country home?
Mountain Journal’s team of reporters offers a glance into what’s at stake. – Ellis Juhlin
Wolverine
Sometimes called the “devil bear” or “woods devil,” the wolverine’s Latin name, Gulo gulo, translates to “glutton.” The roughly 20-50 pound high-elevation weasel cousins like to eat. They scavenge prey hunted by larger predators, kill animals of their own and supplement meat with roots and berries.
They’re also Greater Yellowstone’s rarest mammal. An estimated 35 wolverines remain in the entirety of the Northern Rockies, including Greater Yellowstone, according to the U.S. Fish and Wildlife Service. In studies from 2006-2009, researchers documented just seven wolverines in Yellowstone National Park and adjacent national forests.
Wolverines occasionally get snagged accidentally in traps and the growing popularity of winter recreation like snowmobiling and backcountry skiing can fragment their habitat as well. The changing climate, however, is expected to shrink the species’ already small range by 63 percent in the next 75 years.
“Other threats are minor in comparison to the driving primary threat of climate change,” FWS wrote in a status assessment of the species.
The debate over how to protect the species has been long and contentious. They were first petitioned to be added to the endangered species list more than 30 years ago. They finally received threatened species protections under the ESA in 2023. Conservative lawmakers in Montana pushed back against the federal decision and months later the state of Montana filed intent to sue.
Now, with new federal leadership at the helm of FWS, the agency has missed its deadline to establish critical habitat for the species. Earlier this year, conservation groups sued, saying that federally protected critical habitat makes a species more than twice as likely to recover.
“In the face of climate change, it’s crucial to protect the rugged, snowy areas that the wolverine needs to survive,” Andrea Zaccardi, carnivore conservation legal director at the Center for Biological Diversity, said in a statement. – Nick Mott
Grizzly Bear
The grizzly was the eighth animal to be listed under the Endangered Species Act after it was passed in 1973. Before Lewis and Clark made their Voyage of Discovery at the turn of the 19th century, an estimated 50,000 grizzly bears roamed the western United States between Canada and Mexico. By the time they were listed in 1975, about 600 remained.
Most were killed in conflict with farmers and ranchers through the U.S. Department of Agriculture’s predator removal programs. Most of the remaining grizzlies enjoyed protection inside Yellowstone and Glacier national parks, where they grew dependent on tourist garbage as a food source.
A combination of National Park Service policy changes and mauling incidents ramped up efforts to control grizzly behavior in the 1960s. But instead of reducing conflicts, the new policies resulted in the deaths of at least 120 Yellowstone grizzlies in 1972 alone.
In 1982, the Interagency Grizzly Bear Committee convened federal, state and academic wildlife experts to develop a recovery plan for the grizzly bear. Much of its work concerned identifying what food sources grizzlies depended on and what kinds of habitat provided those foods. Its researchers also teased out the kinds of places they need to hibernate, raise cubs and establish territories.
Those places, known as “critical habitat” under the bears’ recovery plan, are also the most common points of conflict in bear management. Recent lawsuits have pitted grizzly advocates against federal agencies over projects that increased road access, allowed cattle grazing, or encouraged trapping in grizzly areas.
Interior Department officials under the Biden Administration reinforced ESA protections for grizzly bears just before Donald Trump began his second term as president in 2025. Trump’s Interior officials plan to rewrite those rules, and in July announced their intention to return grizzlies to state control. – Robert Chaney
Western Bumble Bee
Montana has more species of bumble bee than any other state.
The western bumble bee in particular once ranged from Alaska to California, and into Montana and Wyoming. The bees are specifically adapted to the diverse, mountainous ecosystem of the Northern Rockies. In early spring, they can raise their body temperatures by as much as 60 degrees to visit flowers when it’s just too cold for other species of insects.
The fuzzy, striped bee is still present in Greater Yellowstone, but scientists estimate the species has declined by 93 percent between 1998 and 2018. According to the U.S. Geological Survey, a large culprit is the use of neonicotinoids, a potent insecticide that gained prevalence in the 1990s. At the same time, the bees are experiencing habitat fragmentation and the spread of pathogens from domestic honey bees.
In 2016, the Fish and Wildlife Service found that the western bumble bee may deserve Endangered Species Act protections. But the agency has since pushed back its timeline for next steps in the listing process through at least 2029.
While only two species of bees are federally protected, insects and invertebrates make up nearly half of the endangered species list. Bolt said bumble bees in particular play a crucial role in food production, carbon sequestration and even cleaning water. He called the bumble bee the “canary in the cornfield.”
“You can almost guarantee that if things are harming large, visible insects like the western bumble bee, those impacts are happening on many other species that no one’s really taken the time to look at,” said Clay Bolt, manager of pollinator conservation with the World Wildlife Fund. “Without these species, we’d be in a world of hurt.” – Nick Mott
Whitebark Pine
Plants, like animals, can also receive Endangered Species Act protections.
Take, for example, the whitebark pine. These slow-growing, long-living trees are the backbone of their ecosystem. They thrive in deep snow and the extreme wind of rocky high-alpine ridgelines where little else survives. Their roots prevent erosion, and the shade from their trunks and branches holds snow on the landscape longer, improving soil moisture and slowing runoff.
Whitebark’s nutrient-dense seeds also provide food for everything from Clark’s nutcrackers to grizzly bears at high elevation areas where food can be in short supply. Whitebarks have declined by as much as 85% across the Greater Yellowstone Ecosystem, and face similarly precipitous declines across their range in western North America.
A deadly fungal infection, the droughts and extreme fire seasons that come with climate change, and pine beetle infestations have all contributed to whitebark declines, prompting FWS to list them under the Endangered Species Act in 2022. “For some regions, the window of opportunity is closing for whitebark pine restoration,” according to the Missoula-based Whitebark Pine Foundation. “We urge that management strategies be devised and implemented as quickly as possible.”
Under the Trump administration’s recent changes to the Endangered Species Act, it’s now only illegal to cut down a whitebark pine tree, but not to destroy the places where it lives.
Nearly all the whitebark pine range in the Lower 48 states exists on federal public lands. National parks, wilderness areas and national forests make up 98% of the tree’s habitat. Ongoing changes to public land management, in addition to changes to the ESA, further threaten whitebark survival. – Ellis Juhlin
Canada Lynx
A Canada lynx weighs about the same as a cocker spaniel, but has far more impact on both the legal and ecological landscape.
Few people ever see the 20-ish-pound wild cat with distinctive tufts topping its ears. But it regularly appears in lawsuits challenging U.S. Forest Service logging projects, due to its specific habitat needs. The lynx mainly eats snowshoe hares, which it finds in mature conifer forests. So the prime threat to its survival isn’t hunting or trapping, but loss of tree cover through logging or development.
Canada lynx achieved “threatened” ESA status in 2000 after years of lawsuits against the federal government seeking to protect the species. Part of the challenge was establishing a count of how many lynx were on the landscape. The 2012 edition of the authoritative Mammals of Montana notes “detailed estimates for the statewide population are not available” but concluded between 350 and 500 animals might be present. More current calculations put the population in the Rocky Mountain regions of Montana, Idaho, Washington and Wyoming at around 1,000 animals.
Uncertainty about the number and whereabouts of Canada lynx has led to numerous efforts to revise its critical habitat designation. The most recent occurred in July, when Trump administration officials proposed reducing the 2014 area by about 32 percent to 14,030 square miles of Montana, Idaho, Colorado and Washington. A more controversial attempt took place in 2009, when an Interior official in the George W. Bush administration was found to have illegally reduced lynx habitat from 39,000 square miles to just 1,841 at the request of timber interests.
– Robert Chaney
Arctic Grayling
Montana is home to the last native population of river-dwelling Arctic grayling in the Lower 48. These salmonids, known for the massive, colorful dorsal fin on their backs, are not currently listed under the Endangered Species Act, but has been considered as a viable candidate in recent years.
Grayling rely on cold water and can die without it. Overfishing, nonnative competition and increasing drought have all contributed to grayling declines. Wildlife advocacy groups like the Center for Biological Diversity have said grayling stand on the brink of extinction without an ESA listing.
In Montana’s Big Hole Valley, landowners have spearheaded a multidecade, voluntary water-conservation agreement to keep water levels sustainable for grayling. The Big Hole Watershed Committee touts the efforts as a success, saying they’re crucial to avoid federal overreach on private land, where 90% of grayling habitat exists. At the same time, a legal battle has been raging for years over whether or not the species should make the endangered list. In 2020, FWS ruled that grayling did not warrant an ESA listing.
Most recently, in 2024 a federal district court in Montana found that FWS needed to reconsider that 2020 decision to not list grayling. The agency has until February 2027 to conduct its Species Status Assessment. Even if listed, considering the Trump administration’s changes to the ESA, grayling could be harmed or water could be removed from the river system harming the fish’s habitat. – Ellis Juhlin
