In the high-altitude wilds of North America, two iconic landscapes—one bustling with the frantic energy of tiny pikas, the other shaped by the slow, dramatic retreat of ancient ice—are sending out distress signals. Recent scientific studies and local accounts from the Rocky Mountains and Juneau, Alaska, reveal how climate change is not just a distant threat but a force already reshaping ecosystems, cultures, and economies.
On the wind-scoured talus slopes above Colorado’s treeline, American pikas have long charmed hikers with their sharp chirps and frantic foraging. These small, rabbit-like mammals have survived for thousands of years by hoarding flowers and grasses, darting between rocks to escape predators and, more crucially, the heat. But as temperatures climb, their finely tuned metabolisms are becoming a liability rather than an asset. According to a new study published on December 4, 2025, in Arctic, Antarctic, and Alpine Research and reported by The Colorado Sun, juvenile pika populations on Niwot Ridge, just south of Rocky Mountain National Park, have declined by a staggering 50 percent.
“Our findings certainly suggest the need to consider that pika populations might soon be lost from some locations in the southern Rockies,” the study warns. The culprit? Temperatures above 76 degrees Fahrenheit. Pikas, it turns out, can’t survive for more than a few hours in such heat. When the mercury climbs, these creatures retreat into the stable, cool microclimates between boulders—places that, as University of Colorado researcher Chris Ray puts it, are “more stable than the temperature in one of the laboratories here at CU.”
This evolutionary adaptation, which allows pikas to weather brutal winters without hibernating, now traps them in a deadly paradox. Their thick fur and high resting body temperature keep them alive in the cold but make them exquisitely vulnerable to summer heat. As Ray explained, “during the summertime, they’re very sensitive to heat, meaning they can’t actually survive for a few hours at anywhere above about 76 degrees.”
The study’s demographic data is stark: aging adults are plentiful, but healthy juveniles are scarce, signaling a collapse in recruitment—the process by which young pikas strike out to claim new territories. “Juveniles are not coming in and claiming these empty territories,” Ray said in a December 3 interview. “It looks, unfortunately, like the demographic data is supporting our dire prediction for Rocky Mountain National Park.”
Efforts to adapt, whether by evolving thinner fur or shifting to nocturnal habits, are all but impossible for the pika. “Evolutionary adaptation for pikas would take thousands of generations, if not longer,” Ray noted. And even if a pika were born with thinner fur, it would likely freeze during the frigid mountain nights. Becoming nocturnal would require a complete overhaul of their physiology, including new eye structures—an evolutionary leap too far for these creatures.
Adding to the concern, temperature sensors placed deep within pika talus habitats show that these microclimates are warming even faster than the surrounding air. “At one place on Niwot Ridge, we see that the temperatures in that microclimate have actually gone up more than the temperatures in the free air,” Ray revealed. “That was astounding to us.”
While Ray admits to worrying about the fate of these “incredible creatures that survive incredibly harsh conditions,” she remains committed to studying them. “What makes them be able to survive the conditions that we perceive as harsh, cold conditions, is precisely what makes them vulnerable to the warming conditions, and I’m just more and more interested in what’s going to happen. So I’ll just keep studying this for the rest of my life.”
Far to the north, another drama is unfolding on the outskirts of Juneau, Alaska. On November 15, 2025, the face of the Mendenhall Glacier—known to the Tlingit people as Áakʼw Tʼáak Sítʼ—separated from Mendenhall Lake for the first time. This event, chronicled by the Juneau Independent, marks the glacier’s transition from a lake-calving glacier to a mountain glacier. Since its Little Ice Age maximum around 1760, the Mendenhall has retreated more than four kilometers and is now losing about 48 meters each year.
The glacier’s rapid retreat was featured in a global report released in October 2025, authored by 160 scientists from 23 countries. The report uses the Mendenhall as a case study of climate change tipping points, warning that the Juneau Icefield—the fifth-largest in North America—could reach a threshold where melting accelerates abruptly and irreversibly. The risk is heightened as the world edges closer to exceeding 1.5 degrees Celsius of global warming, a benchmark scientists now expect to be surpassed within the next decade.
For Juneau residents, the consequences are immediate and personal. The glacier’s retreat has increased the risk of glacial lake outburst floods, with the Mendenhall River cresting at record levels each August due to releases from Suicide Basin. According to Donovan Dennis, a scientist at the Potsdam Institute for Climate Impact Research and co-lead of the Mendenhall case study, “Juneau, as we wrote in the case study, contributes very, very little to climate change as a community. It doesn’t have these major factories, major electrical production facilities that are putting carbon into the atmosphere at a rate that’s alarming or even globally significant.” Yet, he added, “Juneau is feeling the impacts of climate change, as are other local communities, through events such as record glacial flooding.”
The glacier’s disappearance is also a profound cultural loss for the Tlingit people, who have stewarded the land for thousands of years. Anthropologist Judith Dax̱ootsú Ramos, a coauthor of the study, explained, “We’re very attached to the environment where we believe that everything has a spirit.” The report notes that rapid deglaciation “disrupts the relationship between Indigenous communities, glaciers and glacial landscapes, depriving future generations of this component of their identity and history, which are inseparable from the land.”
Economic impacts are looming as well. The Mendenhall Glacier attracts about 700,000 visitors annually, and projections suggest it will no longer be visible from the popular visitor center by 2050. The U.S. Forest Service is already exploring new viewing locations, but the case study cautions that expanding facilities for a vanishing glacier may “defy reality.” The loss of the glacier viewshed has already led to declining tourism at other Alaskan sites, like the Begich, Boggs Visitor Center near Portage Glacier.
As these two stories unfold—pikas vanishing from Colorado’s high country and glaciers receding from Alaska’s valleys—they highlight a shared truth: climate change is not a distant or abstract threat. It is altering landscapes, upending ecosystems, and reshaping the ways in which people connect to the land. The scientists, Indigenous leaders, and local communities grappling with these changes are calling not just for adaptation, but for solidarity, proactive governance, and a renewed respect for both nature and traditional knowledge. The future of these fragile places depends on it.
