Bad Hare Day
Glacier National Park’s snowshoe hares cope with a changing climate as they catch themselves dressed for the wrong occasion.
In the northernmost reaches of Montana lives a world-class athlete. If you crossed paths with this creature on a snowshoe in Glacier National Park, you probably wouldn’t guess it’s capable of outrunning an avalanche. Its tiny nose twitches. The images that come to mind are more Easter bunny than Usain Bolt.
That is, until the snowshoe hare decides you’ve gotten too close and takes off. Its massive back feet seemingly float across the snow, its tiny figure disappearing in a heartbeat—it can move up to 27 mph, just under the human speed record. You glance down at your clunky snowshoes in awe, remembering how long it took you to slog through the same snow.
When University of Montana researcher and professor Scott Mills heads out into the same forests in early spring, he’s greeted by an unusual sight. Warming climate has caused the snowfall that normally covers northern Montana this time of year to disappear. In the middle of this brown landscape sits a snowshoe hare. It doesn’t move a muscle; it knows its camouflage will keep it hidden from sight. The only problem? Its fur is still pure white. Mills walks right up to it. It’s almost comical.
The mismatched snowshoe hare is a visual cue of climate change in Glacier National Park. Earlier snowmelt, receding glaciers, unprecedented wildfires and devastating beetle kill put the Crown of the Continent at the frontlines of a battle the entire world is fighting—and if nothing changes, Glacier’s snowshoe hare population and the rest of the delicate ecosystem intertwined with it, might be the first casualties.
The Lynx Connection
A snowshoe hare’s coat changes each winter to help it blend into its snowy environment. If you were to hike through the conifer forests on the eastern side of Glacier National Park, you might not even spot it against the snow. It’s not the presence of snow that triggers the change—it’s the presence of sunlight. When days start getting longer, the hare’s genetics trigger the color change back to summer brown. But today, the snow is melting long before the days begin to lengthen, turning the hares into easy picking as they’re dressed for the wrong occasion.
“Climate change is affecting many species,” says Mills, “but those experiencing seasonal color mismatch are such a visual representation of those effects. It doesn’t matter if you’re in Mongolia or Montana, the average snow season is shortening worldwide.”
It can be a domino effect when a species like the snowshoe hare can’t adapt to its changing environment. For instance, the snowshoe hare and its primary predator, the Canadian lynx, have spent their entire existence perfecting their adaptations to the boreal spruce and fir forests, like those on Glacier’s eastern side. A snowshoe hare is most at home here, munching on conifer pine needles while the ghost-like lynx expertly stalks it. In the winters, 98% of a Canadian lynx’s diet is snowshoe hare. In these snowy forests, the creatures have found their niche. Their athleticism in the snow gives the two species an edge on other creatures in the region, but it also makes them extremely sensitive to the effects of climate change.
The snowshoe hare population is intrinsically linked to that of the lynx, as well as other predators that rely on the hares as a food source like great-horned owls and northern goshawks. If snowshoe hare populations fluctuate or decline, so do
those of its predators.
When Glaciers Disappear
It’s not just the snowshoe hare that’s being impacted by climate change. There are few places that its effects are as apparent as Glacier National Park. A 2017 time-series analysis of the park’s iconic glaciers by the United States Geological Survey shows shocking contrasts between the park of 50 years ago and today. Some glaciers have
shrunk by 85%.
This is largely because of warming temperatures. Since 1900, Glacier’s mean annual temperature has increased by 2.39°F, which is 1.8 times the global increase. Compared to the mid-70s, current snow is melting—and staying melted—an average of 22 days earlier in the Northern Rockies, according to a 2011 study in the American Meteorological Society Journal. The glaciers are retreating, and spring is coming earlier.
As the climate continues to warm, it could spell disaster for the niche snowshoe hare population and the ecosystem that relies on it. Like so many stories of climate change, this seems like one of impending doom. If humanity doesn’t dramatically change the trajectory of global warming, places like Glacier will never be the same. But this story has a hopeful ending.
“Let’s not jump straight to conclusions,” Mills warns.
That’s the founding principle behind the Mills Lab at the University of Montana where researchers from all disciplines are studying how ecosystems are responding to human-caused environmental change.
Nature to the Rescue
While human intervention is necessary to slow the devastating effects of climate change on places like Glacier, nature herself has already come up with a quick fix, says Mills. Evolution may be able to rescue species like the hares.
The genetics that cause the hares to change colors vary between animals. Some change early, some change late or not at all. Those that change with the most accuracy to their environment survive and reproduce—it’s natural selection. Hares at lower elevations tend to stay brown longer, where those at higher elevations stay white longer.
According to Mills’ research, for natural selection to take place the fastest there must be large, connected populations of the low and high elevation hares in Glacier, and other stressors, from increased urbanization to invasive species, have to be mitigated. As the climate warms and the white hares find themselves mismatched, evolutionary rescue will start to do its job, with more of the brown hares surviving and reproducing.
“Evolution won’t fix everything,” says Mills, “but it’s a way we can help keep these populations from going extinct while humanity works on solving climate change.”
The land managers in the surrounding Crown of the Continent area including Glacier are working to help the ecosystem adapt to a changing climate by reducing stressors that they have control over. These include removing invasive species, reducing human impact and re-assessing infrastructure.
“There’s a lot of uncertainty around climate change,” says Glacier’s superintendent Jeff Mow. “We can’t stop it. Even if we cut carbon emissions to zero tomorrow we’re still going to have to live with the trajectory we’ve put ourselves on. It’s all about adaptation to this new world and building resilience.”
There are signs in the park like at the St. Mary’s Visitor Center showcasing the effects of climate change on its glaciers. They end with a warning, “when they will completely disappear, however, depends on how and when we act.”
Nature is working to adapt to a changing climate in places like Glacier, so there is hope for snowshoe hares, lynx and boreal forests. But as Mills notes, evolution can’t fix everything. The future of our parks is uncertain, and humans hold the keys to the answer. How and when will we act?
Climate change’s effects on our beloved parks can seem overwhelming. What can one person do about it? We asked Katie Boué, founder of the Outdoor Advocacy Project, about ways individuals can get involved in advocating for the wild places we love.
Register to vote or check your voter status at vote.org.
KB: Electing officials that support public lands and reducing the effects of climate change is the best way to protect our parks.
Get involved protecting the places you love
KB: What’s the place you love the most? Get involved in a way that makes sense for you: time, energy, money, skills. If you love Glacier National Park, check out the Glacier Conservancy at glacier.org
Share the places you love
KB: Share the places you love with a message about advocacy. Whether it’s on social media or with your co-workers, talk about the public lands you love and share the issues they face. Everyone who loves public lands has the privilege and responsibility to advocate for them.
Integrate stewardship when you travel
KB: Schedule a day to volunteer with a local conservation organization or even just set
aside a day to hike a trail with a trash bag and pick up trash.
Learn more about Outdoor Advocacy Project and Boué’s work at outdooradvocacy.com.