Changing Rhythms

Grizzly in snowy lodgepole forest
This year's below-average snowpack levels in the Northern Rockies are one of many climate-related impacts creating a murky future for grizzly bears in the Lower 48.

What the Climate Crisis Means for the Future of Grizzly Conservation

By Kayla Heinze, Communications and Outreach Coordinator
from Vital News, Spring 2024 edition

Like a beautiful song, the lives of bears rise and fall with a cyclical rhythm. In springtime, grizzlies become active once again after winter denning. Sows with newborns or yearling cubs explore the valley bottoms looking for greenery and other spring foods. Adults without cubs roam the landscape, often heading upslope to find each other and mate. Later, as summer berries ripen, bears in all life stages begin to focus more of their energy on foraging. Come fall, the intense hunger period called hyperphagia fully sets in and bears eat incessantly to build up their fat stores in preparation for winter.

For tens of thousands of years, grizzlies have attuned to the seasonal availability of foods and evolved this cyclic strategy to avoid harsh winters. Their physiology and behavior are significantly tied to the patterns of their environment, their activity matching the fluctuations of the world around them.

Now, the climate crisis is radically altering these rhythms. While weather and natural systems are inherently variable, grizzlies in the Northern Rockies have always been able to keep tempo with the dynamic ecosystem and play their part in the larger orchestra of life. But it’s becoming increasingly difficult to keep that melody going. Bears and every other wild creature, including us, are struggling without a stable beat. The music isn’t just changing this time—for many species, it’s at risk of stopping altogether.

Like us, grizzlies are amazingly adaptive but not endlessly so. With lifestyles so intimately connected to the cycles of the landscape, rapid change makes it hard for this slow-reproducing species to keep up. Climate change is undeniably threatening, but we can give grizzlies, and ourselves, a fighting chance in an uncertain future by protecting the landscapes that we all depend on.

Climate Knowns and Unknowns

Buffaloberry in Yellowstone
Buffaloberries provide an important food source to bears, but the overlap between the plant’s fruiting season and bears’ peak foraging period is shrinking. (Photo courtesy of Yellowstone National Park)

The Northern Rockies experienced unusually warm temperatures and low levels of precipitation this winter. Just one manifestation of increasing average temperatures and extreme weather patterns ahead, this winter will impact the physical and social landscape for months. Based on these dry conditions, experts predict limited huckleberry production this summer. Poor berry crops can drive hungry bears toward other food sources, including those that bring them in closer proximity with people.

But the concern isn’t just potentially fewer berries—changing weather patterns are also making berries ripen earlier, before bears enter their peak foraging window. This misalignment is one of the ways the climate crisis is shifting bears out of tune with their surroundings. From declines in Yellowstone’s native trout population to the decimation of whitebark pine stands, many of the plants and animals that grizzlies rely on are hurting because of the rapid and widespread changes on the landscape. Those that are hanging on may have to shift their ranges to find endurable temperatures, which could alter where grizzlies go too.

Whitebark pine has been a major food source for grizzlies across the Northern Rockies, with seeds rich in fat and essential amino acids. Found at high elevations, this nutritious food keeps bears in habitat infrequently visited by people. But whitebark stands are suffering the combined effects of fire suppression, drought and heat stress, as well as beetle outbreaks and fungal infections that were once kept in check by colder winters. As their availability continues to decline, research in Yellowstone indicates bears will switch to a meat-heavier diet, putting them at greater risk for conflict as they approach roadkill or livestock.

We also know that warmer winters can confuse grizzlies about when to enter and exit their dens. Higher temperatures and reduced snowpacks can cause bears to leave their dens earlier in the spring, creating a wider window for potential conflicts with people. The heat gets to them during the summer, too. With dense fur and no access to air conditioning, bears must limit their activity when it gets too hot, which is now the case both for more days of the year and for more hours of the day.

A male grizzly bear wanders the early spring landscape of Yellowstone  in search for food to replenish fat stores lost during winter denning. (Photo courtesy of Yellowstone National Park)

But these challenges aren’t the whole story for opportunistic, adaptable grizzlies. Some species that bears rely on for food may expand and grow more abundant in response to warming. Thanks to less-stable global weather patterns, climate change also contributes to freak cold snaps, which can kill deer and elk, increasing carrion scavenging for bears in spring. And there are likely many climate-related changes that scientists have yet to predict. With global warming, habitat loss, development and other threats all intimately interconnected, the impacts for bears could compound in still-unknown ways.

While we don’t know exactly how the climate crisis will play out, especially on local scales, we know enough to be concerned. Due to its broad effects, many conservationists call climate change the biggest existential challenge for grizzlies. In 2009, a federal judge cited the need to more fully consider climate impacts in her decision to maintain the species’ listing status as threatened under the Endangered Species Act.

In search of new food sources, on a rapidly developing landscape with more people than ever, bears are at an increased risk of conflicts that harm both them and us. More conflicts, in turn, can decrease social tolerance for the species and weaken support for their protection. While this is a worrying outlook, we have many resources to prevent it. The biggest thing we still don’t know about the future, however, is what we, as a human species, are going to do.

Wildlife Conservation for Resilient Futures

As author Terry Tempest Williams says, “When I see a grizzly, I see the potential of who we really are.” We have both the potential to continue wreaking havoc on our shared landscapes or the potential to protect these precious places for the benefit of all life. As a supporter of Vital Ground, you enable us to collectively choose the better path. Your generosity and commitment allow us to counteract the threats to grizzlies and give the species a chance in a changing world.

Bismark Meadows
Vital Ground’s Bismark Meadows project in North Idaho protects crucial low-elevation wetlands where grizzly sows with newborn cubs can forage safely in spring. (Photo by Linda Lantzy)

Bears are highly intelligent, opportunistic creatures capable of remarkable adaptation. But the isolation and low genetic diversity of the Lower 48’s grizzly populations limits their potential for adjustment, as does the landscape fragmentation that makes it difficult for bears to move freely to better habitat. Your support of Vital Ground’s mission to protect and connect the remaining open spaces improves the opportunities for bears to roam safely. Conserving lush wetlands and intact forests helps even further, sequestering carbon and giving the native plants and animals bears rely on a stronghold for survival.

You also help Vital Ground proactively address and prevent conflicts. Through our robust conservation partner program, we are helping local communities cope with the increased potential for conflicts due to climate impacts and expanding bear populations. We prioritize coexistence and habitat protection in recognition that our fates are linked with grizzlies and other wildlife. When bears can thrive in their natural environment, they’re less likely to cause damage or injury to us and our ecosystems become healthier and more resilient from their presence.

As creatures on a planet in crisis, we’re all part of the same choir. Our landscapes are changing with unreliable tempos, and many have suffered already for it. But the song’s not over yet. We thank you for your ongoing investment in our conservation work to ensure the beautiful music and natural rhythms of the Northern Rockies can continue unfolding for all to enjoy. ­

Support habitat protection with a sustaining membership today…

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