Fat Marmot Week Launches to Highlight Alpine Rodents’ Climate Struggle

Researchers at the Rocky Mountain Biological Laboratory launched Fat Marmot Week on Monday, August 24, inviting the public to celebrate yellow-bellied marmots as they fatten up for winter hibernation. The six-day tournament-style event runs through August 29 and mirrors the popular Fat Bear Week contest, but with a serious environmental message about climate change impacts on high-alpine ecosystems.

The timing carries particular urgency following a devastating winter for marmot populations in the Colorado mountains. Scientists report that two-thirds of one population died during hibernation last winter due to insufficient snow cover, underscoring how unpredictable weather patterns and wild fluctuations in snowfall threaten these charismatic rodents’ survival.

“It’s fun to root for the chunkiest marmot, but behind the fun and games is a deathly serious competition against nature to pile on fat to survive the long, cold winter,” said Dan Blumstein, professor of ecology and evolutionary biology at UCLA and co-director of the RMBL Marmot Project. “And these days, with less predictable weather and wild fluctuations in snowfall, survival is not guaranteed.”

Raising Funds as Federal Support Dwindles

UCLA graduate students Katie Adler and Emily Renkey run Fat Marmot Week as both entertainment and a critical fundraising initiative. The event aims to raise money for scientists to continue long-running research at the Rocky Mountain Biological Laboratory in Gothic, Colorado, as federal funding cuts threaten ongoing studies of these rodents.

The contest invites participants to vote for their favorite marmots as the animals undergo their remarkable summer transformation. Yellow-bellied marmots feed almost constantly on grasses and wildflowers throughout the warm months, eventually doubling their body size in preparation for approximately five months of hibernation.

Understanding Marmot Behavior and Personalities

Marmots are cat-sized, furry ground squirrels that live in burrows across North America, Europe, and Asia, with approximately 15 species worldwide including groundhogs. In the Rocky Mountains, yellow-bellied marmots thrive as plentiful residents that hikers often spot perched on boulders or scurrying through wildflowers.

Experts describe these creatures as exhibiting distinct personalities and displaying what researchers call “flexibly social” behavior. Some marmots prefer to intermingle in colonies of up to 30 animals, while others choose solitude over group living.

“We kind of understand these marmots just by looking at them sometimes, because we can kind of tell who’s who just by how they behave and how they interact with one another,” said Adler, a doctoral student at the University of California, Los Angeles.

The researchers encounter varied temperaments during fieldwork. Some marmots demonstrate wariness toward researchers’ efforts to trap them using wire boxes baited with an enticing mixture of oats and peanut butter, according to Renkey, a UCLA master’s student. “Others, you could trap three or four times in the same morning,” Renkey said.

True Hibernation Versus Bear Torpor

Fat Marmot Week deliberately contrasts with Katmai National Park’s famous Fat Bear Week featuring Alaskan brown bears. While bears plump up for winter, they do not truly hibernate regardless of how much weight they gain. Bears enter what scientists call torpor, a sleeplike state in which their body temperature remains fairly high and they can wake up or be woken periodically.

Marmots, by contrast, are true hibernators that slip into a far deeper form of hibernation. Their body temperature plummets from approximately human levels to as low as 41°F (5°C), barely warmer than their winter burrows. The animals plug their burrows when food sources dry up and temperatures drop, remaining underground until snow begins melting in spring.

“You pick up a hibernated marmot and it’s this fuzzy ball and it feels like a cold rock with fur. It’s completely surreal,” Blumstein said. “They breathe once a minute or two.”

Climate Change Threatens High-Alpine Ecosystems

The dramatic winter mortality highlights how climate variability increasingly challenges marmot survival. Yellow-bellied marmots depend on adequate snow cover during hibernation, and insufficient snowpack creates life-threatening conditions. The animals’ extreme physiological transformation during hibernation-turning body temperature and heart rate down to practically nothing-requires sufficient fat reserves accumulated during summer feeding.

Those marmots that survived last winter’s harsh conditions are currently doing well, researchers report, fattening up in time for fall and the approaching hibernation season. Their recovery underscores the species’ resilience when environmental conditions cooperate, but also emphasizes how precarious their annual survival cycle has become.

“Importantly, marmots give us a window on the health of high-alpine ecosystems,” Blumstein explained. Julien Martin, professor at the University of Ottawa, serves as co-director of the RMBL Marmot Project alongside Blumstein.

Celebrating Wildlife Science Through Public Engagement

Fat Marmot Week represents the latest effort by Blumstein’s lab to raise public awareness and research funds through creative outreach. The professor previously generated attention by creating an OnlyFans account featuring the marmots he studies, making the roly-poly rodents what some observers call the “it” squirrels of summer.

The contest format allows participants to learn about these cute alpine residents while supporting ongoing scientific research. The tournament-style voting creates friendly competition around identifying which marmots achieve the most impressive weight gain before winter arrives.

Marmots join the ranks of other celebrated ground squirrels, including groundhogs, which Americans and Canadians honor every February 2 during Groundhog Day. Fat Marmot Week extends this tradition of recognizing these charismatic creatures while adding contemporary conservation messaging about climate impacts on vulnerable mountain ecosystems.

The inaugural event invites nature enthusiasts worldwide to participate in voting while learning how researchers track individual animals, study their social dynamics, and monitor population health across seasons. As unpredictable weather becomes the new normal in high-altitude environments, initiatives like Fat Marmot Week serve dual purposes-entertaining the public while funding crucial long-term ecological research that documents how alpine species adapt to rapidly changing conditions.