The fattest marmot has been crowned. 

After three rounds of bracket-style voting and social media buzz, Dawn emerged victorious from Fat Marmot Week, which was hosted for the first time by Colorado’s Rocky Mountain Biological Laboratory. 

Weighing in at 13 pounds, Dawn prevailed over G in a field of eight photographed in their chunky, pre-hibernation glory and briefly profiled on Fat Marmot Week’s website. Dawn was noted as “a very special boy” who “watches carefully over his pups while they play.” He has also been known “to travel across his territory and check on his ladies” ー while having managed to add 4 pounds ahead of winter slumber. 

Those were but a few observations among the countless that have been recorded by scientists and students over six decades at the Rocky Mountain Biological Laboratory in Gothic, near Crested Butte. 

The idea for Fat Marmot Week came out of the lab’s Marmot Project, which in 1962 started studying the ways of the charismatic alpine dweller in the surrounding mountains. Fat Marmot Week would be a take on the longer-running, beloved Fat Bear Week, in which voters have rallied around the burliest of bruins pictured at Alaska’s Katmai National Park and Preserve. 

Fat Marmot Week “became much bigger than we could have ever imagined,” said Katie Adler, a Marmot Project team lead who answered nationwide media requests while tallying some 23,000-plus votes.

Mission accomplished ー and not just from the standpoint of promoting Rocky Mountain Biological Laboratory, Adler explained. “Science communication,” connecting with a broader audience, has been an interest of hers while pursuing a Ph.D at the University of California, Los Angeles.

Fat Marmot Week was about “getting more people educated on marmots,” Adler said, “and getting people excited about wildlife and long-term studies in general.” 

A study like the Marmot Project is rare. Into its 64th year, it calls itself “the world’s second longest-running study of individually marked mammals behind only Jane Goodall’s famous chimpanzee research.” 

Those marks of non-toxic dye atop the fur inspired the names of Fat Marmot Week’s thick contestants. There was Open Kite, the “girl boss” profiled on the website. There was Citroen, “Open Kite’s new man,” who “has taken his role as stepdad to last year’s pups very seriously.” 

There was Dan’s Hat, “the cool aunt who’s part of Stonehenge’s matriline. (Matrilines form when adult females let their daughters stay in the social group instead of dispersing.)” As for Stonehenge: “She once yelled at some bikers 3,000 times in a single hour.”

Also: “She reproduced this year only to lose her litter to a hungry badger.” 

Yes, from the very beginning, life is hard for a marmot. Marmot Project researchers have tracked about 50% of pups dying before their first birthday. 

The task is steep in the high country: feasting on enough grass, flowers and forbs to store enough fat to survive potentially eight months of hibernation, all while evading predators from land and sky (foxes, coyotes, raptors, etc.). And then there’s the threat of increasingly unpredictable weather patterns, as Marmot Project researchers have been following. 

The historically dry winter of 2025-26 was especially brutal for marmots that depend on the snow for “an insulating blanket,” Adler explained. To make up for the lack, they spent more energy and burned fat, she said. “We lost like 100 out of 160 animals this year because of that.” 

But marmots are “really resilient,” Adler went on and drought comes with “a lot of trade-offs.” For example: earlier snowmelt means an earlier wake-up, which means more time for marmots to eat up before burrowing away in late September. More time foraging also means more time for predators to find them. 

Nonetheless, Adler found some marmots weighing in early August what they more commonly weigh in early September. This was good for the inaugural Fat Marmot Week. 

Even better, from Adler’s view: “People are interested and they’re sticking around.”

Sticking around to learn more. 

On the Marmot Project website, they might sift through more than 250 papers going back to the 1960s, with titles alluding to “male behavior and territoriality” and “alarm calling” and “juvenile play” and much more. 

Marmots “are remarkably flexible in their social lives,” reads a synopsis. “While many animals, including primates and some marmot species, depend on living in groups to survive or raise young, yellow-bellied marmots can thrive alone or in groups of more than 20 animals.”

Similar to elk, males form harems of females, which are immediately pursued out of hibernation. Researchers once observed a bachelor waiting above a burrow with a flower. 

“We’ll see a male sitting alone in the snow for a couple of days, and he’ll just be digging and digging and digging,” Adler said. “And a couple of days later, a female will pop out of the burrow.” 

Later, “when they’re preparing to give birth, you’ll see mothers bring a ton of plants to the burrow to basically make a bed,” Adler said. 

And later, a female might be seen calling to her fellow colony members to warn of a nearby predator. If need be, a mother might come between that predator and her pups. 

In short, Adler said: “We’re not so different from marmots.”

As participants of Fat Marmot Week might have learned while voting for their favorites. Of course, in the case of losses, disappointment was felt.

“I had a couple I was rooting for,” Adler said, “but I’m rooting for all of them.”