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The environment desk at Aspen Public Radio covers issues in the Roaring Fork Valley and throughout the state of Colorado including water use and quality, impact of recreation, population growth and oil and gas development. APR’s Environment Reporter is Elizabeth Stewart-Severy.

The Marmots of RMBL

Ellis Robinson, Aspen Public Radio

A colony of small mammals lives high above Crested Butte, just on the other side of West Maroon Pass from Aspen.  And, for more than fifty years, the Rocky Mountain Biological Laboratory there has been watching the daily lives of these yellow-bellied marmots.  It’s one of the longest running animal studies in the world.  Our science reporter Ellis Robinson spent several days hanging out with the marmots and the “marmot-teers” who study them.  In the first of two reports, Ellis explores what data the researchers are collecting.

The mountains and meadows around the town of Gothic are outdoor laboratories for UCLA Professor Dan Blumstein.  But to get an interview with the guy, you better be able to keep up. On a mountain bike.

“What scientists do you think are in the best shape?” I asked him during our ride-interview. “I don’t know.” He answered, distractedly “Ok, we’re gonna park right here.”

Blumstein directs a field ecology study of yellow-bellied marmots at the Rocky Mountain Biological Laboratory, RMBL (pronounced “Rumble”) for short. 

Now on its 53rd year, the marmot research at RMBL is one of the longest-running animal field studies in the world. And its long-term dataset has led to a number of important insights both within the field of ecology, and beyond.

“Marmots understand the academic calendar. And because they understand the academic calendar, you can get most of their life when school’s aren’t in session.”

What this means for Blumstein’s team of researchers, is skiing up to the field site in the spring, where they live in cabins until the marmots hibernate, in the fall.

“Climate change of course is changing that because now they’re getting up a day earlier every year. So that’s actually, in the long-run, a good chunk of time.”

As they began emerging earlier each year, RMBL’s marmot population sky-rocketed in the early 2000‘s. Because the marmots were coming out of their burrows earlier, they had the chance to fatten up longer and reproduce more. You might call them one of the early winners of climate change. But that’s just one of the questions being answered by the “marmot-teers.”

“I can’t keep track of them all. I’ll show you the spreadsheet, it’s out of control,” says Blumstein.

The list is long.  And on it is the question how individuality emerges in marmots?  Believe it or not, the personalities of individual marmots can have big impacts on the larger population numbers. Blumstein relates the story of one grumpy female marmot who controlled an entire meadow and chased her daughters out, not allowing them to breed. After she died, 5, more peaceful female marmots moved into her territory and began reproducing.

“The real interesting questions are what are the benefits of having different types of animals around in the first place. So when there are lots of predators around, maybe it’s not good to be bold, maybe it is good to be bold.  And so we’re testing some of those, as we speak.”

Marmot personality is something the team spends a whole lot of time looking at. “We are out in the field like... a lot of time (laughter).” That’s graduate student Adrianna Maldonado Chaparro.  We spent an afternoon sharing a pair of binoculars. “We are out in the field since seven in the morning til ten, ten-thirty. And then in the afternoon, we come around four and we stay out until  six, six-thirty.”

After awhile, two females emerged and started playing. “So that’s what we do all day long. You know... line-dot-line greets musical note,” says Chapparro. Line-dot-line? Musical note? Those are the names of the marmots, identified from a distance by marks that the researchers put on their backs.

Across the meadow at another burrow, PhD student Tiffany Armenta weighs marmots she trapped earlier.  It is a routine measurement, but one that allows the team to understand why some marmots live, others die, and helps explain why the marmots began to thrive when climate started changing.

For more than 50 years up here, in lonely Gothic, Colorado, a small team has spent countless hours observing, tagging, weighing, and taking blood from generations of yellow-bellied marmots.  The resulted data they have collected has featured in discoveries about such diverse topics as mammalian personality traits, climate change, and the evolution of fear.

And these insights would not have been possible without the solitary work of graduate students, spending their days sitting in fields looking at marmots with funny names. Armenta: “Like who are we missing here... Dracula?”

For Aspen Public Radio, I’m Ellis Robinson

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