By Michael Dallin
The yellow-bellied marmot (Marmota flaviventris) is a favorite animal to many alpine visitors. Marmots, which are also called rockchucks or whistle pigs (because of their "alarms" when threatened), are related to ground squirrels. Thier fur is generally light brown, with a yellow-ish belly and white spots on and around thier noses. They have large bushy tails, and prominant teeth used for gnawing. They are usually found above treeline, especially in rocky outcrops.
Marmots spend most of the year in hibernation -- from September through April, roughly. During the summer months they mostly eat and relax, and can often be seen resting on rocks of the tundra. Marmots spend most of the time relaxing for good reason -- to conserve energy for the long winter hibernation. Marmots breed briefly after they emerge from thier hibernation, and their young are born a month later.
The marmot diet consists mostly of alpine grasses. They build dens in rocky outcrops, or scree slopes.
If you come close enough to a marmot, you are likely to hear their loud, piercing alarm whistle. Their natural predators include foxes, badgers, and coyotes. Marmots also use this whistle to keep tabs on other marmots.
Rocky Mountain National Park