Alaska is one of the few places in North America where you can watch a marmot emerge from a burrow it has been sealed inside since September. These stocky, whistling rodents spend more time underground than almost any other mammal on the continent, and the moment they finally surface in spring is one of the quieter, more rewarding signs that the Alaskan wilderness is waking up again.
Whether you are planning a wildlife-watching trip or simply curious about what is happening beneath those boulder fields while snow still covers the high country, this guide walks you through everything you need to know about marmot hibernation and emergence in Alaska — species by species, season by season.
Which Marmot Species Live in Alaska
Alaska is home to three marmot species: the hoary marmot (Marmota caligata), the Alaska marmot (Marmota broweri), and the woodchuck (Marmota monax). Each occupies a distinct part of the state and has its own habitat preferences, which is why knowing which species you are looking for matters when planning a wildlife outing.
The hoary marmot is a species of the mountains of northwest North America. Hoary marmots live near the tree line on slopes with grasses and forbs to eat and rocky areas for cover. It is the largest North American ground squirrel and is often nicknamed “the whistler” for its high-pitched warning call used to alert other members of the colony to possible danger. The hoary marmot is found in alpine areas across most of Alaska south of the Yukon River and occurs down to sea level along areas of the coast where suitable habitat exists.
The Alaska marmot (Marmota broweri), also known as the Brooks Range marmot or Brower’s marmot, is a species of rodent in the family Sciuridae. Once considered to be the same species as the hoary marmot, it is now known to be unique. Alaska marmots are found in the scree slopes of the Brooks Range, Alaska. The Alaska marmot inhabits the northern reaches of the state and can be found in the Brooks Range of northern Alaska from near the coast of the Chukchi Sea to at least the Alaska-Yukon border. The Yukon River forms the southern limit of the Alaska marmot’s range and the boundary between the distribution of Alaska and hoary marmots.
The woodchuck digs its den in loess — wind-deposited soils — along river valleys. Woodchuck dens may be up to 30 feet long, are dug in the loamy soils of river valleys in Interior Alaska, and end with a chamber containing a large grass nest. The woodchuck is the most familiar marmot species across much of North America, sometimes called a groundhog, and it rounds out Alaska’s trio of burrowing, hibernating marmots.
Key Insight: The Yukon River serves as a natural dividing line between Alaska’s two mountain marmot species. Hoary marmots live south of the river; Alaska marmots live north of it. Woodchucks occupy a different niche entirely, preferring lowland river valleys rather than rocky alpine terrain.
When Do Marmots Hibernate in Alaska
True hibernators, marmots enter a state of torpor in winter during which body temperature and all bodily functions are reduced. The animals attain their maximum weight in late summer, when they accumulate thick layers of fat that will sustain them through winter hibernation. This is the critical preparation window — without enough fat stored, a marmot will not survive the long Alaskan winter.
The timing of hibernation differs somewhat by species. Hoary marmots emerge in mid-May, become lethargic by late August, and re-enter the burrows as early as early September. The onset of hibernation is gradual, with a steady decline in social activity, foraging, and time spent above ground.
Alaska marmots enter their dens even earlier. Alaska marmots hibernate for the majority of the year. Hibernation begins around the first major snowstorms in late August and early September and continues until the snow begins to melt and food becomes available in early June. Winter dens have a single entrance on a windswept ridge that becomes snow-free in early spring; Alaska marmots plug the entrance with dirt, vegetation, and feces once all members of the colony are inside the den, usually by September, and hibernate through the winter.
The Alaska marmot is one of the longer-hibernating marmots, being documented to do so up to eight months annually. Because hibernation begins in September, most marmots in Alaska spend two-thirds of each year locked in their winter dens.
Pro Tip: Alaska marmots hibernate communally as a family unit, which researchers believe helps them conserve body heat in the Arctic cold. Hoary marmots and woodchucks, by contrast, hibernate alone in their summer burrows — a meaningful behavioral difference between the species.
During hibernation, marmot physiology changes dramatically. During hibernation, many of their body functions decrease, including body temperature, which averages between 4.5°C (40.1°F) and 7.5°C (45.5°F), as well as heart rates and respiratory rates. Hibernation in Alaska marmots is discontinuous. Individuals awaken every three to four weeks to urinate and defecate, after which hibernation is resumed.
When Do Marmots Come Out of Hibernation in Alaska
Spring emergence is one of the most eagerly anticipated events in Alaska’s alpine landscape, but the timing varies by species and elevation. As a general rule, the hoary marmot surfaces first, followed by the Alaska marmot a few weeks later — a reflection of their different geographic ranges and den designs.
Hoary marmots emerge from their winter hibernation in April or early May to find food and mates. When they retire for the year, they often plug the entrance to their burrow with rocks and mud and are seldom observed above ground after the first of September, not to be seen again until late April. This gives hoary marmots an active season that runs roughly from late April through late August — a window of just four to five months in which they must feed, breed, raise young, and rebuild fat reserves.
The Alaska marmot’s emergence is tied directly to the thaw of its den plug. Winter dens are built on exposed ridges that thaw earlier than other areas, and the entire colony stays within the den from September until the plug melts in early May. The Alaska marmots will generally emerge from the den during the first two weeks of May.
Important Note: Elevation plays a significant role in emergence timing. Marmots at lower elevations or on south-facing slopes may appear earlier in the season, while those higher in the mountains or on north-facing ridges may remain in their dens well into May. If you are watching a specific site, expect natural variation of a week or two in either direction.
One of the most remarkable adaptations of the Alaska marmot is that mating does not wait until after emergence. As an adaptation to the Arctic environment and permanently frozen ground, Alaska marmots breed prior to emerging from the winter den. Males mate with one or more females living in their territory, once per year, usually in early spring while still in the den. This strategy ensures that the very short active season above ground is used as efficiently as possible. You can also learn about how other animals time their spring activity in Alaska by reading about when snakes come out in Alaska.
What Marmots Do Immediately After Hibernation in Alaska
The hours and days following emergence are a busy, purposeful time for Alaska’s marmots. After months sealed underground, they face a rapid set of biological priorities — and their behavior reflects that urgency.
A marmot leaves its winter sleep very thin but quickly gains weight, with fat stored for hibernation making up 20% of its body weight at the end of summer. In the immediate aftermath of emergence, foraging is the top priority. The hoary marmot is a diurnal herbivore and feeds on grasses, flowering plants, berries, roots, mosses, and lichen. Hoary marmots show selective foraging behavior, feeding first on favorite plants rather than ones that may be more abundant.
For hoary marmots, mating follows quickly after emergence. Hoary marmots breed in the early spring, shortly after emergence from hibernation. In Alaska, all marmots mate in April or May. Females come into estrus within one to two weeks of surfacing, making the post-hibernation period a socially active and sometimes competitive time within each colony.
Another early post-emergence behavior is den maintenance. In the spring, the winter nest is frequently thrown out of the burrow and replaced by a new one of fresh grasses. This housekeeping task is followed by territory marking. The hoary marmot marks its territory by rubbing its face and glands on rocks and along trails.
In the summer, activity above ground peaks in the morning and late afternoon. Marmots may facilitate their energy intake by adjusting their behavior to capture radiant energy during low temperatures. They do this by sunning themselves on rocks and sprawling on the ground near their burrows.
Common Mistake: Many visitors assume a marmot they spot right after emergence is fully recovered and energetic. In reality, freshly emerged marmots are at their lowest body weight of the year and may appear sluggish. Their activity ramps up noticeably over the following weeks as food becomes available and temperatures rise.
Young marmots born the previous year also have an important milestone shortly after emergence. Around six weeks of age, the young have dense, soft fur and are independent enough to explore outside the den. Young marmots first appear in late July, making mid-to-late summer the best time to watch for juveniles alongside adults at active burrow sites. You might also be interested in learning about when bears come out of hibernation in Idaho or when bears emerge in Colorado for a broader look at how large hibernators time their spring activity.
Where to Spot Marmots in Alaska
Alaska offers several excellent locations for marmot watching, though the species you are most likely to encounter depends heavily on which part of the state you visit. The key in every location is the same: look for rocky terrain, boulder fields, and talus slopes where marmots can den safely and scan for predators.
| Location | Species Likely Present | Best Habitat Feature |
|---|---|---|
| Denali National Park | Hoary marmot | Alpine talus slopes, rocky sections along park road |
| Brooks Range | Alaska marmot | Scree slopes, boulder fields near tundra |
| Chugach State Park (Anchorage) | Hoary marmot | Steep mountainsides, rocky outcrops |
| Denali State Park | Hoary marmot | Alpine foothills, rocky alpine zones |
| Interior Alaska river valleys | Woodchuck | Loamy river valley soils, open ground near water |
In Denali National Park, the animals you can hope to see include moose, bear, caribou, wolves, Dall sheep, and other small land mammals like marmots, as well as a variety of birds. Marmots and pika are only found in rocky sections of mountains. To see different types of smaller mammals, Savage River at Mile 15 is a great area to explore.
At Chugach State Park, if you tread quietly you may catch a glimpse of small mammals like the arctic ground squirrel, the adorable round-eared pika, or the hoary marmot. A 20-minute drive out of downtown Anchorage, Chugach State Park offers over 495,000 acres of rugged wilderness, making it one of the largest state parks in the country and the third-largest in Alaska. Its accessibility makes it one of the most convenient places in the state to observe hoary marmots without a remote expedition.
Denali State Park, located in the foothills of the Alaska Range, is a haven for moose, caribou, fox, Dall sheep, wolves, mountain goats, marmots, lynx, and many species of birds.
For Alaska marmots specifically, the Brooks Range is the place to go. Alaska marmots are social creatures and live in colonies, all sharing an immense burrow system. Dens may be located in extensive boulder fields, rock outcroppings, or active talus slopes with large rocks adjacent to productive tundra. Access to this region typically requires a fly-in or a journey along the Dalton Highway, but the reward is a glimpse of one of North America’s most rarely observed marmot species. You can compare Alaska’s spring wildlife timing with other states by reading about when bears come out of hibernation in Maine or when bears emerge in California.
How to Tell If a Marmot Is Active in Alaska
Even when marmots are technically above ground during their active season, they are not always easy to spot. Knowing their behavioral patterns and sensory cues will dramatically improve your chances of a successful sighting — and help you distinguish a genuinely active animal from one that is simply sunning near its den entrance.
Marmots are most active in early morning and late afternoon, although they may leave their burrows during other daylight hours. Marmots need wind to control mosquito levels and rarely venture out on calm days. This is a particularly important detail in Alaska, where mosquitoes can be intense during summer months. The behavior of Alaska marmots is strongly influenced by mosquitoes. During the summer months in Alaska, mosquitoes can be extremely abundant. This causes individuals to remain inside their den on warm, sunny days when the mosquitoes are out in vast numbers. Alaska marmots are most active on cool, cloudy, windy days when the mosquitoes are not active.
The most reliable indicator that marmots are active is their alarm call. The alarm call of both the hoary marmot and the woodchuck is a loud whistle. When the Alaska marmot is alarmed, it produces a two-toned, high-pitched warning call. If you hear a sharp whistle echoing across a boulder field, there is almost certainly a marmot nearby — and it has already spotted you.
All adult Alaska marmots spend time on sentry duty, standing on top of observation points on the lookout for predators. When a predator is spotted, the marmot on sentry duty will emit an alarm call, which alerts the other individuals outside of the dens of the potential danger, causing them to retreat back inside their respective dens.
Pro Tip: If you want to observe marmots without triggering an alarm, approach slowly and use natural cover like large rocks. Sit quietly downwind and give the colony time to settle. Marmots that have not been disturbed will resume foraging and social behavior within minutes of a perceived threat passing.
Visual signs of activity around a den site are also helpful. Well-beaten trails extend from the burrow entrance to feeding locations. Fresh digging, scattered plant material near the entrance, and worn pathways on rocky surfaces all suggest that a burrow is currently occupied. Hoary marmots are predominantly gray with a darker lower back and face and a dark, reddish tail — a color pattern that blends well with lichen-covered rocks, so scanning slowly and patiently is more effective than a quick sweep of the terrain.
Finally, watch the surrounding landscape for signs of recent snowmelt and new plant growth. Marmots track food availability closely, and areas where early-season grasses and forbs are emerging are exactly where you are most likely to find them foraging in the hours after sunrise. For more on how Alaska’s wildlife responds to seasonal change, see our guide on when snakes come out in Alaska, or explore how hibernation timing compares in states like Massachusetts, Connecticut, and Maryland.