Putting Yosemite to Bed for Winter

Echo Adventure Cooperative Members

1 day ago

6 min read

An October field note from Echo Adventure Cooperative

On an October walk, Yosemite can seem to be winding down. The meadows turn gold, the first snow may brush the high peaks, and the days get shorter. But wait, watch a little longer... A pika hurries through a talus field with a mouthful of plants. A black bear searches beneath an oak. A gray-and-black bird calls from a whitebark pine. All three are preparing for winter, and each has a different strategy.

In a park that rises from foothill oak woodland to alpine rock, winter does not arrive everywhere on the same day. Nor does every animal respond by going to sleep. Some store energy in their bodies, some store food in one place, and some spread thousands of small stores across the landscape.

The bear: Thicc with two c's

In fall, Yosemite’s black bears enter hyperphagia: an intense period of feeding that builds the fat reserves needed for denning. Black oak acorns can be especially valuable. In a year when acorns are abundant, a bear may spend a remarkable amount of time feeding beneath the oaks in Yosemite Valley. The park’s bear team says bears can consume as much as 20,000 calories a day during this period; that is an upper figure, not every bear’s daily intake.

Denning follows food availability as much as the calendar. Bears may begin looking for dens in October, yet some continue feeding into winter when food is available. Their winter state slows heart rate, breathing, and metabolism, but it is not an unbroken, unconscious sleep. A bear can wake and leave its den. That is one reason food storage rules matter in every season: a cooler, car, or campsite must never become part of a bear’s fall food supply.

The pika: Making hay

High above the Valley, the American pika takes another route. This small relative of rabbits and hares stays active through winter. In the warmer months, it gathers grasses, leaves, and flowers and builds a haypile, a stored supply of vegetation among the rocks. This is a form of larder hoarding: concentrating food in a defended place for later use.

Talus is more than a pile of loose rock. Its crevices provide shelter and a more buffered space beneath the snow. A pika can move within that rocky shelter and draw on its stored plants while the meadow above is buried. If you hear its short, sharp call in the high country, give it room to keep working; its growing season is brief.

The marmot: So chonky!

Pikas often share a mountainside with yellow-bellied marmots, but the neighbors have different plans. Marmots eat heavily during the entire short growing season and store that energy as body fat. Then they retreat to burrows and hibernate, greatly reducing the energy they need until spring. This is why marmots are prone to A marmot sunning itself near the Tioga Road in fall and a pika gathering plants nearby are facing the same winter with two different solutions: stored fat and stored food.

Marmots can look like approachable little mountain neighbors, especially when they linger near popular viewpoints such as Olmsted Point. But an animal that tolerates people is not asking for a snack. Repeated feeding can teach marmots to associate visitors with food, changing their natural foraging behavior and encouraging begging or even biting. Human food can also harm wildlife’s nutrition and health. Their short summer feeding season is preparation for months underground; let them build those reserves on their natural diet. Never feed a marmot, even a seemingly healthy treat, and pack out every crumb and food scrap.

In Yosemite, keep at least 25 feet from marmots and other small wildlife—even when they approach you. The best way to help these winter-ready chonks is to let them stay wild.

The nutcracker: ADHD of hoarding

Listen for the rough call of a Clark’s nutcracker around Yosemite’s high, open forests. This member of the crow family harvests pine seeds and buries them in many small caches. That is scatter hoarding. Instead of defending one pantry, the bird distributes its food across a wide area and uses its spatial memory to find many of those stores months later, even after snow falls.

Clark's Nutcracker | NPS Website | Jim Peaco

At Yosemite’s treeline, this behavior is tied to the future of whitebark pine. Its large, wingless seeds do not travel far on the wind, and its cones do not simply open and release them. Nutcrackers pull out the seeds and carry them away. Some buried seeds are never recovered; in suitable sites, they can germinate. The bird’s winter pantry thus helps plant the next generation of high-country trees. Whitebark pine, in turn, provides energy-rich food for wildlife in a demanding landscape. The relationship is called mutualism: both species benefit, though the pine depends particularly strongly on the bird for seed dispersal.

The high country has another kind of larder hoarder, too. Douglas’s squirrels collect conifer cones and seeds in concentrated stores, often in moist places that help keep cones from releasing their seeds too soon. A mound of stripped cone scales beneath a favorite feeding perch may be a clue to one of their territories. In the lower oak woodlands, acorn woodpeckers make a more visible pantry, fitting acorns into holes they drill in a shared granary tree. Their family groups defend and use that supply through winter. From pine seeds to acorns, a forest can be full of stored food even when it looks still.

Beneath the ice, life continues

What happens to the trout when the lakes freeze? They remain in the water. Fish are ectotherms, meaning their body temperatures track the water around them, so colder water generally slows their metabolism and changes how much energy they need. Trout may use deeper water or sheltered stream habitat and can still feed through winter. A frozen surface does not mean a lake is frozen solid.

But there is a distinctly Yosemite complication: many high-elevation lakes were naturally fishless. Herders, tourists and governments have introduced trout into many of them over the last two centuries, and those fish can prey on the Sierra Nevada yellow-legged frog. The frog’s tadpoles may spend multiple winters alive beneath lake ice before becoming adults. Both fish and frogs need water deep enough to persist through winter, which is why introduced trout can make crucial frog habitat unusable. Yosemite has removed nonnative fish from selected lakes to help restore those native aquatic communities. Winter beneath the ice is a living ecosystem, with its own conservation story.

The season changes the map

Mule deer may move downslope toward thinner snow, while some birds leave high-country waters before they ice over. Other species remain and make use of shelter, stored food, or the openings that winter leaves behind. Yosemite is rearranging its activity, not switching it off.

Our routes change, too. October snow in the high country may melt quickly or cause a temporary closure. Tioga Road and Glacier Point Road usually close for the season sometime in November, but weather determines the timing. Once Tioga Road closes, there is no drive-through access to Tuolumne Meadows or across the park to the east side.

Yosemite Valley and the west-side entrances remain accessible by road year-round, subject to storms and chain controls. Overnight parking along Tioga and Glacier Point roads is prohibited beginning October 15, even while those roads are open for daytime travel. Check Yosemite’s current road conditions before heading out.

Tioga Road at Tenaya Lake in Late October

October is a wonderful month to slow your own pace and notice the preparations: a bear under the oaks, a cone-scale midden, a nutcracker crossing the sky, or a pika calling from the rocks. The more closely we look, the clearer it becomes: Yosemite is putting itself to bed in a hundred different ways and much of its work continues all winter.

Echo Adventure Cooperative is a worker-owned guide service rooted in the Yosemite region. We share local knowledge to help visitors explore with curiosity, prepare for changing conditions, and give wildlife the space it needs.