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Best Time to See Bears in Yellowstone

Bears in Yellowstone run on a clock set by food and snow: emerge in spring, gorge in fall, sleep through winter. Match their calendar and your chances of a sighting go up sharply.

Spring & Fall
two best windows
March 10
first grizzly (2018)
December 18
last grizzly (2018)
Sept–Oct
hyperphagia (feeding frenzy)

The two best windows

Spring emergence (late April–June)

As snow melts off the lower valleys, bears descend to dig for roots and hunt winter-killed animals. NPS first-sighting data shows grizzlies appearing as early as March 10:

YearFirst grizzlyWhere
2018March 10LeHardy Rapids
2019March 8Mud Volcano

Spring bears forage in the open meadows of Lamar and Hayden valleys, making this the most reliable viewing season.

Fall hyperphagia (September–October)

In hyperphagia, bears feed almost constantly to build winter fat. They’re active for long stretches across meadows and streams, which improves viewing — though you must keep extra distance from a food-focused bear.

How snowfall sets the schedule

Bear emergence tracks the receding snowline. The more snow, the later the green-up that draws bears down into the valleys. Here’s average monthly snowfall — note how it lingers into spring:

Jan: 10.8"Feb: 13.4"Mar: 10.3"Apr: 7.4"May: 2.2"Jun: 0.1"Jul: 0"Aug: 0"Sep: 0.5"Oct: 4.6"Nov: 12.1"Dec: 11.8"
JanFebMarAprMayJunJulAugSepOctNovDec
Average monthly snowfall, NOAA (Mammoth station).

⚠️Never feed or approach a bear

A fed bear is a dead bear. Bears that associate people with food become dangerous and are often euthanized. Keep all food stored, never approach for a photo, and maintain 100 yards at minimum. Carry bear spray.

By month: a quick guide

  • March–April: first grizzlies emerge; snow limits access.
  • May–June: peak spring viewing; cubs appear.
  • July–August: bears move high and into cover; harder to see.
  • September–October: hyperphagia; long active hours.
  • November: bears den up; viewing essentially over.

Frequently asked questions

What is the best time of year to see bears in Yellowstone?+

Two windows. Spring (late April through June) when bears emerge from dens and forage in lower, visible meadows. And fall (September and October) during hyperphagia, when bears gorge on nuts and carrion before denning and are active for long hours. Summer viewing is possible but harder as bears move to higher, brushier ground.

When do grizzly bears come out of hibernation in Yellowstone?+

Grizzlies begin emerging in early spring. In 2018 the first confirmed grizzly sighting was on March 10 at LeHardy Rapids; the first grizzly with cubs was seen on April 28. Males emerge first, followed by females without cubs, and finally females with new cubs.

When do bears go back into hibernation?+

Bears den up in late fall. The last confirmed grizzly sighting in 2018 was on December 18; the last black bear was seen on December 20. By November most bears are denned, though a few may be active into December in warm years.

What is hyperphagia and why does it matter for viewing?+

Hyperphagia is the intense feeding period in late summer and fall when bears consume up to 20,000 calories a day preparing for winter. Because they're actively feeding for many hours, they're more visible — but also more focused and protective of food sources, so keep extra distance and always carry bear spray.

Is fall bear viewing safe?+

It can be, with precautions. Hyperphagic bears are food-focused and can be less tolerant of approach. Stay at least 100 yards away, never get between a bear and a food source or escape route, make noise on trails, and keep bear spray accessible. Do not stop in the road or create a wildlife jam.

Sources & data notes

  • Emergence and denning dates: NPS Bear Management annual reports (2018, 2019).
  • Weather: NOAA NCEI GHCN-Daily, Mammoth station.
  • Hyperphagia and denning biology: NPS and IGBST grizzly ecology references.