By the National Park Service Grizzly bears are active primarily during the night and at dawn and dusk. Look for grizzlies with binoculars or a spotting scope in open meadows around sunrise or sunset. Grizzlies are often seen from the road in the Lamar Valley, from Tower to Canyon, Lake, and Fishing Bridge. They are also seen along the road to the East Entrance. In the backcountry, grizzlies are most often seen south and east of Yellowstone Lake and in the Gallatin Mountains in the northwest corner of the park.
Black bears are active primarily during the day and at dawn and dusk.
Look for them in small openings within or near forested areas. Black bears are often seen along the road corridor from Mammoth to Tower and the Northeast Entrance, and in the Old Faithful, Madison and Canyon areas. Black bears are also seen in the remote southwestern corner of the park, the Bechler area. Many visitors remember the days when bears were commonly seen along the roads and within the developed areas of the park. Bears were attracted to these areas by the availability of human foods, either handouts or unsecured camp groceries and garbage.