Craig Pass Closed for the Season; Mammoth to Norris Closed Sept. 14-30
The road linking West Thumb and Old Faithful is closed for the season—traffic should detour through West Thumb, Lake, and Canyon. The road from Mammoth to Norris is closed for two weeks—traffic should detour over Dunraven Pass. More »
Pikas (Ochotona princeps) are small territorial mammals about the size of guinea pigs. They inhabit rocky alpine and sub-alpine zones feeding on the vegetation that fringes their preferred talus slopes. Colored gray to brown with round ears and no tail, they blend in with their rocky home and agilely maneuver between and underneath obstacles. Because pikas do not hibernate, this relative of the rabbit must gather enough plant materials during the short growing season to survive the winter. Piles of drying vegetation, called haystacks, and a distinctive high-pitched call are the most recognizable indicators of active pika habitat. Prolific breeders, pikas usually have two litters of young each summer. The mortality rate is high for the youngsters and the first litter has a greater rate of survival. These small mammals are sensitive to temperatures above 77.9°F; therefore, they are most active during cooler parts of the day.
Quick Facts about Pikas
Did You Know?
Lake trout are an invasive species of fish that is decimating the native cutthroat trout population in Yellowstone Lake.