American pika (Ochotona princeps)
The American pika (Ochotona princeps) is a small mammal that is closely related to rabbits. They live in mountainous alpine terrain above 11,000 feet, preferring to take shelter from weather and predators in talus, the rockfall at the foot of mountains. Some examples of pika habitat in the Greater Yellowstone Ecosystem are Death Canyon and the Gros Ventre landslide.
Pikas have large, rounded ears, a discreet tail, and a grey-brown coat. Adults grow to be about six inches long, so they are difficult to spot as they are well camouflaged in the talus. However, pikas are easy to hear because their loud, high-pitched call draws attention quickly and alerts others to hide from predators.
Each female pika can have anywhere from two to six pups per litter—possibly two litters a season—and they live anywhere from three to seven years. Their diet consists of wildflowers, sedges, and grasses. After July, feeding activity increases to benefit from the new plant growth. Since they do not hibernate, pikas stockpile food into haystacks to dry and later place it in their burrows for winter. These mammals can eat highly toxic plants! Pikas place the poisonous plants at the bottom of their stockpile because the toxins help preserve the other plants being stored, and the poisonous plant becomes tolerable over time.
Pikas are active in the early mornings and later in the day because they need colder temperatures to survive—six hours of exposure to temperatures over 80℉ will kill the mammal. Pika populations have declined because warming climate is a threat to the most sensitive species in the ecosystem. They move upslope to escape warmer temperatures, forced to abandon their lower elevation homes and start living at higher elevations. Sadly, there is only so much mountain to climb. That is why pikas are the “canaries” of climate change.
Written by Celia Karim
PC: YNP on Flickr: https://flic.kr/p/28ZLLDy
Sources: https://www.nps.gov/romo/learn/nature/pikas.htm, http://www.biologicaldiversity.org/species/mammals/American_pika/natural_history.html and Personal notes from ENR 1200 taught by Christopher Beltz, Fall 2016, University of Wyoming.