Tiny But Tough: The American Pika
"Fieldnotes," October 20th & 21st, 2013: "American Pika," by Jessie Grossman and Allison de Jong. http://www.montananaturalist.org/
"In Montana, wolverines get most of the glamour as a no-nonsense creature of extremes, but fluffy pikas are in the running with their affinity for the harsh alpine climes of Montana's Rocky Mountains. While pikas are tiny but tough, there are some things they can't defend themselves against. One of these threats is warm temperatures. Pikas can die in what, to humans, seems like mild weather - as low as 78 degrees F - which is why they rarely venture into lower elevations. Global climate change threatens pikas and the cold mountainous habitat they depend on."