The American pika (Ochotona princeps) is a small, round, brown mammal with large round ears and no visible tail. It is between six and eight inches long and weighs about six ounces. It can be found in western North America in rocky mountain areas and boulder-covered hillsides, usually at elevations of between 8,000-13,000 feet. They are territorial and eat a variety of green plants like grasses, sedges, thistles, and fireweed. Rocky Mountain National Park, CO.