Pikas are small, elusive mammals inhabiting rugged, high-altitude environments. These creatures have adapted to challenging landscapes, thriving where few other animals can. Their presence often indicates a healthy mountain ecosystem. This article explores the characteristics, habitats, and behaviors that define these unique alpine residents.
Defining Characteristics
Pikas are small, stout-bodied mammals, typically measuring between 15 to 23 centimeters (6 to 9 inches) in length and weighing 120 to 350 grams (4 to 12.3 ounces). They are often mistaken for rodents due to their size, but pikas belong to the order Lagomorpha, making them relatives of rabbits and hares. Unlike their larger cousins, pikas possess short, rounded ears and lack a visible external tail, giving them a distinct, compact appearance.
Their dense fur, usually grayish-brown, provides insulation against the cold mountain air and helps them blend well with their rocky surroundings. While their fur thins slightly in summer, it remains thick enough to pose a risk of overheating in prolonged high temperatures. Pikas also have fur-covered paws, including their soles, which aids in traction and warmth on uneven, cold terrain.
Their Mountain Home
Pikas are primarily found in mountainous regions across North America and Asia, with approximately 30 species distributed globally. In North America, the American pika and collared pika inhabit high-elevation cool mountains, particularly west of the Rocky Mountains, extending from British Columbia to New Mexico. They thrive in specific habitats characterized by rocky slopes, talus fields, and scree, which are accumulations of broken rock debris, often situated above the tree line.
These environments provide crevices among the rocks, which pikas utilize for shelter and protection from predators. While they generally prefer elevations between 2,500 to 4,000 meters (8,000 to 13,000 feet) in southern parts of their range, some populations exist at lower altitudes. Their adaptation to cold conditions makes them sensitive to warmer temperatures, preferring cool, moist microhabitats.
Life in the Wild
Pikas are herbivores, consuming a varied diet of mountain vegetation, including grasses, wildflowers, sedges, moss, and lichens. They are known for their unique “hay stacking” behavior, where they collect vegetation during the summer months. These collected plants are laid out to dry in the sun, preventing mold, before being stored as “haypiles” within their rocky dens for sustenance during the winter.
Unlike other mountain mammals, pikas do not hibernate; they remain active throughout the year, relying on their stored food and foraging when weather permits. They are diurnal, active during the day, and often heard before they are seen. Pikas communicate through high-pitched calls, which serve as alarm signals to warn others of predators such as weasels, hawks, and coyotes. While they live in colonies, individual pikas are territorial, defending their den and surrounding foraging areas with vocalizations and displays.
Pikas and a Changing World
Pikas are susceptible to rising temperatures, making them an important indicator species for climate change in alpine environments. They have a high resting body temperature and can suffer from heat stress, with exposure to temperatures above 25.5°C (77.9°F) for even brief periods proving lethal. As global temperatures increase, pika populations in some areas have experienced declines and shifts to higher altitudes.
Upward migration often presents limited options, as suitable high-elevation habitats are finite. Reduced snowpack, a consequence of warming climate, also poses a threat. Pikas depend on a stable snow layer to insulate their rocky dens from winter cold, and inadequate snow cover can expose them to freezing temperatures. While many pika populations across their core range appear resilient, local losses highlight concerns about their long-term survival in a changing world.