American pikas are medium-sized for pikas, weighing 121 to 176 grams. In some areas, males are a little bit bigger than females. Their bodies have oval shapes, their ears are short, their whiskers are long, their arms and legs are short, and they don't have a visible tail. The weight in their back paws in held up by their toes. Their back paws have four toes and are 25 to 35 mm long. Their front paws have 5 toes. American pikas have a high body temperature, about 104.2°F. However, if their body temperature goes above 109.6°F, they can't survive. They use energy quickly, so their metabolic rate is 1.53 cm^3 oxygen/hour. They keep themselves warm by sitting out in the sun or other behaviors instead of from inside their bodies. (Chapman and Flux, 1991; Smith and Weston, 1990; Wolf, et al., 2007)
The main fur color of American pikas changes each season, from grayish or cinnamon-brown in the summer to gray in the winter. It is also twice as long in summer. The fur on their bellies is off-white, rather than white like it is on collared pikas. They have round ears which are covered in dark hair and have white edges. They have very furry paws. They even have fur on the bottoms of their feet, except for black pads at the ends of their toes. Their skull is basically round but flat between the eyes, and their nose bone is thin. (Chapman and Flux, 1991; Smith and Weston, 1990; Wolf, et al., 2007)
American pikas live in the mountains in western North America. They live as far south as New Mexico and California, as far north as British Columbia, and as far east as Colorado. (Beever and Smith, 2008; Chapman and Flux, 1991; Fitzgerald, et al., 1994; Mains and Pigott, 2008; Smith and Weston, 1990; Wolf, et al., 2007)
American pikas live in places with broken rocks and rock bits along the edge of mountain meadows. They are most often found in cool, moist areas higher in elevation than trees can grow. Farther north, they are found from sea level up to 3,000 meters in elevation. Farther south, they almost always live above 2,500 meters in elevation. (Beever and Smith, 2008; Chapman and Flux, 1991; Fitzgerald, et al., 1994)
American pikas form pairs of one male and one female to mate. They choose mates from territories located next-door. If there is more than one option for a mate, females may get to choose. (Smith and Weston, 1990)
American pikas usually breed in their second year of life. Females have 2 sets of babies per year. Each set has about 3 babies. They start breeding 1 month before the snow melts and the young develop inside the body of their mother for about 30 days before they are born. They usually give birth in March at lower elevations, and in April or June at higher elevations. Pups weigh 10 to 12 grams when they are born. They drink their mother's milk for 28 days, which uses up a lot of the mother's fat. Females only give milk to a second group of offspring if the first don't survive. (Smith and Weston, 1990; Wolf, et al., 2007)
Baby American pikas are born blind and without much hair. Newborns weigh 10 to 12 g and have totally visible teeth. They are completely dependent on their mothers for the first 18 days. They open their eyes for the first time when they are 9 days old. Mothers spend most of their time looking for food. They stop hunting and go back to the nest for about 10 minutes every 2 hours. The babies are independent when they are 4 weeks old, right after they stop drinking their mother's milk. American pikas grow very quickly compared to other hares, rabbits, and pikas. They can become adult-sized when they are just 3 months old. (Smith and Weston, 1990; Wolf, et al., 2007)
The longest American pikas have ever lived in the wild and in captivity was 7 years. They usually live about 3 years. About 27 to 53% of them die in a year. They are most likely to die before they are 1 year old or after they are 5 years old. (Chapman and Flux, 1991; Fitzgerald, et al., 1994)
American pikas are active during the day and are active about 30% of the time when it's light outside. They spend time looking around for predators, eating and storing food, making noise, or establishing and maintaining their territories. They don't burrow but look for shelter in spaces between rocks. They do make tunnels through the snow during the winter to get access to meadows and haypiles. In fall and winter, they spend more time in their den and are less active. (Chapman and Flux, 1991; Fitzgerald, et al., 1994; Kawamichi, 1976; Smith and Weston, 1990; Wolf, et al., 2007)
The average area where American pikas travel and live is 816 to 2,182 sq m. Their breeding territories are usually about 410 to 710 sq m. (Smith and Weston, 1990)
American pikas use noises and scent marking to communicate. They can tell the difference between other individuals by calling and through chemicals given off from their cheek glands. The two noises they make most often are short calls and long calls. Short calls are an alarm when there are predators, or for defending their territory. Alarm calls are usually repeated short calls, and the frequency changes depending on the type of predator. Long calls are generally made by males in the breeding season. However, both males and females might make these noises in the fall. Mating pairs also perform duets of short calls. (Chapman and Flux, 1991; Fitzgerald, et al., 1994; Smith and Weston, 1990; Wolf, et al., 2007)
American pikas use scent marking, which means they communicate their territory by smell. They use urine, feces, and cheek marks to do this. Cheek marking comes from the parts of their bodies that make sweat, and also attracts mates. American pikas rub their lower jaws on rocks to cheek mark. They do this more often in the breeding season and when they establish themselves in a new territory. They also spread urine and feces on haypiles to show that they own them. (Chapman and Flux, 1991; Fitzgerald, et al., 1994; Smith and Weston, 1990; Wolf, et al., 2007)
American pikas eat many kinds of plants, and especially look for ones with high nutritional value. This means that they prefer plants with more protein, fats, water, and calories. They avoid plants with toxins, but might store them in hay piles to eat in the winter. Some toxins actually preserve the plant and wear off by the time it is eaten. They store food in summer in piles of flowering plants and tall grasses. They usually make these piles at the edge of rocks and meadows, and they also help mark their territory. When it turns to winter, they move haypiles into their burrows as their main food source. In the winter, they might also eat soft low-growing cushion plants and lichens. In the summer, they eat mostly short grasses. Flowering plants called forbs and and also shrubs make up 78 to 87% of their diet, and the rest is alpine avens, clovers, and sedges. Once in a while, they also eat pine needles or bark. They get most of the water they need from eating plants, so they don't have to drink water. (Chapman and Flux, 1991; Fitzgerald, et al., 1994; Smith and Weston, 1990; Wolf, et al., 2007)
American pikas have some camouflage. When they sense a possible predator, they give off an alarm call that warns the other American pikas about the predator. They don't do this as much for small predators, because small predators might be able to chase them into their hiding spots. Small predators that eat them are long-tailed weasels and stoats. Large predators like coyotes and American martens are very good at catching young who can't escape as quickly. They are also sometimes eaten by golden eagles. Other predators are bobcats, red foxes, northern goshawks, red-tailed hawks, marsh hawks, prairie falcons, and common ravens. (Fitzgerald, et al., 1994; Mains and Pigott, 2008; Smith and Weston, 1990)
American pikas change their environment through their activities. They make large haypiles of plants and feces. They don't use up all of them during the winter, so the rest turns into fertilizer or food for other animals. The fertilizer increases nitrogen in the soil, which is in short supply at high altitude. American pikas get many types of parasites in their intestines and also fleas on the outside of their bodies. (Aho, et al., 1998; Bossard, 2006; Lynch, et al., 2007)
There are no known negative effects of American pikas on humans.
There are no known positive effects of American pikas on humans.
American pikas live in a large area, and are not endangered according to the IUCN Red List. However, 7 of the 36 subspecies are listed as vulnerable. Another subspecies called White Mountains pikas are listed as near threatened. The 7 vulnerable subspecies live in the the Great Basin and have become locally extinct in some places. Some organizations say they should be protected by the Endangered Species Act. They would be better off if there were more protected areas or if they could be re-introduced where they have gone extinct. American pikas are most threatened by climatic change because they are super sensitive to high temperatures. If it gets warmer than 75°F, they can die within 1 hour. Many of them will probably move north or to higher elevation. (Beever and Smith, 2008; Blakemore, 2007; Wolf, et al., 2007)
Alexandra Peri (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), University of Michigan-Ann Arbor, John Berini (editor), Animal Diversity Web Staff, Catherine Kent (editor), Special Projects.
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