Prairie dogs are herbivorous burrowing mammals native to the grasslands of North America. Within the genus are five species: black-tailed, white-tailed, Gunnison's, Utah, and Mexican prairie dogs. In Mexico, prairie dogs are found primarily in the northern states, which lie at the southern end of the Great Plains: northeastern Sonora, north and northeastern Chihuahua, northern Coahuila, northern Nuevo León, and northern Tamaulipas. In the United States, they range primarily to the west of the Mississippi River, though they have also been introduced in a few eastern locales. They are also found in the Canadian Prairies. Despite the name, they are not actually canines but "...a species of squirrel rather than a dog." Prairie dogs, along with the marmots, chipmunks, and several other basal genera belong to the ground squirrels (tribe Marmotini), part of the larger squirrel family (Sciuridae).
Prairie dogs are considered a keystone species with their mounds often being used by other species. Their mound-building encourages grass development and renewal of topsoil, with rich mineral, and nutrient renewal in the soil which can be crucial for soil quality and agriculture. They are extremely important in the food chain, being important to the diet of many animals such as the black-footed ferret, swift fox, golden eagle, red tailed hawk, American badger, and coyote. Other species, such as the golden-mantled ground squirrel, mountain plover, and the burrowing owl, also rely on prairie dog burrows for nesting areas. Grazing species, such as plains bison, pronghorn, and mule deer have shown a proclivity for grazing on the same land used by prairie dogs. Prairie dogs have some of the most complex systems of communication and social structures in the animal kingdom.
The prairie dog habitat has been affected by direct removal by farmers, as well as the more obvious encroachment of urban development, which has greatly reduced their populations. The removal of prairie dogs "causes undesirable spread of brush", the costs of which to livestock range and soil quality often outweighs the benefits of removal. Other threats include disease. The prairie dog is protected in many areas to maintain local populations and ensure natural ecosystems and that they are not harmed.
Prairie dogs live mainly at altitudes ranging from 2,000 to 10,000 ft above sea level. The areas where they live can get as warm as 38 °C (100 °F) in the summer and as cold as −37 °C (−35 °F) in the winter. As prairie dogs live in areas prone to environmental threats, including hailstorms, blizzards, and floods, as well as drought and prairie fires, burrows provide important protection. Burrows help prairie dogs control their body temperature (Thermoregulation) as they are 5–10 °C (41–50 °F) during the winter and 15–25 °C (59–77 °F) in the summer. Prairie dog tunnel systems channel rainwater into the water table which prevents runoff and erosion, and can also change the composition of the soil in a region by reversing soil compaction that can result from cattle grazing.
Prairie dog burrows are 5–10 m (16–33 ft) long and 2–3 m (6.6–9.8 ft) below the ground. The entrance holes are generally 10–30 cm (3.9–11.8 in) in diameter. Prairie dog burrows can have up to six entrances. Sometimes the entrances are simply flat holes in the ground, while at other times they are surrounded by mounds of soil either left as piles or hard packed. Some mounds, known as dome craters, can be as high as 20–30 cm (7.9–11.8 in) high. Other mounds, known as rim craters, can be as high as 1 m (3 ft 3 in). Dome craters and rim craters serve as observation posts used by the animals to watch for predators. They also protect the burrows from flooding. The holes also possibly provide ventilation as the air enters through the dome crater and leaves through the rim crater, causing a breeze though the burrow. Prairie dog burrows contain chambers to provide certain functions. They have nursery chambers for their young, chambers for night, and chambers for the winter. They also contain air chambers that may function to protect the burrow from flooding and a listening post for predators. When hiding from predators, prairie dogs use less-deep chambers that are usually one meter (3 ft 3 in) below the surface. Nursery chambers tend to be deeper, being two to three meters (6 ft 7 in to 9 ft 10 in) below the surface.