Black-tailed prairie dogs (Cynomys ludovicianus) are one of five prairie dog species that once ranged the Great Plains from southern Saskatchewan to northern Mexico. French explorers called them petits chiens, or "little dogs," because of their bark-like communication. These highly social animals are actually members of the rodent family. A type of ground squirrely, prairie dogs are closely related to other squirrels, chipmunks, woodchucks and marmots.
Prairie dogs are small, short-tailed animals with eyes and small ears set far back on their heads. Their light-brown fur blends well with the dirt of their mounds. Prairie dogs average 14 to 17 inches in total length and weigh 1 to 3 pounds. With short, muscular legs and long-nailed toes on their front and hind feet, they are well equipped for a burrowing lifestyle.
Prairie dogs live in lareg communities called towns. These towns consists of a large number of closely spaced burrows, each comprising an elaborate network of interconnecting tunnels and multiple entrance holes that provide escape routes from pursuing predators.
The primary prairie dog social unit is the coterie. A coterie typically consists of one adult male, several adult females, and their offspring. It can contain multiple burrows and be as large as one acre, depending on size of the total town.
Prairie dogs warn of territorial trespassers from adjacent coteries or approaching danger by emitting a series of "barks," which sound more like high-pitched squeaks. Specific threats are associated with distinctive vocalization patterns that serve to alert all residents of a town to the common threat.
Prairie dogs feed primarily on plants, selecting forbs and grasses high in moisture content and nutritive value to supply their needs for water and energy. Grasses quickly disappear from the town, which takes on a barren and overgrazed appearance. The open, closely-cropped terrain promotes easier social contacts and enables the collective "thousand eyes" of the residents to better spot approaching danger. Pronghorn, deer and other grazers are attracted to feed in this modified community, as the vegetation maintains a high nutrient content due to constant clipping. Predators also frequent the prairie dog town, as the rodents themselves offer an excellent found source for coyotes, foxes, hawks, badgers and more.
Prairie dogs build up large stores of body fat to carry them through the fall and winter months. Unlike most other members of their family, black-tailed prairie dogs do not hibernate. They may remain underground for several days during periods of harsh weather, but a return to milder winter conditions will find their towns bustling with activity.
Mating occurs from March to early April. After a month-long gestation period, the female bears a litter of one to six young. Born blind and hairless, the pups stay in the burrow for about six weeks while they develop fully. Emerging from the burrow, young prairie dogs are initially protected by their mothers. Weaning occurs shortly thereafter, when the pups have begun to forage for themselves. Most animals spend their brief five- to seven-year existence within the coteries of a single town.
Plump prairie dogs are an important component of the diet of many animals. Badgers, coyotes, foxes, bobcats, golden eagles. and various hawks all take their toll; rattlesnakes and bullsnakes occasionally prey on the young. Prairie dogs rely on their excellent hearing and vision to avoid these predators. From their vantage point atop the burrow mound, they can listen and scan the sky and prairie for danger. Upon spotting an enemy and announcing its presence to the rest of the town, the prairie dog dives into its burrow, emerging to give an "all clear" call when the danger has passed.
The prairie dog was once a major component of Great Plains life. Vast prairie dog towns stretched for miles across the open plains. In 1901, scientists surveyed a single Texas "dog town" that covered an area of 25,000 square miles and contained an estimated 400,000,000 prairie dogs. But this town and others were already under sentences of death. Prairie dog burrows proved dangerous for horses and wandering livestock and most ranchers were convinced that prairie dogs were destroying rangelands and competing with cattle for food. Extensive poisoning programs were implemented.
These measures virtually eradicated the prairie dog and many of its predators, chief among them the black-footed ferret. Formerly the prairie dog's most dangerous enemy, ferret numbers have only recently been raised through captive breeding programs to a level where small populations are now being released back into the wild. Today, scattered populations of prairie dogs are found mainly in protected areas such as state and national parks, monuments, grasslands, and wildlife refuges.