Prairie dogs are named for the dog-like yip they make, but in fact are fairly big, stout, ground-dwelling squirrels. Black-tailed prairie dogs are generally pinkish-brown to tan on their upper parts and buff to whitish on their lower parts. Their name comes from the distinctive black tip on their short tail. The color of their coat varies slightly as the seasons change, their body hair tipped with black in winter and white in summer. There are no strong different characteristics that separate the genders, although males are usually heavier than females.
Black-tailed prairie dogs occur in the extreme south of central Canada, throughout the United States, and in north-eastern Mexico. They inhabit a fairly limited range of open, arid, level, short-grass prairies. They are often found near river flats and in coulee bottomlands where greasewood, sagebrush, and prickly pear grow. These animals never inhabit moist areas.
Prairie dogs live in towns or colonies, sometimes numbering hundreds, living within a very small area. The town has certain neighborhoods, or coteries. The females usually stay in their natal coterie, while males disperse to a coterie nearby. Each coterie contains a group of females who are closely related (mothers, sisters and aunts) and one or perhaps two territorial males. In the breeding season, females will aggressively defend their burrow against other females and sometimes even raid burrows of other female prairie dogs and kill their pups. These animals are diurnal and are active throughout the year. They do not hibernate, unlike many other prairie dog species. When active above ground, they engage in a range of behavior, such as moving dirt to enhance burrow entrances, gathering nesting material, and scratching to cope with fleas.
Black-tailed prairie dogs are typically polygynous (or harem-polygynous); a single male will mate with multiple females from his home coterie. In some cases, though, there may be more than one male living in one large coterie. In such a case, a female in the coterie may breed with both of the resident males, which indicates a polygynandrous (promiscuous) mating system. Mating occurs between January and April, according to the latitude. One to eight pups per litter (3-4 on average) are born following gestation of between 33 and 38 days. Pups are born naked with their eyes closed, and stay in their burrow for around six weeks. They are weaned at about seven weeks but stay near to their mother for two more weeks. Females stay in their natal coterie for the rest of their lives, but males disperse when they become yearlings. Black-tailed prairie dogs reach sexual maturity at about 1-3 years old.
The numbers of Black-tailed prairie dogs have decreased due to habitat destruction as a result of development and agriculture. Widely considered a pest for destroying cultivated crops, they are exterminated through shooting and poisoning. Sylvatic plague-a disease that arrived in North America in 1900-also threatens the prairie dogs’ survival. These animals do not seem to have an immunity to plague, which now has impacted almost every area where they live. Plague often kills most if not all individuals in an area within a few days.
According to the IUCN Red List, the total Black-tailed prairie dog population size is around 18,420,000 individuals. Currently this species is classified as Least Concern (LC), but their numbers today are decreasing.
Black-tailed prairie dogs have a number of essential roles in their ecosystem. This species modifies the vegetation in the area, aerates the soil and provides food as well as shelter for a variety of predators, including mammals, snakes, and birds of prey. Being primary consumers, they provide a vital link in food webs.