Common name: Black-tailed prairie dog
Scientific name: Cynomys ludovicianus
Other names: Petit chien, barking ground squirrel, prairie marmot, prairie squirrel, pispiza
Identification: Reddish-brown fur throughout the body with lighter color on the underside. Last 1/3 of the tail is black.11-13 inches (28-33 cm) long plus a 3-4 inch (8-10 cm) tail. Males are generally larger than females. Black-tailed prairie dogs weigh 2-3 lbs. (900-1,360 g).
Habitat: Prairies, grasslands and open areas with clay soils that can maintain a burrow system. Mostly level ground so they can see predators approaching.
Food: Grass. Western wheatgrass, blue grama, buffalograss, scarlet globemallow.
Reproduction: Takes place below ground February-April, depending on latitude. Female is receptive for only a few hours one day per year. Gestation 34-35 days. Litter sizes can range from 1-6 pups (average 3). Mothers will lactate and nurse for 37-51 days. Juveniles will emerge above ground May-June and become mature at 2 years old. One litter per year.
Behavior: Black-tailed prairie dogs are social and live together in large aggregations called colonies or towns. Within a colony a family unit of prairie dogs, known as a coterie, consists of 1 adult male, 2-3 adult females and all of their young less than 2 years old. Coteries can number 1-26 individuals (average 6) and occupy an area up to 2.5 acres (1 hectare) but typically average 1 acre (0.4 hectares) in size. Black-tailed prairie dogs defend the boundaries of the coterie from other prairie dogs and most coteries contain 70+ burrow entrances. Within the coterie prairie dogs will “kiss” (touch their front teeth together) to recognize their kin.
Prairie dogs are diurnal (active during the day) and spend most of their time feeding, maintaining burrows and clipping vegetation to see approaching predators (coyotes, hawks, badgers, eagles).The main sources of mortality are predation, infanticide (a female prairie dog killing another female prairie dogs pups), inability to survive winter and plague. Black-tailed prairie dogs can live as long as 5-8 years but on average live 2-5 years. Surviving the first year is difficult. Females typically spend their entire life in the coterie they were born whereas males will disperse away from their natal coterie.
When a potential predator approaches the colony prairie dogs will begin to “bark” an alarm call to alert other prairie dogs of the danger. Black-tailed prairie dogs have at least a dozen different vocalizations including the “jump-yip” where the prairie dog throws it’s front legs into the air and makes a “Whee-ooo” sound. Black-tailed prairie dogs typically do not hibernate but if conditions are extreme (drought, extreme cold, deep snow) they can go into hibernation (facultative torpor).
Conservation status: Black-tailed prairie dogs were poisoned, plowed over and shot throughout most of the 20th Century. Plague has also been a significant factor in prairie dog decline. At one time there was an estimated 79 million acres (32 million hectares) of black-tailed prairie dog colonies in North America. Today there are an estimated 2.4 million acres (983,000 hectares) occupied, a 97% reduction in the past 150 years.
Black-tailed prairie dogs were petitioned for listing under the Endangered Species Act in 1994 but not enough information was available and listing was denied in 1995. In 1998 they were again petitioned to be listed as threatened species and were placed on the candidate (should be listed but will not be because of higher priorities) list in 2000. In 2004 the black-tailed prairie dog was removed from the candidate list. The US Fish & Wildlife Service again evaluated black-tailed prairie dogs for listing in 2008 but denied listing in 2009. In some US States prairie dogs are managed to a certain degree but are listed as a pest in other states. Black-tailed prairie dogs were extirpated from Arizona by 1940 but recently Arizona has reintroduced populations. Some US States have state laws or local ordinances that nearly mandate the eradication of prairie dogs. In Canada black-tailed prairie dogs are listed as a species of Special Concern under the Species at Risk Act (SARA).
Today the primary threats to black-tailed prairie dogs are plague and negative public attitudes. Even on federal public lands it is difficult to maintain prairie dogs because of political pressure to poison from agricultural interests. Those prairie dogs that do remain are susceptible to plague.