Black-tailed Prairie Dog

activity

Activity patterns. Black-tailed Prairie Dogs are diurnal and can be active throughout the year, except during periods of prolonged cold when individuals can enter torpor and remain underground. Adults are readily active aboveground by March or early April and may begin to reduce aboveground activity in July-August in some areas; juveniles remain active until October-November.

Sciuridae

biology_ecology

Habitat. Open flat to gently sloping grasslands with low and relatively sparse vegetation, in areas with fineto medium-textured soils. In the east, tall grass prairies where vegetation height is maintained by mowing or grazing are commonly used; in the west, short-grass and mixed-grass prairies are primary habitats. The Black-tailed Prairie Dog can use overgrazed livestock range, airports, and vacant grasslands at edges of urban areas.

Sciuridae

biology_ecology

Movements, Home range and Social organization. The Black-tailed Prairie Dog is highly social and lives in large complexes called “ towns ” or colonies. Burrows are relatively complex with multiple entrances and are recognizable by a small mound ofsoil and barren ring around entrances. A nest is found at the end of burrows that exceed 10 - 15 m long and penetrate 2 - 3 m deep. Black-tailed Prairie Dog colonies vary considerably in size and density, but some are known to extend for many kilometers, sometimes 35 km in length or longer especially prior to western European settlement and persecution. Colonies consist of territorial family groups called coteries. Coterie size can be as small as two or as large as 26 individuals, but the typical coterie contains one adult male, 2 - 3 adult females, and 1 - 2 yearlings of both sexes. Coterie territories average c. 0 - 3 ha, and their boundaries remain remarkably stable over time. A typical coterie has c ¢. 70 burrows, and all members of a coterie can use any of these entrances, with one exception: pregnant and lactating females vigorously defend nursery burrows. Females in a coterie are almost always close kin (mothers, daughters, sisters,

Sciuridae

breeding

Breeding. The Black-tailed Prairie Dog lives in multi-burrow colonies. Mating season lasts 2 - 3 weeks when females enter a single day of estrus and copulate in burrows. Multiple paternities occur and a first-male advantage exists for sires. Reproductive maturity is reached at c. 2 years old; however, a few females and males produce as yearlings. Young are born in burrows after 34 - 35 days of gestation. Females can wean onelitter per year; although most adult females mate, c. 90 % wean a litter, and ¢. 50 % ofyearling females are successful. Litters of 1 - 6 young appear aboveground at c. 6 weeks after birth and are weaned soon afterward. Natal dispersal is male-biased, with most males dispersing in late spring or early summer of their yearling year; breeding dispersal by older adult malesis also common. Mean lifetime reproductive successis higher in males (c. 7 weaned offspring) than females (c. 4 weaned offspring), but it is more variable for males. Female reproductive success is positively impacted by previous year’s rainfall and by breeding early in the season. Heavy long-lived individuals have the highest lifetime reproductive success.

Sciuridae