260 Cynomys gunnisoniCynomys gunnisoni (Baird, 1858)
Gunnison’s Prairie Dog
description: Gunnison’s prairie dog is buff to pale yellow
on the dorsum, grizzled with small amounts of black. The
underside is white to cream, with a gradual transition from
the darker dorsum. The head is colored similarly to the dor-
sum, but it is often cream to white and lighter than the rest
of dorsum; there is often a faint black patch between the
eyes and the sides of the snout. The tail fades to a pale buff
or white tip. C. gunnisoni is the smallest of the prairie dogs.
size: Female—TL 325 mm (309–338 mm); T 54 mm (46–
61 mm); Mass 644 g (465–750 g).
Male—TL 335 mm (317–390 mm); T 51 mm (40–60 mm);
Mass 816 g (460–1300 g).
Males are about 136 percent of female mass at hiber -
nation.
distribution: Gunnison’s prairie dog is found in south-
eastern Utah, southwestern Colorado, northeastern Ari-
zona, and northwestern New Mexico (USA).
geographic variation: Two subspecies are recognized.C. g. gunnisoni—eastern portion of the range. This form is a
slightly smaller, paler, and buff -colored montane form.
C. g. zuniensis—western portion of the range. It is a slightly
larger, darker, and more cinnamon-colored grassland
form.conservation: IUCN status—least concern. Population
trend—decreasing.habitat: Gunnison’s prairie dogs inhabit high-elevation
open mountain valleys and plateaus, but they can thrive in
modest shrub and open pinyon-juniper (Pinus, Juniperus)
savannas.natural history: This species is diurnal. It hibernates in
burrows for up to fi ve months in many parts of its range,
typically from late October to February. The burrows are
generally 2–3 m deep and average as much as 13 m long, with
multiple entrances (generally three to four entrances per
burrow, but sometimes up to six). Females attain sexual ma-
turity and mate as yearlings; each fema le can wean only one
litter per year. Males sometimes mate as yearlings, but they
commonly delay their fi rst mating until they are 2 years old.
The seasonal timing of reproduction varies with latitude
and elevation. Females usually mate within several days of
their emergence from hibernation. One litter is produced
each year (in the spring), with the young born in the burrow
after a gestation of 28–30 days. Multiple paternity of litters is
frequent, approaching 80 percent. The young remain below-Cynomys Rafinesque, 1817
This genus contains fi ve species of prairie dog.
Cynomys gunnisoni. Photo courtesy Doris Potter / Focus on Na-
ture Tours, Inc.