268 Ictidomys mexicanusIctidomys mexicanus (Erxleben, 1777)
Mexican Ground Squirrel
description: Mexican ground squirrels have an oliva-
ceous gray to sepia brown back, with nine rows of white to
buff spots from the back of the head to the rump. The snout
and chin are yellowish to ochre to cinnamon. The white to
buff eye ring is conspicuous. The sides and venter are buff
to yellow. The tail is grizzled black, suff used and frosted
with the coloration of the venter.
size: Both sexes—TL 322–380 mm; T 124–166 mm; Mass
217–398 g.
distribution: This species is found in central México, in
Aguascalientes, Jalisco, Guanajuato, Querétaro, Hidalgo, Mé-
xico D.F., Tlaxcala, and Puebla.
geographic variation: None.
conservation: IUCN status—least concern. Population
trend—stable.
habitat: Mexican ground squirrels inhabit grassy pastures
and meadows, grassy shrublands and savannas, and arid
regions.natural history: This species is diurnal. Mexican ground
squirrels hibernate in burrows for 5–6 months, beginning in
September (males) or October (females) through March or
April. Males emerge fi rst in late March, and females two to
four weeks later. Mating occurs in the spring. A litter aver-
aging four (range = 3–5) young is born in a burrow. Nursing
females are found in the population from June to Septem-
ber; males with scrotal testes occur from March to July. Ju-
veniles enter hibernation in late October and November.
Numerous short burrows are used for temporary or escape
cover, and they often appear to be the burrows of pocket
gophers (Thomomys). Burrows for residence are less than
1.5 m long and can have one or more nest chambers within
the labyrinth of tunnels. Colonies of many individuals oc-
cur in favorable habitat; however, levels of sociality are low.
I. mexi canus is an omnivore that feeds heavily on the leaves,
shoots, fl owers, and seeds of grasses, forbs, shrubs, and
cacti, but it will a lso consume signifi cant amounts of insects
and other animal matter when available, especially beetles in
the spring. Most small carnivores—including felids, canids
and mustelids, raptors, and snakes—prey on I. mexicanus.
Their alarm call is a shrill whistle. Mexican ground squir-
rels are not hunted for food or pelts; however, they are shot
or poisoned as a local nuisance.Ictidomys J. A. Allen, 1877
This genus comprises three ground squirrel species.
Ictidomys mexicanus. Photo courtesy Juan Cruzado.