Hopi chipmunks are small in size compared to other species and their dorsal pelage generally lacks significant amounts of black in the stripes. The color of their coat is more orange-red to buff. Females in this species are slightly larger than males.
Hopi chipmunks are found in Colorado, Utah and Arizona in the southwestern United States. In Colorado, they occur in the west from the Yampa River south. They range eastward along the Colorado River to Eagle County and along the Gunnison to the western end of the Black Canyon. Hopi chipmunks prefer rocky areas with pinion and juniper pines and inhabit areas with an abundance of broken rock or rubble at the base of cliff faces or in rock formations with deep fissures and crevices suitable for den sites.
Hopi chipmunks are diurnal and active in the morning and in the afternoon, especially in summer as they try to avoid midday heat. These animals lead a solitary life and may show dominance when other chipmunks enter their territory. Hopi chipmunks hibirnate before their breeding season from late November until February. They nest in rock crevices or piles of broken rock. Hopi chipmunks are fast and sure-footed on the sheer rock faces of canyons and buttes. They often climb into shrubs to get seeds, but never eat there: either they take the food to the safety of their den, or perch on a boulder or other lookout where they can eat but at the same time watch for hawks or other predators. In order to communicat with each other Hopi chipmunks produce two main calls: alarm calls and courtship sounds. Alarms calls include a chip, chuck, or "chippering" sound, trills and whistles.
Little is known about the mating system in Hopi chipmunks. The breeding season for these animals lasts from February until mid-April. Females give birth to one litter that consists of 4 to 7 young. The Gestation period lasts around 30-33 days. Young are born altricial and weigh about 3 grams at birth. Pups stay in nests until they are grown enough to become independent from their mother. At 5 weeks after birth, young become active outside and at 6 weeks, they start consuming solid foods. Weaning usually occurs when pups are 6 to 7 weeks old and by then they become independent. Hopi chipmunks reach reproductive maturity at 10 to 12 months on average and most females are able to have first litter in their first year.
There appear to be no major threats to Hopi chipmunks at present.
According to IUCN, the Hopi chipmunk is locally common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today remain stable.