They are sometimes called the “gray ghosts of the mountains.” Not a typical looking chipmunk (with white stripes along the length of their bodies to the head), cliff chipmunks have dark stripes extending from tail to the neck area, then with typical white stripes on the head. This elusive critter is somewhat secretive and fairly difficult to observe. It is quite likely you have never seen one in the wild. But, yes, these chipmunks do live in and among massive rock formations and cliffs in the Western U.S. Their tiny claws allow them to grasp minute irregularities in the surfaces of vertical cliffs which facilitates adroit climbing up and over perpendicular rock masses. They emit several kinds of vocal sounds: One is a “bock” sound, another is a high pitched chirp.
Cliff chipmunks are seed hoarders—they do not hibernate but remain intermittently awake during long wintertimes in their dens within cliff rock cavities. They “hoard” seeds during the summers, often placing newly gathered mature seeds in their internal cheek pouches, carrying them to small caches excavated in soil. Later in the summer or fall, they return and retrieve these seed caches, transporting them to their dens. During cold winters, they curl up and sleep much of the time, awakening every day or two to consume some stockpiled seeds. Such “hoarding” of seeds allows cliff chipmunks to survive during cold mountain winters lasting from November through February into March. New green food plants are generally not available until late April or May. As the snow begins to mostly melt in March, chipmunks search for seeds, new plant growth and other food items among last summer’s accumulation of leaves, rocks and other detritus in the hillsides above and below the cliffs.
One Study* observed various cliff chipmunks collecting seeds from over 30 different plants during a single summer. Of special interest was the ability of chipmunks to feed upon certain preferred, edible kinds of plants as these mature during the summer–stems, leaves and seeds until depleted. Then, they would move on to do the same with food parts of another kind of later maturing plant. It appeared that chipmunks feed freely on various plant parts, stems, leaves, blossoms, seeds, but the latter appears unique as quality high energy suitable for hoarding and storage. A variety of different food plants occurred randomly in the slopes above and below the rocky escarpments which the chipmunks visited depending upon availability and preference.
An actual strategy of how chipmunks feed are as follows: on tender leaf buds of Bigtooth maple (Acer grandidentatum) in May. Trees nearest the cliffs were foraged upon first. It was not uncommon for several animals to feed simultaneously in the same tree at the same time. Towards the end of May, serviceberry (Amelanchier utahensis) buds were the food of choice with berries eaten later in the summer. In June, chipmunks were found feeding upon Arrowleafed balsamroot (Balsamorhiza sagittata) leaves, stems, and seed heads. Typically, the stem was cut and seeds eaten, leaving a tell-tale pile of seed hulls. This plant was fairly widespread over the entire study area. In June, bluegrass seeds (Poa spp.) and wild carrot stem and seeds (Lomatum disectum) were utilized. Salsify (Tragopogon dubius) matured in late June and July. Seed heads and leaves were preferred. In late June and July, bitterbrush (Purshia tridentata) matured and was eaten for the rest of the summer in a number of locations. Bitterbrush seeds appeared to be a major contributor to the winter seed stockpile. Elk thistle (Cirsium spp.) matured in late July. The prickly parts did not seem to deter chipmunks from consuming seed heads. This plant grew singly and was not numerous either above or below the cliffs.
Various plants utilized for food are scattered throughout the area. These are utilized as they become viable food sources for chipmunks and other wildlife.
Hart, E. B. 1971. Food preferences of the cliff chipmunk, Eutamias dorsalis, in northern Utah. Great Basin Naturalist, Vol 31(3): 182-188.
About Cliff Chipmunks, Tamias dorsalis:
Mature cliff chipmunks are typically the size of a small rat. Their mannerisms are similar to other chipmunks of the genus. They normally produce one litter per year (4-6 young) in the northern parts of their distribution. Gestation is from 28 to 31 days. Home range may be as much as 4 Ha (9 acres) and less. Natural predators include small carnivores, avian raptors and snakes. Ectoparasites include fleas, lice, mites, botfly larvae; probably some endoparasites are present in some populations.