Tamias quadrivittatusColorado chipmunk

Geographic Range

Tamias quadrivittatus is found in east to southeastern Utah, throughout Colorado, northeastern Arizona and northern Utah. (Bergstrom, 1988; "Tamias quadrivittatus", 2002; Sullivan, 1996; Whitaker Jr., 2002)

Habitat

Colorado chipmunks are most common in ponderosa forest but may also be abundant in mixed coniferous forest and woodland. A few are found in spruce-fir areas, but Tamias minimus is the more common chipmunk there. At lower elevations, in scattered pinyon-juniper woodland, T. quadrivittatus. may be fairly common, especially if rock outcrops are available. In the Organ mountains, the southern subspecies of the Colorado chipmunk is most common around Aguirre Springs at elevations ranging between 1845 and 2225 m. The species also occurs in the Oscura Mountains at elevations ranging from 2393 to 2500 m, where vegetation is believed to be similar to the Organs. ("Tamias quadrivittatus", 2002; Fitzgerald, et al., 1994; Sullivan, 1996)

These chipmunks are strong tree-climbers, but they spend most of their time among fallen logs, rock piles, and on the ground. They may be found among rock outcrops to elevations nearly in the spruce-fir forest. In Utah, these chipmunks have been found in association with broken rock or rock crevices in the pinyon-juniper community. ("Tamias quadrivittatus", 2002; Fitzgerald, et al., 1994; Sullivan, 1996)

  • Range elevation
    1845 to 2500 m
    6053.15 to 8202.10 ft

Physical Description

Colorado chipmunks are medium-sized chipmunks, with amass of about 54 g, and a length averaging 121 mm. (Patterson, 1984; Sullivan, 1996)

The pelt is mostly orange, although the head is cinnamon colored, with shades of gray with white color on the belly, and yellowish-brown on the sides. These animals have 3 median stripes on their backs, which are black with yellowish-orange margins, and have outer stripes that are brown. Shoulders are gray, the thighs and rump are cinnamon. The tail is black tipped, white-bordered, and tawny underneath. Their ears are blackish in front, whitish behind. (Patterson, 1984; Sullivan, 1996)

Distinction from similar species (Tamias rufus) can be found in the baculum size. Studies have shown that the baculum is larger in dimensions in T. quadrivittatus. (Patterson, 1984; Sullivan, 1996)

  • Sexual Dimorphism
  • sexes alike
  • Average mass
    54 g
    1.90 oz
  • Average mass
    70 g
    2.47 oz
    AnAge
  • Average length
    121.9 mm
    4.80 in

Reproduction

Colorado chipmunks are monogamous. (Whitaker Jr., 2002)

Breeding takes place in spring. Gestation lasts between 29 and 60 days. One litter of 2 to 7 young is produced and the young will be fully grown by July to August. Presence of some small young in October may indicate an occasional second litter, although one litter per year is thought to be more typical. ("Tamias quadrivittatus", 2002; Hoffmeister, 1986; Whitaker Jr., 2002)

  • Breeding interval
    These animals generally breed once per year.
  • Breeding season
    Breeding occurs in the late winter.
  • Range number of offspring
    2 to 7
  • Average number of offspring
    4.4
    AnAge
  • Range gestation period
    1 to 2 months
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    319 days
    AnAge
  • Range age at sexual or reproductive maturity (male)
    4 to 5 months

No information on the parental care of this species was found. However, in general, ground dwelling sciurids are altricial. They are born in the burrow, where the mother cares for them, providing them with milk, grooming, and protection, until they are capable of dispersing. Although no information is available, because this species is monogamous, it is possible that the male plays some role in the parental care.

  • Parental Investment
  • no parental involvement
  • altricial
  • pre-fertilization
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • protecting
      • female

Lifespan/Longevity

Longevity of this species has not been reported.

Behavior

Tamias quadrivittatus is active in the early morning and late afternoon. They give a short bark to warn when they are alarmed. They are more arboreal than most chipmunks, and they tend to occupy coniferous areas. (Bergstrom, 1988; Whitaker Jr., 2002)

They have been spotted eating seed at the tops of spruce trees. In Colorado, this chipmunk is often associated with the more abundant species T. minimus, which occupies meadows. In New Mexico, T. quadrivittatus occurs at higher elevations, in areas of ponderosa pine, Douglas fir, and aspen, and cliff chipmunks occur in lower elevation areas with pinyon-pine and juniper woods. (Bergstrom, 1988; Whitaker Jr., 2002)

Tamias quadrivittatus maintains male-female pairs during the breeding season. They forage near their burrows, returning frequently to their nesting sites to cache food. They are generally active by day. During winter months they retreat to nests in trees, logs, or underground burrows to hibernate. (Bergstrom, 1988; Whitaker Jr., 2002)

Home Range

Home range for adult females is 2.6 acres; and for adult males the range is 3.2 acres. The home range of juveniles is anywhere from around 1 to 2.5 acres. ("Tamias quadrivittatus", 2002; Hoffmeister, 1986)

Communication and Perception

Colorado chipmunks are reported to give alarm calls. (Whitaker Jr., 2002)

In addition to accoustic communication, as diurnal mammals, members of this species are likely to use some visual communication, such as body postures. Tactile communication undoubtedly occurs between mates, parents and their offspring, and rivals. There are probably some chemical cues used also.

Food Habits

Colorado chipmunks are herbivorous. Their diet consists of seeds and berries, but they will also feed on insects, bird eggs, and carrion. Seed and berry types include ricegrass, juniper, cliffrose, skunkbush, mountain mahogany, and squawberry in July and August; Russian thistle, pinyon, oak, and Indian ricegrass in September and October. They are known to cache their food. With good climbing ability, T. quadrivittatus will search in between rocks, bushes and in trees for food. They depend upon free water sources. (Armstrond, 1972; "Tamias quadrivittatus", 2002)

  • Animal Foods
  • eggs
  • carrion
  • insects
  • Plant Foods
  • leaves
  • roots and tubers
  • wood, bark, or stems
  • seeds, grains, and nuts
  • fruit

Predation

Raptors, including northern goshawks, are the main predators of Colorado chipmunks. ("Tamias quadrivittatus", 2002)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Colorado chipmunks are important seed dispersers and are food for various raptors. ("Tamias quadrivittatus", 2002)

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

Although very cute animals, Colorado chipmunks are not known to have a direct economic importance to humans. However, through their seed caching, they help the growth of plants which normally have difficulty germinating on the surface.

Economic Importance for Humans: Negative

These animals are not directly harmful to the economic activities of humans. However, if populations are large, they may impact forest regrowth by eating seeds.

Conservation Status

Colorado chipmunks are not listed by CITES or IUCN.

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Matt Hamilton (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor, instructor), University of Wisconsin-Stevens Point.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

arboreal

Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carrion

flesh of dead animals.

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

hibernation

the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

stores or caches food

places a food item in a special place to be eaten later. Also called "hoarding"

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

References

Biota Information System Of New Mexico (BISON). 2002. "Tamias quadrivittatus" (On-line ). Accessed 11/04/02 at http://www.cnr.vt.edu/fishex/nmex_main/species/050145.htm.

Armstrond, D. 1972. Distribution of Mammals in Colorado. University of Kansas Museum of Natural History, 3: 415.

Bergstrom, B. 1988. Home Ranges of Three Species of Chipmunks(TAMIAS) as assessed by Radiotelemerty and Grid Trapping. Journal of Mammalogy, 69(1): 190-193.

Fitzgerald, J., C. Meaney, D. Armstrong. 1994. Mammals of Colorado. Denver Museum of Natural History and University Press of Colorado: 467.

Hoffmeister, D. 1986. Mammals of Arizona. The University of Arizona and Press and the Arizona Game and Fish Dept: 602.

Patterson, B. 1984. Geographic Variation and taxonomy of Colorado and Hopi Chipmunks (Genus Eutamias). Journal of Mammalogy, 65: 442-456.

Sheppard, D. 2002. "Chipmunk" (On-line ). Canadian Wildlife Service. Accessed 11/04/02 at http://www.ec.gc.ca/cws-scf/hww-fap/chipmunk/chipmunk.html.

Sullivan, R. 1996. Genetics, Ecology, and Conservation of Montane Populations of Colorado Chipmunks. Journal of Mammalogy, 77: 951-975.

Whitaker Jr., J. 2002. "Colorado Chipmunk" (On-line ). Accessed 11/04/02 at http://www.enature.com/fieldguide/showSpeciesSH.asp?curGroupID=5&shapeID=1041&curPageNum=39&recnum=MA0198.