Animal Diversity Web

Ge­o­graphic Range

Hopi chip­munks are found only in west­ern North Amer­ica from north-cen­tral Ari­zona to Mon­u­ment Val­ley as well as into east­ern Utah, east­ern Idaho, west­ern Col­orado (re­stricted to Yampa River south­ward), and into the Rocky Moun­tain Range to­wards Canada. (Burt and Best, 1994; Good, et al., 2003; Saldaña-DeLeon and Jones, 1998)

• Biogeographic Regions
• nearctic
  • native

Habi­tat

Hopi chip­munks pre­fer bare or veg­e­tated rocky sub­strate that con­tains ju­niper and pinyon pine. In west­ern Col­orado, they oc­cupy two mi­cro­hab­i­tats: sage patches and ju­niper/pine patches. Hopi chip­munks live at el­e­va­tions of 1,290 to 2,700 me­ters. (Burt and Best, 1994; Root, et al., 2001)

• Habitat Regions
• temperate
• terrestrial

• Terrestrial Biomes
• desert or dune
• mountains

• Range elevation

  1,290 to 2,700 m

  to ft

Phys­i­cal De­scrip­tion

Hopi chip­munks are small, mono­typic chip­munks in the sub­genus Neo­tamias. They weigh 47.9 to 59.3 grams de­pend­ing on the sea­son. Their ex­ter­nal length mea­sures 197 to 235 mm. Fe­males are gen­er­ally slightly larger than males but have no other dis­tinct dif­fer­ences in mor­phol­ogy. The col­or­ing is buffy and gray patch­work. Up­per­parts have black stripes high­lighted with tones of or­ange-red run­ning in an an­te­rior to pos­te­rior di­rec­tion down its back. Hopi chip­munks also have pale fa­cial white and "ru­fous" fa­cial stripes with the lower stripe ex­tend­ing under the ears. The tail is mixed black and chest­nut dor­sally and chest­nut with faint black stripes ven­trally. There are two an­nual molts: one in the spring and one in early au­tumn. The den­tal for­mula is I 1/1, C 0/0, P 2/1, M 3/3, to­tal­ing 22 teeth. The skull has a long and nar­row brain­case, short nasals, a nar­row in­teror­bital re­gion, and rather large au­di­tory bul­lae. (Burt and Best, 1994; Hall, 1981; Hoffmeis­ter and Ellis, 1979; Lev­en­son, et al., 1985; Nowak, 1999; Saldaña-DeLeon and Jones, 1998; Wil­son and Reeder, 2005)

• Other Physical Features
• endothermic
• bilateral symmetry

• Sexual Dimorphism
• female larger

• Range mass

  47.9 to 59.3 g

  1.69 to 2.09 oz

• Range length

  197 to 235 mm

  7.76 to 9.25 in

Re­pro­duc­tion

The mat­ing be­hav­ior of Hopi chip­munks is un­known. In other Neo­tamias species such as Mer­riam's chip­munks (Tamias mer­ri­ami), sev­eral males con­gre­gate in areas where there are many fe­males. Males run around if an es­trous fe­male is nearby. It is un­known if males chase the fe­male until one cor­ners her for cop­u­la­tion (such as in the East­ern chip­munk) or if males per­form a dis­play. When a male ap­proaches a fe­male, he rubs his body and face against hers. This may be a form of scent-mark­ing, and pre­cedes cop­u­la­tion. Pre-cop­u­la­tion vo­cals and mat­ing calls have been noted in other Neo­tamias chip­munks and are most likely uti­lized by Hopi chip­munks. (Comp­ton and Calla­han, 1995; Nowak, 1999; Yah­ner, 1978)

• Mating System
• polygynous

The breed­ing sea­son of Hopi chim­punks is from Feb­ru­ary until mid-April. Males pre­pare for the breed­ing sea­son by be­com­ing sex­u­ally ac­tive through en­large­ment of testes about a week after emerg­ing from their win­ter dens. Fe­males are pre­pared for mat­ing im­me­di­ately after ex­it­ing their win­ter dens. Fe­males give birth to one lit­ter after a ges­ta­tion pe­riod of 30 to 33 days. Young chip­munks weigh an av­er­age of 3 grams at birth. The heads of the young are larger than bod­ies and they have no hair. The young are cold to the touch until they are a week old. They have a fairly uni­form growth rate and gain 0.50 g per day on av­er­age. By 2 weeks, the color of the adult fa­cial pat­terns be­comes vis­i­ble, the in­cisors have erupted, the toes have begun to sep­a­rate, and the young can drag them­selves using their front legs. By 3 weeks, the hair be­comes smooth and more adult-like, the toes are fully sep­a­rated, and the young can move more ef­fi­ciently. At 5 weeks, the young be­come ac­tive out­side and the cheek-teeth have erupted. At 6 weeks, they are con­sum­ing solid foods. Wean­ing is a slow process and usu­ally oc­curs when the young are 6 to 7 weeks old and by then are fully in­de­pen­dent. Sex­ual ma­tu­rity usu­ally oc­curs at 10 to 12 months with most fe­males hav­ing their first lit­ter in their first year. (Burt and Best, 1994; Hoffmeis­ter and Ellis, 1979; Nowak, 1999; Root, et al., 2001)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• fertilization

• Breeding interval

  Hopi chipmunks breed once a year between February and April.

• Breeding season

  Breeding season of Hopi chipmunks runs from February to April.

• Range number of offspring

  4 to 7

• Average number of offspring

  5

• Range gestation period

  30 to 33 days

• Average gestation period

  31 days

• Range weaning age

  6 to 7 weeks

• Average weaning age

  6 weeks

• Range time to independence

  6 to 7 weeks

• Average time to independence

  6 weeks

• Range age at sexual or reproductive maturity (female)

  10 to 12 months

• Average age at sexual or reproductive maturity (female)

  10 months

• Range age at sexual or reproductive maturity (male)

  10 to 12 months

• Average age at sexual or reproductive maturity (male)

  10 months

The mother cares for the young ex­ten­sively until they are ca­pa­ble of being in­de­pen­dent. Wean­ing is a grad­ual process. Males con­tribute no parental care to­wards the young. (Burt and Best, 1994)

• Parental Investment
• altricial
• female parental care
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female
• pre-independence
  • provisioning
    • female
  • protecting
    • female

Lifes­pan/Longevity

Exact lifes­pan of Hopi chimp­munks is un­known. The max­i­mum lifes­pan of other Tamias chip­munks in cap­tiv­ity is roughly 9.5 years, but their lifestyle tends to lower their life ex­pectancy con­sid­er­ably. The longest ex­pected lifes­pan in the wild is 8 years, but most in­di­vid­u­als sur­vive only 2 to 3 years, and only 10% of in­di­vid­u­als sur­vive their first 64 months of life. (Bergstrom and Hoff­mann, 1991; Gor­bunova, et al., 2008; Nowak, 1999)

• Range lifespan
  Status: wild

  8 (high) years

• Range lifespan
  Status: captivity

  5 to 9.5 years

• Typical lifespan
  Status: wild

  2 to 8 years

• Average lifespan
  Status: wild

  2-3 years

Be­hav­ior

Hopi chip­munks are di­ur­nal and ac­tive dur­ing the early morn­ing hours, es­pe­cially fol­low­ing rain­storms or thun­der­show­ers. They are also hi­ber­na­tors, usu­ally de­creas­ing ac­tiv­ity just be­fore the breed­ing sea­son from No­vem­ber to April. Hopi chip­munks do not hi­ber­nate for great lengths of time, es­pe­cially since the species can be ac­tive until late No­vem­ber and pe­ri­od­i­cally leave their dens dur­ing the win­ter. Hopi chip­munks often in­ter­act with other species of chip­munks in west­ern North Amer­ica, cre­at­ing a very dis­tinct eco­log­i­cal com­mu­nity that is based on their en­vi­ron­men­tal pref­er­ence. This cre­ates a mo­saic of dif­fer­ent mi­cro­hab­i­tats in which the Hopi chip­munks oc­cupy higher el­e­va­tions while species such as yel­low-pine chip­munks (Tamias amoenus) oc­cupy the lower re­gions. This sug­gests that Hopi chip­munk in­ter­ac­tions with other Tamias species are lim­ited by habi­tat pref­er­ence and ge­o­log­i­cal iso­la­tion and do not in­clude hy­bridiza­tion be­tween species. Knowl­edge of in­ter­ac­tions be­tween species is lim­ited, but com­par­ing with other Tamias species, it can be as­sumed that Hopi chip­munks share sim­i­lar char­ac­ter­is­tics of soli­tary liv­ing and tend to dis­play dom­i­nance and soli­tary be­hav­ior when other chip­munks enter their ter­ri­tory. (Burt and Best, 1994; Good, et al., 2003; Nowak, 1999; Yah­ner, 1978)

• Key Behaviors
• scansorial
• terricolous
• diurnal
• motile
• sedentary
• hibernation
• solitary
• territorial

• Range territory size

  0.005 to 0.0128 km^2

Home Range

Home range is hard to cal­cu­late in a two-di­men­sional space be­cause Hopi chip­munks are avid climbers whose home range may in­clude trees and sand­stone cliffs. Pro­jected ter­ri­tory size varies among males, fe­males, and ju­ve­niles. Ter­ri­tory size is 1.28 ha for adult males and 1.04 ha for adult fe­males. Ter­ri­tory size of ju­ve­niles is no larger than 0.50 ha. (Burt and Best, 1994)

Com­mu­ni­ca­tion and Per­cep­tion

Com­mu­ni­ca­tion and per­cep­tion strate­gies of Hopi chip­munks are likely sim­i­lar to other Neo­tamias species. These an­i­mals pro­duce two main cat­e­gories of calls: alarm calls and ag­o­nis­tic (courtship) sounds. Alarms calls vary and may in­clude a chip, chuck, or "chip­per­ing" sound. Trills and whis­tles have also been recorded. Courtship sounds were sim­i­lar, but tended to be much harsher. (Nowak, 1999)

• Communication Channels
• visual
• tactile
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

The diet of Hopi chip­munks con­sists largely of the berries and seeds of its local re­gion. The va­ri­ety and type avail­able for con­sump­tion is af­fected by the sea­son and ge­o­graph­i­cal range. In Utah, Hopi chip­munks feed pri­mar­ily on the berries of the one-seeded ju­niper (Ju­nipe­rus monosperma). In other areas, in­di­vid­u­als feed on cliff rose, squaw­berry (Rhus trilo­bata), moun­tain ma­hogany, and seeds and nuts from Russ­ian this­tle, pinyon pine, and the Gam­bel and waxy leaf oaks. In late spring and sum­mer, Hopi chip­munks feed on green veg­e­ta­tion. In the fall, their diet changes to favor nuts as they be­come avail­able. The species also has been seen caching food in rocky ledges and uti­lizes its large cheek pouches to carry food to caches. Hopi chip­munks do not typ­i­cally eat leaves or stems in the wild al­though in cap­tiv­ity, they are known to eat parts of dan­de­lions. They need con­stant ac­cess to water, and can die of thirst if de­prived of water for only 2 days. (Burt and Best, 1994; Nowak, 1999)

• Primary Diet
• herbivore
  • folivore
  • granivore
  • lignivore

• Plant Foods
• leaves
• roots and tubers
• wood, bark, or stems
• seeds, grains, and nuts
• flowers

• Foraging Behavior
• stores or caches food

Pre­da­tion

Hopi chip­munks are eaten by snakes, birds, and pos­si­bly mam­mals. Bull­snakes (Pituophis catenifer sayi) have been known to eat ju­ve­nile chip­munks. Other preda­tors in­clude coy­otes (Canis la­trans), Swain­son's hawks (Buteo swain­soni), and long-tailed weasels (Mustela fre­nata). The exact mor­tal­ity of the chip­munks by these preda­tors is not known. (Burt and Best, 1994)

• Known Predators

  • bullsnakes (Pituophis catenifer sayi)
  • coyotes (Canis latrans)
  • Swainson's hawks (Buteo swainsoni)
  • long-tailed weasels (Mustela frenata)

Ecosys­tem Roles

Mites and fleas are com­mon par­a­sites that in­fect Hopi chip­munks. In one case, bot­fly larva (likely Cutere­bra) was found under the skin of an in­di­vid­ual, but it is not known whether this lar­vae typ­i­cally uses the Hopi chip­munk as a host. Hopi chip­munks dis­plays caching be­hav­ior, so it can be as­sumed that it may also dis­perse seeds. The species also in­ter­acts with a large num­ber of west­ern chip­munks in North Amer­ica, but due to its habi­tat pref­er­ence, it is thought that there are not a lot of in­ter­spe­cific in­ter­ac­tions in the ecosys­tem. (Burt and Best, 1994; Nowak, 1999)

• Ecosystem Impact
• disperses seeds

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

The pos­i­tive im­pact of the Hopi chip­munk on hu­mans is un­known, but most likely min­i­mal. Some chip­munks of the sub­genus Neo­tamias are killed for their skins in the fur trade, al­though it is not cer­tain if Hopi chip­munks are in­cluded in this trade. (Nowak, 1999)

• Positive Impacts
• body parts are source of valuable material

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There have been sug­ges­tions that Hopi chip­munks dam­age crops (as some Neo­tamias live close to agri­cul­tural areas) but the species rarely oc­curs in large enough con­cen­tra­tions to cause much dam­age. (Nowak, 1999)

• Negative Impacts
• crop pest

Con­ser­va­tion Sta­tus

Hopi chip­munks are con­sid­ered sta­ble and not en­dan­gered. There has been some con­cern that habi­tat loss due to agri­cul­tural and urban ex­pan­sion may ad­versely af­fect Neo­tamias species in the fu­ture. (Nowak, 1999; Wil­son and Reeder, 2005)

• IUCN Red List

  Least Concern

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Other Com­ments

The species has been called by dif­fer­ent names, which in­clude the 1905 clas­si­fi­ca­tion of Eu­tamias hopi­en­sis. The species has also been called Eu­tamias quadrivit­ta­tus rufus, sug­gest­ing it to be a sub­species of Col­orado chip­munks (Eu­tamias quadrivit­ta­tus), but there has been con­sid­er­able de­bate con­cern­ing the arrange­ment of Neo­tamias and Eu­tamias and where Tamias falls under as a sub­genus. Stud­ies such as the size of the skull and bac­u­lum, as well as body shape and col­or­ing, have sought to see if T. quadrivit­ta­tus and T. rufus are sub­species or sep­a­rate species. As of now, Hopi chip­munks are clas­si­fied as Tamias rufus, sep­a­rate from Eu­tamias quadrivit­ta­tus. (Hoffmeis­ter and Ellis, 1979; Nowak, 1999; Pat­ter­son, 1984; Wil­son and Reeder, 2005)

Con­trib­u­tors

Jes­sica Mor­ris (au­thor), Uni­ver­sity of Alaska Fair­banks, Laura Prugh (ed­i­tor), Uni­ver­sity of Wash­ing­ton.

Ref­er­ences

Bergstrom, B., R. Hoff­mann. 1991. Dis­tri­b­u­tion and Di­ag­no­sis of Three Species of Chip­munks (Tamias) in the Front Range of Col­orado. The South­west­ern Nat­u­ral­ist, 36: 14-28.

Burt, S., T. Best. 1994. Mam­malian Species: Tamias Rufus. The Amer­i­can So­ci­ety of Mam­mal­o­gists, 460: 1-6.

Comp­ton, S., J. Calla­han. 1995. RE­PRO­DUC­TIVE BE­HAV­IOR IN MER­RIAM'S CHIP­MUNK ( TAMIAS MER­RI­AMI ). Great Basin Nat­u­ral­ist, 55: 89-91.

Good, J., J. Dem­boski, D. Nagorsen, J. Sul­li­van. 2003. PHY­LO­GEOG­RA­PHY AND IN­TRO­GRES­SIVE HY­BRIDIZA­TION: CHIP­MUNKS (GENUS TAMIAS) IN THE NORTH­ERN ROCKY MOUN­TAINS. Evo­lu­tion, 57: 1900-1916.

Gor­bunova, V., M. Bozzella, A. Selu­anov. 2008. Ro­dents for com­par­a­tive aging stud­ies: from mice to beavers. AGE, 30: 111-119.

Hall, E. 1981. Mam­mals of North Amer­ica Vol­ume 1. New York: John Wiley & Sons.

Hoffmeis­ter, D., L. Ellis. 1979. Ge­o­graphic Vari­a­tion in Eu­tamias quadrivit­ta­tus with Com­ments on the Tax­on­omy of Other Ari­zo­nan Chip­munks. The South­west­ern Nat­u­ral­ist, 24: 655-665.

Lev­en­son, H., R. Hoff­man, C. Nadler, L. Deutsch, S. Free­man. 1985. SYS­TEM­AT­ICS OF THE HO­L­ARC­TIC CHIP­MUNKS (TAMIAS). Jour­nal of Mam­mal­ogy, 66: 219-242.

Nowak, R. 1999. Walker's Mam­mals of the World 6th Edi­tion Vol­ume II. Bal­ti­more and Lon­don: The John Hop­kins Uni­ver­sity Press.

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

Root, J., C. Cal­isher, B. Beaty. 2001. MI­CRO­HAB­I­TAT PAR­TI­TION­ING BY TWO CHIP­MUNK SPECIES (TAMIAS) IN WEST­ERN COL­ORADO. West­ern North Amer­i­can Nat­u­ral­ist, 61: 114-118.

Saldaña-DeLeon, J., C. Jones. 1998. An­no­tated check­list of the re­cent mam­mals of Col­orado. Mu­seum of Texas Tech Uni­ver­sity: 1-16.

Wil­son, D., D. Reeder. 2005. Mam­mal Species of the World Vol­ume II. Bal­ti­more and Lon­don: The John Hop­kins Uni­ver­sity Press.

Yah­ner, R. 1978. The Adap­tive Na­ture of the So­cial Sys­tem and Be­hav­ior in the East­ern Chip­munk, Tamias stria­tus. Be­hav­ioral and So­cio­bi­ol­ogy, 3: 397-427.