Tamias obscurus J.A.Allen 1890
Creators: name: Wilson, Don E.
name: Thomas E. Lacher, Jr
name: Mittermeier, Russell A.
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Rodentia
Sciuridae
Tamias
Tamias obscurus

description: 189. California Chipmunk <i>Tamias obscurus</i> <b>French:</b> Tamia du chaparral / <b>German:</b> Kalifornien-Backenhornchen / <b>Spanish:</b> Ardilla listada de California <b>Taxonomy.</b> Tamias obscurus J. A. Allen, 1890, “San Pedro [Martir] Mountains,” Baja California, Mexico. Three subspecies are recognized. <b>Subspecies and Distribution.</b> T.o.obscurusJ.A.Allen,1890—extremeSCalifornia(USA)andBajaCaliforniaStoSierradeSanPedroMartir(Mexico). T.o.davisiCallahan,1977—SanBernardinoandSanJacintoMts,SCalifornia(USA). T. o. meridionalis Nelson &amp; Goldman, 1909 — Sierra de San Francisco, Baja California Sur (Mexico). <b>Descriptive notes.</b> Head—body 124-1-128-3 mm,tail 103-3—-117 mm; weight mean 69 g. Dorsal pelage of the California Chipmunk has five dark chestnut stripes, very distinct in winter but drab and inconspicuous in spring. It can be differentiated from the sympatric Merriam’s Chipmunk (7. merriami) in California by its smaller size and grayer venter. Nominate obscurus has dorsal pelage that is gray suffused with brown, inconspicuous dorsal stripes, and shortertail. Subspecies davisi has a gray throat and upper chest. Subspecies meridionalis is smaller and grayer. Chromosome number of the California Chipmunk is 2n = 38. Two karyotypes are present within obscurus. Subspecies obscurus and meridionalis have karyotype A which consists of four pairs of metacentric autosomes,six pairs of submetacentric autosomes, eight pairs of acrocentric autosomes, a submetacentric X chromosome, and an acrocentric Y chromosome. Subspecies davisi has karyotype B which consists of five pairs of metacentric autosomes, six pairs of submetacentric autosomes, seven pairs of acrocentric autosomes, a submetacentric X chromosome, and an acrocentric Y chromosome. <b>Habitat.</b> Pinyon-juniper (Pinus, Pinaceae; Juniperus, Cupressaceae) and pine-oak (Pinus, Quercus, Fagaceae) vegetation, at elevations of ¢.1200-3000 m. Habitat use varies along geographical and elevational distributions. In California, it inhabits pine-fir-oak (Pinus, Abies, Pinaceae; Quercus) forests in the transition zone, pinyon-juniper (Pinus; Juniperus) vegetation in the upper Sonoran zone, lodgepole pine—chinquapin (FP. contorta, Chrysolepis sempervirens, Fagaceae) vegetation in the Canadian life zone, and oak chaparral (Quercus chrysolepis, Adenostoma, Rosaceae) in elevations below ¢.1500 m. In Mexico, it can be found on rock outcrops, talus slopes, and even in palm-cactus stands in the lower Sonoran life zone. <b>Food and Feeding.</b> Diet of the California Chipmunk consists of seeds, fruits, and flowers. Acorns, pinyon seeds, juniper, and manzanita berries are usually consumed, and oak seeds are frequently cached in a larderhoard. It may have limited or no access to free water in parts ofits distribution. <b>Breeding.</b> The California Chipmunk has a long breeding season, fromJanuary through June, though likely only produces one litter a year of 3-4 young. Elevation affects timing of breeding period, with mating of subspecies meridionalis occurring in early January, in Baja California, but in early March in Sierra Juarez at elevations of ¢.1500 m. <b>Activity patterns.</b> The California Chipmunk is terrestrial, diurnal, and active yearround. It may not leave its nest during entire winter season. Daily activity is bimodal, with the first peak at early morning and the second peak at late afternoon. Burrow structure is very variable, ranging from straight deep tunnels to systems with short side branches and nest chambers. One burrow was reported to have beads of condensed water on the ceiling, which could have provided some water to the inhabitant. Nests in fallen logs and cactus cavities are also reported. <b>Movements, Home range and Social organization.</b> There is no information available for this species. <b>Status and Conservation.</b> Classified as Least Concern on The IUCN Red List. Current population trend is stable; however, the distribution of the California Chipmunk is restricted and fragmented. The rarity of the California Chipmunk makes it valuable in the pet trade. The small, fragmented distribution makes it susceptible to local changes to landscapes, and its dependence on mountain forests could make it vulnerable to climate change. <b>Bibliography.</b> Best &amp; Granai (1994a), Linzey, Timm, Alvarez-Castafeda, Castro-Arellano &amp; Lacher (2008v), Thor ington et al. (2012).
description: Published as part of <i>Don E. Wilson, Thomas E. Lacher, Jr &amp; Russell A. Mittermeier, 2016, Sciuridae, pp. 648-837 in Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona :Lynx Edicions</i> on page 793, DOI: 10.5281/zenodo.6840226