Lodgepole Chipmunk Tamias Speciosus AKA San Bernardino Chipmunk

The Lodgepole Chipmunk (Tamias speciosus) is a species of rodent in the family Sciuridae which is found at relatively high elevations in San Bernardino County’s mountains.
Tamias speciosus has a range that is almost but not quite exclusive to California, spilling over as it does into a small portion of Nevada. It is found at elevations from 4,900 to 9,800 feet in the high Sierra Nevada, San Jacinto, San Bernardino, and San Gabriel Mountain ranges of California into the Lake Tahoe region of the west central corner of Nevada.
The Lodgepole Chipmunk has a variety of common names including the Tahoe Chipmunk, Sequoia Chipmunk, Mt. Pinos Chipmunk, and San Bernardino Chipmunk. It lives in subalpine coniferous forests made primarily of Lodgepole, Jeffrey, Ponderosa, and Sugar pines and Douglas, white and red firs. They can be observed foraging around and on top of rocks and fallen logs, which make up the forest floor.
In 1978, botanist Mark A. Chappell noted the Lodgepole Chipmunk proliferated from 7,872 feet to 9,840 feet in the lodgepole pine zone, between the alpine zone (9,840+ feet) and the Piñon pine/mountain mahogany zone (6,32 feet to 7,872 feet). Other types of chipmunks preferred habitats that are generally lower. This ecological competition for different zones of a single area is determined by physiological and environmental limits, where each species is limited specifically to a zone that best fits that particular species’ physiological traits. Fires that burned and thinned the forest did not seem to have a significant impact on the species in respect to population number. Observations did indicate that body mass of chipmunks living in burned or thinned areas decreased because forest structure changed, limiting food availability provided by the cones of trees.
Natural predators of the Lodgepole Chipmunk include coyotes, foxes (primarily the gray fox), hawks (Cooper’s and Red-Tailed), bobcats, and martens. To avoid such threats, the Lodgepole Chipmunk is capable of climbing trees in order to seek safety and also minimize open exposure by utilizing the color patterns and markings of its fur to blend in to its surroundings, providing camouflage against the environment.
Several different vocalizations are used by the Lodgepole Chipmunk during both courtship and when frightened by a predator. During courtship, visual displays can be shown through the action of tail flipping and body postures of both genders. Alongside visual displays, during courtship males and females utilize chips and whistles. When frightened or alerting others, the Lodgepole Chipmunk produces a high pitched “whisk,” a shrill “tsew,” as well as the series “pst-pst-pst-a-ku” in a rapid and repeated manner.
After caching food throughout the spring and summer months, hibernation begins at the end of October and lasts until early to mid April, a five to six month span
The Lodgepole Chipmunk is an omnivore, feeding on a multiple of both animal (mammals, birds, bird eggs, small invertebrates arthropods, and insects) and plant matter (leaves, flowers, pollen, forbs, fungi, and seeds). Like most rodents, this chipmunk engages in the foraging behavior of caching and storing food in order to survive the long winter hibernation. The Lodgepole Chipmunk is also known to serve two main ecological roles. Through its diet, this chipmunk ingests seeds, which are not broken down through the digestive process, and the seeds are then defecated and dispersed throughout its habitat, spreading variation and enhancing the range of the seed-producing plant. Similarly, the Lodgepole Chipmunk also disperses ectomycorrhizal fungi. This kind of fungi is important to forests, allowing for trees to subsist by increasing their water and nutrient gains. By dispersing spores, seeds, and pollen, the Lodgepole Chipmunk plays an important role in the maintenance of the forest and mountain ecosystem.
Through visual displays and vocalizations, both males and females engage in courtship. When the scrotum turns black and the testes are loosely relaxed, the male is ready to mate. Once per year Lodgepole Chipmunks breed during May to early June. Three to six young (pups) are born in early June after a one-month gestation period. Lactation provided by the mother allows nourishment to poorly developed pups, lasting for approximately one month, and then the young are independent by fall. Young reach sexual maturity the following spring. Though not known, it is expected that like other relatives, the Lodgepole Chipmunk exhibits a polygynous system of mating. Also, parental investment rests solely on the mother as the father of the litter does not provide parental care to his offspring.
Lodgepole chimpunks exhibit sexual dimorphism, as females, with an average body weight of 55-69 grams, are larger in size than males, with an average of 50-60 grams in total weight. Observed females have a body length ranging from 7 3/4 to 9 inches, while males typically exhibit an average body length of 7.8 to 8.7 inches. Body patterns remain consistent in both genders as they exhibit characteristic white dorsal and facial stripes, less prominent yellow-white central dorsal stripes than the lateral white stripes and darker and more broad facial stripes than other chipmunks. Other notable body patterns include dark black dorsal stripes, a lack of a black stripe underneath the prominent white lateral stripe, bright orange color on sides and orange-gray coloring on the shoulders, a gray under-belly, and a gray rump. The top of the head, the crown, is known to be brown with some gray interspersed. The tail, lengthier in females, ranges from 0.5 to 0.87 inches and is characterized by its black tip and cinnamon body.

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