Yellow-pine chipmunks have 10 different recognizable vocalizations. Most of these calls are alarm calls to alert conspecifics of predators. When greeting conspecifics, they first touch noses, then smell the sides of the face and neck, and last they sniff the anus. Visual signals, such as body posture, are important in communication.
Communication Channels: visual ; tactile ; acoustic ; chemical
Perception Channels: visual ; tactile ; acoustic ; chemical
Yellow-pine chipmunks are common in the northwestern United States and southwestern Canada. The species has no special status.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Yellow-pine chipmunks have been identified as hosts for the disease vectors responsible for Colorado tick fever, tick-borne relapsing fever, hantavirus pulmonary syndrome, and Rocky Mountain spotted fever richettsia. They also become heavily infested with bot fly warbles and fleas that are known to carry plague.
Destruction by yellow-pine chipmunks of young conifers intended for timber harvest has been documented, however the overall damange is insubstantial.
Negative Impacts: injures humans (causes disease in humans , carries human disease); causes or carries domestic animal disease
Like most chipmunks, yellow-pine chipmunks are favored among nature lovers. This species is less destructive of young conifers (often harvested by humans for timber) than other small mammals.
Positive Impacts: research and education
Yellow-pine chipmunks are important dispersers of the seeds of various conifer species. They also contribute to the food base of many different carnivore species.
Ecosystem Impact: disperses seeds
Species Used as Host:
Mutualist Species:
Commensal/Parasitic Species:
Yellow-pine chipmunks are mostly omnivorous. They consume at least 59 species of seeds, plants, fruits, fungi, corms, and insects. They are also known to eat small mammals, bird eggs, and roots. They use their cheek pouches to carry conifer seeds and other foods to their burrows.
These chipmunks forage both on the ground and in trees. Foraging is done during the day and from spring to fall. In the fall, they begin storing food in caches for winter. Winter caches of up to 68,000 items, ranging from seeds to bumble bees, have been recorded.
Animal Foods: mammals; eggs; insects; terrestrial non-insect arthropods; terrestrial worms
Plant Foods: leaves; roots and tubers; seeds, grains, and nuts; fruit; flowers
Other Foods: fungus
Foraging Behavior: stores or caches food
Primary Diet: omnivore
Yellow-pine chipmunks, Tamias amoenus, are found in the northwestern United States and southwestern Canada. They occur throughout Idaho, Washington, and Oregon (excluding coastal areas), as well as northern Nevada and northern Utah, western Wyoming and western Montana, and mountainous areas of California. In Canada, yellow-pine chipmunks occupy most of southern British Colombia and the mountainous regions of southwestern Alberta.
Biogeographic Regions: nearctic (Native )
Yellow-pine chipmunks are most common in brushy coniferous forests, but can be found in a broad range of habitat types including areas with rocky outcrops, chaparral, and meadows. They occupy areas that are dominated by shrubs such as service berry (Amelanchier), snowberry (Symphoricarpos), mountain mahogany (Cercocarpus), currant (Ribes), antelope brush (Purshia), and buckbrush (Ceanothus).
Yellow-pine chipmunks require logs, snags, rock crevices, or stumps for nesting, in addition to shrubs and ground litter for cover.
Yellow-pine chipmunks typically occur at altitudes ranging from 600 to 2,800 m, however in Washington they have been recorded at elevations of up to 4,300 m.
Range elevation: 600 to 4,300 m.
Average elevation: 2,800 m.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: chaparral ; forest ; mountains
Other Habitat Features: riparian
Yellow-pine chipmunks have been known to live up to 5 years 2 months in the wild. Young have a 30% survival rate. Once they emerge from the den at about 6 weeks of age, they are easy prey for a variety of predators. Adults have a summer survival rate of 33% to 88% and a winter survival rate of 97%.
No information was available on the lifespan and survival rate of captive yellow-pine chipmunks.
Average lifespan
Status: wild: 5 years.
Average lifespan
Status: wild: 3 years.
Yellow-pine chipmunks are small compared to other members of the genus Tamias. They measure 181 to 245 mm in length, and can weigh between 30 and 70 g. Females tend to be larger than males.
These animals have five black, evenly-spaced, longitudinal stripes down the back. The three dorsal stripes extend from shoulder to rump, whereas the two lateral strips extend only to mid-body. The pale stripes are usually white or grayish. Body color varies depending upon subspecies. Tamias amoenus affinis has a pinkish-cinnamon colored body, T. a. monoensis is a cinnamon buff, T. a. luteiventris is sayal-brown, T. a. felix is ochraceous tawny, and T. a. ludibundus is tawny. The underside of the tail ranges from pinkish-cinnamon to grayish-yellow to sayal-brown. The ears are whitish behind and black in front.
Yellow-pine chipmunks can be distinguished from similar species by the genital bones of both sexes. They can also be distinguished based upon size and color. Lodgepole chipmunks are larger than yellow-pine chipmunks, have bigger ears, and more sharply contrasting stripes. The outer stripes of lodgepole chipmunks are also wider than the inner stripes. Least chipmunks are smaller than yellow-pine chipmunks, and also paler in color. Yellow-pine chipmunks are smaller and redder than Unita chipmunks. Unita chipmunks also have grayer shoulders and heads.
Range mass: 30 to 73 g.
Range length: 181 to 245 mm.
Sexual Dimorphism: female larger
Other Physical Features: endothermic ; bilateral symmetry
Average basal metabolic rate: 0.5 W.
Yellow-pine chipmunks usually live in underground burrows, which help conceal them from predators. The black and white stripes on the back of these animals help to camouflage them in open forests where sharp shadows are cast by the sun. They also have, to some extent, a system of watch where one chipmunk looks out for predators and warns the others with alarm vocalizations. This is mostly observed in more open areas where chipmunks are more exposed to predators.
Predators include coyotes (Canis latrans), goshawks (Accipiter gentilis), long-tailed weasels (Mustela frenata), badgers (Taxidea taxus), bobcats (Lynx rufus), rattlesnakes (Crotalus viridis), and sparrow hawks (Falco sparverius).
Known Predators:
Anti-predator Adaptations: cryptic
Yellow-pine chipmunks are polygynandrous. Females are in estrous for one day each year. They use vocalizations to attract mates a few days before the onset of estrous. On the day of estrous, females are typically pursued by two to six males in what is called a “mating chase”. A female mates with multiple males during this mating chase. All sexually mature males and females mate during the mating season, which occurs in late April or early May.
Mating System: polygynandrous (promiscuous)
Female yellow-pine chipmunks are in estrous for one day and breed only once per year during late April to early May. Average gestation period is 30 days, after which a female usually gives birth to a litter of 3 to 8 babies. Young are highly altricial at birth and remain in the burrow until they are weaned at six weeks of age. Young begin to disperse and find their own burrows at about 8 to 12 weeks of age. They reach sexual maturity at 12 to 23 months.
Breeding interval: Yellow-pine chipmunks breed only once per year.
Breeding season: Breeding occurs in late April or early May.
Range number of offspring: 3 to 8.
Average number of offspring: 4 to 5.
Range gestation period: 28 to 40 days.
Average gestation period: 30 days.
Average weaning age: 45 days.
Range time to independence: 2 to 3 months.
Range age at sexual or reproductive maturity (female): 12 to 23 months.
Range age at sexual or reproductive maturity (male): 12 to 23 months.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Average birth mass: 2.62 g.
Average number of offspring: 5.19.
Pregnant females make nests of leaves, grass, lichen, and feathers in burrows that are about 1.5 m below ground or up to 18 m in trees. Babies are altricial and depend on the mother for food and protection until they emerge from the burrow at about 6 weeks of age. Males do not contribute to the care of the offspring. At about 8 weeks of age, young of both sexes disperse to find their own nests and burrows for winter.
Parental Investment: altricial ; 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)
The yellow-pine chipmunk (Neotamias amoenus) is a species of order Rodentia in the family Sciuridae. It is found in western North America: parts of Canada and the United States.[2]
These chipmunks are normally found in brush-covered areas, and in California, they inhabit an elevation range of around 975 to 2,900 meters.[2]
Their body color is dark and reddish, mixed with cinnamon, with five longitudinal dark (black or mixed black) stripes that are separated by four lighter stripes. The outer pair of pale stripes is creamy white and narrower, and the more median pair is a gray or smoke gray. The sides of the head each have three dark stripes, with two lighter in between, and the crown is black or smoke gray.[2]
Males and females have similar brain size and roughly the same tail length, ear length from notch, and length of lower tooth row, but females are larger in other body measurements; average body mass varies, with large males weighing an average of 49.7 g and large females averaging 53.5 g.[2] Though male-biased size sexual dimorphism is common among mammals, N. amoenus exhibits female-biased dimorphism.[3]
In some areas, where range overlap with the least chipmunk or red-tailed chipmunk occurs, it may be difficult or impossible to distinguish the species in the field; laboratory examination of skeletal structures may be required[4][5]
Yellow-pine chipmunks are seed-storing hibernators whose fitness in winter and spring seasons is influenced by the availability of resources and their foraging behaviors in the summer and autumn.[6] Since they do not build body fat before hibernation, their larder, or winter food supply they have built, serves as a measure for their likelihood of survival through the winter, and of their reproductive success come spring.[6] During the warm, active season, the chipmunks gather accessible seeds and scatter-hoard the seeds in various caches, only to retrieve them later for their larder.[6] N. amoenus avoids cache overlap with its loads, and mean nearest-neighbor distance ranges from 1.4–4.9 m; these distances between caches increases the farther N. amoenus gets from its food source.[7]
Both sexes have genital bones; males possess a baculum and females a baubellum.[2] After hibernation, one annual breeding event takes place in late April/early May; male testes sizes are enlarged at this time (bolstered by the warmer temperatures); similarly, enlargement of female ovaries and uteri is also seen.[2] The females are in estrus for one day, and 3 to 5 days prior they make vocalizations, making males aware of their readiness to reproduce and eliciting intrasexual selection among males.[3] The female mates with one or more of the males that has come to her den.[3] The average litter number is around four or five and birth occurs late May/early June; in a litter of six, young are smaller, suggesting physical constraints on the mother; the lactation period lasts about 2 months, and by beginning of September, the young are of comparable size to others in the population.[2] Female reproductive success has been observed to be significantly related to body size, whereas male reproductive success is independent of size.[3]
The yellow-pine chipmunk (Neotamias amoenus) is a species of order Rodentia in the family Sciuridae. It is found in western North America: parts of Canada and the United States.
These chipmunks are normally found in brush-covered areas, and in California, they inhabit an elevation range of around 975 to 2,900 meters.
