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The red-tailed chipmunk inhabits dense coniferous forests. Its numbers are greatest where shrubby growth is rich. These conditions typically occur in forest openings or edges. They can be found in forests of -Tsuga heterophylla- (western hemlock), -Thuja plicata- (western red cedar), -Pseudotsuga menziesii- (Douglas fir), and -Picea englemanni- (Englemann spruce). They are limited by open -Pinus ponderosa- (Ponderosa pine) on the western edge of their range. -T. ruficaudus- occupies bunches of stunted pine and spruce trees, and -Rhododendron- (mountain rhododendron) and -Vaccinium- (blueberry bushes) on the margins of meadows. They occur in Washington in mixed second-growth forests of -Pinus contorta- (lodgepole pine), -Larix occidentalis- (western larch), Englemann spruce, Douglas fir, -Abies grandis- (grand fir), and -Populus tremuloides- (aspen).
In northern Idaho, the red-tailed chipmunk is considered to be the most widely distributed and common chipmunk. They are plentiful higher in the mountains. In the Ponderosa pine zone, they can be found in openings with great amounts of light where boulders and low brush are present. This usually occurs along older roadways and at the lower edge of foothills. -T. ruficaudus- can be found near fallen logs and brush piles in the Canadian zone.
This species of chipmunk typically resides in burrows and on the ground, but can climb trees and bushes at times. They look for protection in old logs, crevices among rocks, and their burrows. (Best, 1993; Nowak, 1999)
Terrestrial Biomes: forest
The red-tailed chipmunk is darker colored and larger than most chipmunks. The appearance of this chipmunk is generally similar to that of Tamias minimus (least chipmunk) and the yellow pine chipmunk. However, the red-tailed is larger and colored more brightly. In general, the pelage is rufous on the shoulders and sides, with this color fading out towards the hips. The back has a deep orange-brown tone and the rump is a shade of gray. The feet are a light brown color and the underparts are ivory. The color of the tail is rufous on the dorsal side with the ventral side a bright orange or brick red. The tail also has a black band and the tips of the hairs are yellowish. The ears are black. T. ruficaudus has five dark stripes that range from black to fuscous. The central dark stripe runs between the ears to the tail. The four pale stripes are grayish to white. The forehead is chocolate brown and the cheeks are characterized by two milky stripes separated by three brown stripes. The eye stripe is black and the stripe below the eye is brownish.
The winter pelage of T.ruficaudus is soft, dense and slightly wooly. There are two molts each year, one occurring in the spring and a second molt in the early autumn. The summer pelage differs from the winter in that it is more brightly colored.
The dental formula of the red-tailed chipmunk is 1/1 0/0 2/1 3/3=22. The skull has a short rostrum and is ovate. The postorbital processes are slender and long. The subgenus Neotamias, to which the red-tailed chipmunk belongs, is differentiated from the subgenus Tamias in that Neotamias has two premolars on each side of the upper jaw and Tamias only has one.
The red-tailed chipmunk is sexually dimorphic. Females are approximately 3% larger than males in head length and body. Males also have narrower skulls than females.
(Banfield, 1974; Best, 1993; Nowak, 1999; Smith, 1993)
Average mass: 60 g.
Other Physical Features: endothermic ; bilateral symmetry
Average mass: 75 g.
Average lifespan
Status: wild: 8.0 years.
The red-tailed chipmunk is found in the central Rocky Mountain region of the United States in northwestern Montana, northern Idaho and northeastern Washington. In Canada, the range of -Tamias ruficaudus- just touches extreme southwestern Alberta and the East Kootenay valley of southern British Columbia. (Banfield, 1974; Nowak, 1999)
Biogeographic Regions: nearctic (Native )
Red-tailed chipmunks gather dry food that they carry in their cheek pouches and store underground. They feed at discrete times during daylight hours. These animals become torpid in the winter and feed from time to time upon their larder. Their diet includes the seeds of fir trees, honeysuckles, locusts, and cranberries. In Idaho, they have also been observed feeding upon the seeds of Douglas knotweed. In Montana, the chipmunk eats the fruits and seeds of nine-bark, wild rose, Ponderosa pine, snow brush, serviceberry, big whortleberry, buckbrush, knotweed, grass, huckleberry, mountain maple, and bull thistle. They also eat the leaves and flowers of the dandelion, arnica, currant, balsam-root, glacier lilly, oyster plant, willow herb, and tarweed. -T. ruficaudus- has been caught in the wild with steel traps baited with meat. (Best, 1993; Nowak, 1999)
The red-tailed chipmunk can be tamed quite easily for the purposes of laboratory study. (Best, 1993)
Red-tailed chipmunks typically favor brush-covered or rugged land. However, sometimes they occur near agricultural crops. When this happens, they can do damage by eating planted seed, young forest plantings, and even fruit trees. (Nowak, 1999)
Generally, -Tamias ruficaudus- are abundant in most areas. They seem to have avoided the fate of some of their close relatives, -Tamias palmeri-, -Tamias minimus atristriatus-, and -Tamias quadrivittatus australis-, which have all appeared on the IUCN list or have become extinct. (Nowak, 1999)
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Perception Channels: tactile ; chemical
Two subspecies of Tamias ruficaudus are recognized, T. r. ruficaudus and T. r. simulans. These subspecies are differentiated based on their cranial and bacular morphology. Nevertheless, evidence of interbreeding among these taxa has been discovered, and there appears to be substantial gene flow throughout the species.
The name Tamias comes from the Greek tamias meaning storer or distributor. Ruficaudus is from the Latin rufus meaning reddish, and cauda meaning tail. Other names include rufous-tailed and Coeur d'Alene chipmunk. (Best, 1993; MSW Scientific Names)
Mating in -T. ruficaudus- can occur from late February to early July but usually takes place in April or May. Pregnancy rates vary among age groups. Females that were 10 to 16 months of age were pregnant less often than older females. The overall rate of pregnancy for the population was 68 to 83% where females 10 to 16 months of age were not considered. There is only one breeding season per year, unless a litter is lost. In this case the female can enter estrus again and bear a second litter. The gestation period is 28 to 36 days. Embryos of 25 mm in head-rump length are full term. The litter size is usually three to eight young and sexual maturity is reached within the first year of life. The record of longevity in the wild for chipmunks was achieved by -T.ruficaudus-. This particular animal lived for eight years. However, fewer than 10% of the individuals survive more than 64 months. (Best, 1993; Nowak, 1999)
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
Average gestation period: 31 days.
Average number of offspring: 5.5.
Average age at sexual or reproductive maturity (female)
Sex: female: 335 days.
Das Rotschwanz-Streifenhörnchen (Tamias ruficaudus, Syn.: Neotamias ruficaudus) ist eine Hörnchenart aus der Gattung der Streifenhörnchen (Tamias). Es kommt in den amerikanischen Bundesstaaten Washington, Idaho und Montana sowie im Süden von Alberta und British Columbia in Kanada vor.
Das Rotschwanz-Streifenhörnchen erreicht eine durchschnittliche Kopf-Rumpf-Länge von etwa 12,1 bis 12,8 Zentimetern, die Schwanzlänge beträgt etwa 9,8 bis 10,3 Zentimeter und das Gewicht etwa 57 bis 67 Gramm. Die Rückenfarbe ist Rot- bis Orangebraun und wie bei anderen Arten der Gattung befinden sich auf dem Rücken fünf dunkelbraune bis schwarze Rückenstreifen, die durch graue bis gelblich-weiße Streifen getrennt sind. Der Bauch ist weiß bis cremeweiß und die Unterseite des Schwanzes rotbraun bit einer schwarzen und rosafarbenen Begrenzung. Gegenüber den teilweise sympatrisch oder parapatrisch vorkommenden Unterarten des Kleinen Streifenhörnchens (Tamias minimus) und des Gelben Fichtenstreifenhörnchens (Tamias amoenus) ist das Rotschwanz-Streifenhörnchen etwas größer mit kräftigerem Schädel, zudem fehlt bei anderen Arten die auffällig rote Schwanzunterseite.[1]
Das Rotschwanz-Streifenhörnchen im Nordwesten von Washington, dem Norden von Idaho und dem Westen von Montana in den Vereinigten Staaten sowie im Süden von Alberta und British Columbia in Kanada vor.[1][2]
Rotschwanz-Streifenhörnchen kommen in verschiedenen Nadelwaldlebensräumen vor und leben vor allem in den offeneren Lichtungs- und Waldsaumbereichen mit dichterem Unterholz. Dabei kommt die Art zudem in verschiedenen Höhenlagen vor, die durch jeweils andere Nadelwald-Zusammensetzungen geprägt sind. Wichtig für das Vorkommen ist vor allem der dichte Unterwuchs, bodenliegende Äste und dichtes Buschwerk. Weite Teile des Verbreitungsgebietes weisen vor allem in Winter auch Schneeflächen auf.[1]
Die Art ist tagaktiv mit Hauptaktivitäten am frühen Morgen und am späten Nachmittag. Sie ist primär bodenlebend, kann jedoch auch in Bäume und Gebüsche klettern. Die Tiere ernähren sich vor allem herbivor von Samen und Früchten der Gräser, Büsche und Nadelbäume. Die Tiere sammeln die Nahrung in ihren Backentaschen und legen Nahrungsspeicher an. Die Nester der Art bestehen aus Pflanzenmaterial und Flechten. Sie sind meistens unterirdisch unter Steinen, herabgefallenen Ästen oder Baumstümpfen und wahrscheinlich als Bausysteme angelegt, es kommen jedoch auch oberirdische Nester in Bäumen und Gebüschen vor. Die Tiere überwintern vom Oktober bis zum April, sie sind entsprechend nur in den verbreitenden sechs Monaten aktiv. Kommunikation erfolgt vor allem zwischen den Jungtieren und der Mutter, sie ist jedoch nicht gut erforscht. Über die Bestandsdichten und die Größe der Territorien liegen nur begrenzte Daten vor.[1]
Die Paarungszeit liegt bei dieser Art im April bis Mitte Mai in geringeren Höhenlagen und etwas später in den Höhenlagen. Die Tragzeit beträgt etwa 31 Tage und die Jungtiere werden vom Ende Mai bis Ende Juni geboren. Der Wurf besteht dabei aus zwei bis sechs, meist vier bis sechs, Jungtieren.[1]
In Teilen des Verbreitungsgebietes kommt die Art sympatrisch mit anderen Streifenhörnchen wie dem Gelbes Fichtenstreifenhörnchen (Tamias amoenus) und dem Kleinen Streifenhörnchen (Tamias minimus) vor, wobei das Rotschwanz-Streifenhörnchen und das Kleine Streifenhörnchen in höheren Lagen als das Gelbe Fichtenstreifenhörnchen vorkommen.[3][1] Als Kleinsäuger werden die Tiere wahrscheinlich von verschiedenen Raubtieren wie Mardern, Katzen und Hunden sowie Greifvögeln und Schlangen erbeutet, konkrete Daten hierzu liegen allerdings nicht vor. Als Parasit ist bisher nur der Floh Ceratophyllus ciliatus dokumentiert.[1]
Das Rotschwanz-Streifenhörnchen wird als eigenständige Art innerhalb der Gattung der Streifenhörnchen (Tamias) eingeordnet, die aus 25 Arten besteht.[4] Die wissenschaftliche Erstbeschreibung stammt von dem amerikanischen Naturforscher Arthur Holmes Howell aus dem Jahr 1920, der es als Eutamias ruficaudus anhand von Individuen vom Upper St. Mary's Lake im Glacier County, Montana, beschrieb.[4][3] Innerhalb der Streifenhörnchen wird das Rotschwanz-Streifenhörnchen gemeinsam mit den meisten anderen Arten der Untergattung Neotamias zugeordnet, die auch als eigenständige Gattung diskutiert wird.[5]
Innerhalb der Art werden gemeinsam mit der Nominatform zwei Unterarten unterschieden:[1]
Die beiden Unterarten wurden teilweise aufgrund morphologischer Unterschiede des Schädels und des Penisknochens als eigene Arten betrachtet und auch neuere molekularbiologische Untersuchungen legen eine Trennung als zwei Arten nahe, wobei es zu Hybridisierungen beider Formen kommt. Hybridisierungen im Pleistozän sind zudem fossil über molekularbiologische Vergleiche auch mit anderen Streifenhörnchen, vor allem mit Tamias amoenus canicaudus, nachgewiesen.[1]
Das Rotschwanz-Streifenhörnchen wird von der International Union for Conservation of Nature and Natural Resources (IUCN) als „nicht gefährdet“ (Least Concern, LC) eingestuft. Begründet wird dies durch das relativ große Verbreitungsgebiet und das regelmäßige Vorkommen, bestandsgefährdende Risiken sind nicht bekannt.[2] Für den kanadischen Teil des Verbreitungsgebietes liegen nur begrenzt Daten vor, hier wird ein Gefährdungspotenzial angenommen.[1]
Das Rotschwanz-Streifenhörnchen (Tamias ruficaudus, Syn.: Neotamias ruficaudus) ist eine Hörnchenart aus der Gattung der Streifenhörnchen (Tamias). Es kommt in den amerikanischen Bundesstaaten Washington, Idaho und Montana sowie im Süden von Alberta und British Columbia in Kanada vor.
The red-tailed chipmunk (Neotamias ruficaudus) is a species of rodent in the family Sciuridae.[2] It is found in Alberta and British Columbia in Canada and Montana, Idaho and Washington in the United States.[1]
The red-tailed chipmunk is a large species with a total length of about 230 mm (9 in) including a bushy tail of 105 mm (4 in). The mass varies from about 54 g (1.9 oz) in the spring to 60 g (2.1 oz) in the fall. Females are marginally larger than males. The head is mottled grayish-brown with dark stripes above, through and below the eye. The body is basically orange-brown with five blackish stripes separated by four pale gray, tawny or cream-colored ones. The shoulders, sides, rump and flanks are tawny or buff. The underparts are creamy-white suffused with pinkish-buff. The upper side of the tail is black suffused with pinkish-buff and the underside is tawny tipped with pinkish-buff. In winter the animal's color is greyer and less tawny.[3]
In some areas, where range overlap with the yellow-pine chipmunk occurs, it may be difficult or impossible to distinguish the two species in the field; laboratory examination of skeletal structures may be required.[4][5]
The red-tailed chipmunk is native to southeastern British Columbia, southwestern Alberta, northeastern Washington, northern Idaho and western Montana. It is found at altitudes between 720 and 2,400 metres (2,360 and 7,870 ft) in coniferous forests, other woodland, forest edges, glades and bushy areas at the edge of upland meadows. It primarily lives on the ground but sometimes climb trees.[1]
The red-tailed chipmunk feeds mainly on seeds and berries and sometimes carries these in its cheek pouches.[3] Frequently eaten foods include the seeds of fir and pine, honeysuckle berries, cranberries, whortleberries, huckleberries, the seeds of locust trees and of snow brush, buckbrush, thistle, willow herb, grasses and many others types of seed. Dandelion flowers and leaves are sometimes eaten and the animal has been caught in traps baited with meat.[3] It does not hibernate but it may have periods of torpor.[3]
Breeding takes place in the late spring and summer, a litter size averaging five young born after a gestation period of about 31 days. Most nests are underground in a burrow but tree nests are occasionally used, often placed immediately underneath dense growths of dead twigs. The young first emerge from the nest when aged about 45 days.[3]
The red-tailed chipmunk (Neotamias ruficaudus) is a species of rodent in the family Sciuridae. It is found in Alberta and British Columbia in Canada and Montana, Idaho and Washington in the United States.
La ardilla rayada de cola roja Neotamias ruficaudus es una especie de roedor de la familia Sciuridae.
Se encuentran en Alberta y Columbia Británica, en Canadá, y en Montana, Idaho y Washington en los Estados Unidos
Datos: Q1770179
Multimedia:
Especies: Tamias ruficaudus
La ardilla rayada de cola roja Neotamias ruficaudus es una especie de roedor de la familia Sciuridae.
Tamias ruficaudus is een zoogdier uit de familie van de eekhoorns (Sciuridae). De wetenschappelijke naam van de soort werd voor het eerst geldig gepubliceerd door A.H. Howell in 1920.
De soort komt voor in Canada en de Verenigde Staten.
Bronnen, noten en/of referentiesTamias ruficaudus is een zoogdier uit de familie van de eekhoorns (Sciuridae). De wetenschappelijke naam van de soort werd voor het eerst geldig gepubliceerd door A.H. Howell in 1920.
붉은꼬리다람쥐(Neotamias ruficaudus)는 다람쥐과에 속하는 설치류의 일종이다.[2] 캐나다 앨버타주와 브리티시컬럼비아주, 미국 몬태나주와 아이다호주, 워싱턴주에서 발견된다.
붉은꼬리다람쥐는 대형 다람쥐로 붓꼬리 모양의 꼬리 길이 105mm를 포함하여 전체 몸길이가 약 230mm 정도이다. 몸무게는 봄에 약 54g부터 가을의 60g까지 다양하다. 암컷이 수컷보다 약간 큰 편이다. 머리에 회색빛 갈색 얼룩 반점이 있고, 짙은 줄무늬가 눈 위 아래로 나 있다. 몸은 기본적으로 오렌지색과 갈색을 띠며, 5줄의 검은 줄무늬와 4줄의 연한 회색, 황갈색 또는 크림색 줄무늬가 함께 이어진다. 어깨와 허리, 엉덩이와 옆구리는 황갈색과 담황색이다. 배 쪽은 분홍색이 감도는 크림색과 흰색이다. 꼬리 윗면은 분홍색과 담황색이 감도는 검은색이고, 아랫면은 황갈색이고 털 끝은 분홍색과 담황색을 띤다. 겨울에 털 색은 좀더 회색으로 변하고 황갈색을 덜 띤다.[3]
붉은꼬리다람쥐는 브리티시컬럼비아 주 남동부와 앨버타 주 남서부, 워싱턴주 북동부, 아이다호주 북부, 몬태나주 서부 지역의 토착종이다. 해발 720~2400m 고도의 침엽수림과 기타 산림 지대 가장자리, 고지대 목초지 가장자리의 습지와 덤불 지역 등에서 발견된다. 땅 위에서 주로 서식하지만 나무 위에 오르기도 한다.[1]
붉은꼬리다람쥐는 씨앗과 열매를 주로 먹고, 이를 볼주머니로 운반하기도 한다.[3] 전나무와 소나무, 인동덩굴 씨, 넌출월귤, 산앵도나무, 허클베리, 아까시나무, 세아노사, 갈매나무, 엉겅퀴, 분홍바늘꽃, 풀의 씨앗 등 여러 종류의 씨앗을 자주 먹는다. 서양민들레 꽃과 잎을 먹기도 하며, 붉은꼬리다람쥐가 고기를 덫으로 놓은 함정에 잡힌 적도 있다.[3] 겨울잠은 자지 않지만 활동을 하지 않는 기간을 갖는 것으로 추정된다.[3]
늦봄과 여름에 번식을 하고, 약 31일간의 임신 기간 이후에 평균 5마리의 새끼를 낳는다. 대부분의 둥지는 땅 아래 굴 속에 있지만, 나무 둥지를 사용하기도 하며 죽은 나뭇가지로 무성한 덤불 바로 아래에 둥지를 만들기도 한다. 새끼는 생후 약 45일 이후에 둥지 밖으로 처음 나온다.[3]
