Eastern chipmunk (Tamias striatus) — Vorstman's guide to the mammals of Europe

Tracks

No body of field signs for this species is known from Europe, because it lives free nowhere there. Signs from North America match those of the Siberian Chipmunk and may turn up with an escaped animal. The burrow entrance is a round hole 3 to 5 cm across under a stump, among tree roots, under a stone, wall or shed, and there is no spoil heap in front of it, unlike moles or steppe ground squirrels: the animal carries the soil away in its cheek pouches and scatters it elsewhere, so the entrance is inconspicuous. Underground lies a system with a nest chamber and store chambers that may hold several kilograms of seed. Above ground there are feeding places on a stump, stone or fallen log, with a small heap of stripped cone scales, gnawed nuts and acorn cups. The droppings are small, dark and shaped like rice grains. The call is a hard, drawn-out, many times repeated chock-chock-chock, and at an alarm a sharp trill.

Eastern chipmunk, burrow entrance in a lawn in quebec, with the animal half out of it: a round hole a few centimetres across with no spoil heap in front — the soil is carried away in the cheek pouches, so the pipe stays almost invisible — Burrow entrance in a lawn in Quebec, with the animal half out of it: a round hole a few centimetres across with no spoil heap in front — the soil is carried away in the cheek pouches, so the pipe stays almost invisible · Photo: Gilles Gonthier — CC BY 2.0 · Wikimedia Commons

Head close-up

Eastern chipmunk, head on, guelph, ontario: the dark stripe through the eye with a white stripe above and below it, and the small round untufted ears — **Head on, Guelph, Ontario: the dark stripe through the eye with a white stripe above and below it, and the small round untufted ears** · Photo: Ryan Hodnett — CC BY-SA 4.0 · Wikimedia Commons

Identification

A small, stocky ground squirrel of about 15 cm head-body, with a short, flat, bristly tail of just over 9 cm — less than two-thirds of body length — and a weight of about a hundred grams. The stripe pattern is the character. One dark mid-dorsal stripe runs from the shoulders to the rump, and on either side of it, on the rear half of the body, lie two dark stripes with a white to cream stripe between them; the forebody, shoulders and head are therefore much less marked than the back. The rump and tail base are rusty red to cinnamon and unstriped. Narrow dark stripes run through and above the eye, with white stripes above and below. The belly is white, the ears small, round and untufted. The cheek pouches are very capacious and often visibly full when the animal is collecting food. It lives on the ground: it climbs reasonably well, but runs across the forest floor with the tail held up at an angle and disappears into a burrow when alarmed.

Similar species

The only species with which confusion is likely is the Siberian Chipmunk, which is established in parts of France, Belgium and the Netherlands and is therefore almost always the correct identification in Europe. In that species five dark stripes run the full length of the back, from shoulders to rump, so that the rump is striped as well; in the Eastern Chipmunk the lateral stripes end on the rear half and the rump is plain rusty red. The American species is on average heavier and more thickset, though the measurements overlap. The Red Squirrel is two to three times as heavy, unstriped, has a bushy tail and lives in the canopy. The Garden Dormouse has a black mask round the eye instead of dorsal stripes and is nocturnal. For a striped rodent on the ground in Europe, the Siberian species is the starting point; only a photograph of the rump settles the identification.

Habitat

In North America broadleaved and mixed woodland with a closed canopy and much oak, beech and maple, preferably with a floor full of fallen logs, stones, walls and root plates to dig under; it also occurs in gardens, parks, cemeteries and shelterbelts and is a common garden animal in American suburbs. In Europe it has no habitat of its own: the animals present live in zoo enclosures or are temporarily at large in a residential area or wood edge near the place of escape.

Where the animal is most at home, classified with EUNIS — the European standard for habitats.

Distribution

Native to eastern North America, from south-eastern Canada and the Great Lakes to Louisiana and Georgia, with its centres in the Appalachians and the north-eastern hardwood forests. In Europe it is established nowhere. Within the guide area most records come from Germany; nearly all concern the free-ranging animals in an enclosure at Wuppertal Zoo. There are also scattered reports from the Netherlands, Sweden and Russia, which point to escaped or released cage animals. Breeding in the wild is not known from Europe. The species has never been deliberately released; it reached Europe only through the pet trade.

Established introduction
dark = core range, pale = thinly spread

Recording density, not a range: the map shows where the species is reported and draws no boundary around its range. The records of GBIF (2006-01-01 – 2026-12-31) are counted per 0.7° grid cell and divided by everything reported as a mammal in that same cell, so the number of observers does not shape the picture. Colour depth follows that share and fades out gradually, so the map does not follow national borders. Which of the four colours a cell takes is decided country by country from the literature, not from the records. Country outlines: Natural Earth (public domain).

Way of life

Strongly diurnal, with peaks in the morning and late afternoon. It eats acorns, beech mast, maple seed, hazelnuts, conifer seed, berries, fungi and animal food: insects, snails, worms, eggs and also frogs and nestlings. Food not eaten at once is carried in the cheek pouches to the underground store chambers; one animal was recorded carrying more than a hundred and twenty maple seeds at once. It is solitary and territorial within about fifteen metres of the burrow, with a home range of at most half a hectare. There are two litters a year, in late spring and summer, after a gestation of 31 to 32 days, averaging four or five young that come above ground at six weeks. It does not truly hibernate but enters winter torpor: it lies underground at a reduced metabolic rate and wakes every few days to feed from its store. In the wild it lives two to three years.

Where and when to look

In Europe this species is a matter of recognition during a chance encounter. For a striped chipmunk in a European wood, park or garden the Siberian species is the most likely; photograph the back and rump before recording it. Report an animal with a plain rusty, unstriped rump to the national recording scheme at once: it would be a new alien species at large, and with chipmunks an early report matters for intervention. In the wild the species can only be seen in eastern North America, where it occurs in almost every woodlot and on campsites.

Conservation status

Least Concern globally (LC, 2016); the assessment concerns eastern North America, where it is common, and says nothing about Europe, where it has no population. It is not on the Union list of invasive alien species under Regulation 1143/2014; the Siberian Chipmunk has been on that list since 3 August 2016. The difference lies in the history of introduction: the Siberian Chipmunk was sold and released as a pet in very large numbers from the 1960s to the 1980s and became established in France, Belgium and the Netherlands, whereas only single animals of the American species have escaped in Europe. The risks established for the Siberian species — it is a suitable host for ticks and raises the risk of Lyme disease, and it eats seeds, buds and birds' eggs — probably also apply to this species, which in its native range plunders nests to a greater extent.

Scientific name

Tamias striatus | (Linnaeus, 1758)

Linnaeus described the species in 1758 as Sciurus striatus; because it was later moved to another genus, the author and year stand in brackets. Tamias is Greek tamias, 'steward, one who stores up', after the animal's winter hoards. striatus is Latin for 'striped', from stria, 'furrow, stripe', after the five dark stripes over back and flanks. The specimen the first description was based on came from USA, Carolina.