The least chipmunk (''Neotamias minimus'') is the smallest species of
chipmunk
Chipmunks are small, striped rodents of the family Sciuridae. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia.
Taxonomy and systematics
Chipmunks may be classified either as ...
and the most widespread in North America.
Description
It is the smallest species of
chipmunk
Chipmunks are small, striped rodents of the family Sciuridae. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia.
Taxonomy and systematics
Chipmunks may be classified either as ...
, measuring about in total length with a weight of . The body is gray to reddish-brown on the sides, and grayish white on the underparts. The back is marked with five dark brown to black stripes separated by four white or cream-colored stripes, all of which run from the nape of the neck to the base of the tail. Two light and two dark stripes mark the face, running from the tip of the nose to the ears. The bushy tail is orange-brown in color, and measures long.
In some areas, where range overlap with the
yellow-pine chipmunk
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 ...
occurs, it may be difficult or impossible to distinguish the two species in the field; laboratory examination of skeletal structures may be required.
As in other chipmunks, there are four toes on each of the forefeet and five on the hindfeet. Females have eight
teat
A teat is the projection from the mammary glands of mammals from which milk flows or is ejected for the purpose of feeding young. In many mammals the teat projects from the udder. The number of teats varies by mammalian species and often corre ...
s. The
brain to body mass ratio
A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...
for least chipmunks is lower than that for other species of chipmunk living in the same area, suggesting that they prefer less complex environments.
Distribution and habitat
Least chipmunks are found through most of the western United States from northern
New Mexico
)
, population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano)
, seat = Santa Fe
, LargestCity = Albuquerque
, LargestMetro = Tiguex
, OfficialLang = None
, Languages = English, Spanish ( New Mexican), Navajo, Ker ...
and western
North
North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating Direction (geometry), direction or geography.
Etymology
T ...
and
South Dakota
South Dakota (; Sioux language, Sioux: , ) is a U.S. state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Lakota people, Lakota and Dakota peo ...
to eastern
California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...
,
Oregon
Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...
and
Washington
Washington commonly refers to:
* Washington (state), United States
* Washington, D.C., the capital of the United States
** A metonym for the federal government of the United States
** Washington metropolitan area, the metropolitan area centered o ...
, and throughout much of southern and western Canada from
Yukon
Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...
and southeastern
British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...
[Nagorsen, D.W. (2005). "Rodents and Lagomorphs of British Columbia". Royal BC Museum, Victoria, BC] to central
Ontario
Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...
, and into the Upper Peninsula of
Michigan
Michigan () is a state in the Great Lakes region of the upper Midwestern United States. With a population of nearly 10.12 million and an area of nearly , Michigan is the 10th-largest state by population, the 11th-largest by area, and the ...
and neighboring parts of
Wisconsin
Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...
and
Minnesota
Minnesota () is a state in the upper midwestern region of the United States. It is the 12th largest U.S. state in area and the 22nd most populous, with over 5.75 million residents. Minnesota is home to western prairies, now given over to ...
. Throughout this range, as many as 21 subspecies have been identified.
[ Less arboreal than other chipmunks,][ least chipmunks are commonly found in ]sagebrush
Sagebrush is the common name of several woody and herbaceous species of plants in the genus ''Artemisia''. The best known sagebrush is the shrub ''Artemisia tridentata''. Sagebrushes are native to the North American west.
Following is an alph ...
habitats and coniferous woodland, and along rivers, but they also occur in alpine meadow
Alpine tundra is a type of natural region or biome that does not contain trees because it is at high elevation, with an associated harsh climate. As the latitude of a location approaches the poles, the threshold elevation for alpine tundra gets ...
s, and on the edges of the northern tundra
In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless moun ...
.[
]
Behavior
Least chipmunks are diurnal and eat seeds, berries, nuts, fruits and insects. They mark areas depleted of suitable food with urine, and do not return to such patches afterwards. Home range
A home range is the area in which an animal lives and moves on a periodic basis. It is related to the concept of an animal's territory which is the area that is actively defended. The concept of a home range was introduced by W. H. Burt in 1943. He ...
s vary widely, and have been reported to vary from in northern Michigan[ to as much as in Colorado.] Because of their small size, least chipmunks are generally subordinate to yellow-pine chipmunk
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 ...
s, which are able to drive them away from food resources where food is plentiful. However, because they need to eat less food in order to survive, least chipmunks are more numerous where resources are scarce. They are agile animals, and have been recorded running at speeds of up to in natural conditions.
Predators include hawk
Hawks are bird of prey, birds of prey of the family Accipitridae. They are widely distributed and are found on all continents except Antarctica.
* The subfamily Accipitrinae includes goshawks, sparrowhawks, sharp-shinned hawks and others. Th ...
s, owl
Owls are birds from the order Strigiformes (), which includes over 200 species of mostly solitary and nocturnal birds of prey typified by an upright stance, a large, broad head, binocular vision, binaural hearing, sharp talons, and feathers a ...
s, and mustelid
The Mustelidae (; from Latin ''mustela'', weasel) are a family of carnivorous mammals, including weasels, badgers, otters, ferrets, martens, minks and wolverines, among others. Mustelids () are a diverse group and form the largest family in ...
s.
Least chipmunks spend the winter in burrows and also scatter-hoard food in numerous concealed pits beneath logs and similar cover. Burrows consist of a single chamber about across and tunnels in diameter, averaging in length. They have two to four entrances, often concealed by nearby rocks, and are typically about below the surface.[ During the summer they may construct temporary nests in trees from leaves and grass,] or appropriate hollows made by woodpeckers.[
Least chipmunks do not ]hibernate
Hibernation is a state of minimal activity and metabolic depression undergone by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It most ...
, or put on excess fat in the fall. Instead, they survive the winter by entering torpor
Torpor is a state of decreased physiological activity in an animal, usually marked by a reduced body temperature and metabolic rate. Torpor enables animals to survive periods of reduced food availability. The term "torpor" can refer to the time ...
for long stretches of time, waking to eat food cached in the burrow. How much of each winter they spend below ground in this manner depends on the latitude, varying from late November to mid March in Michigan to mid October to late April in northern Manitoba
Manitoba ( ) is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population o ...
.[
]
Reproduction
Females enter estrus
The estrous cycle (, originally ) is the set of recurring physiological changes that are induced by reproductive hormones in most mammalian therian females. Estrous cycles start after sexual maturity in females and are interrupted by anestrous p ...
within a week of emerging from their burrow in the spring, and mating typically takes place between March and May. Gestation lasts 28 to 30 days, with a single litter of three to seven young being born each year; females who lose their first litter soon after birth may, however, sometimes be able to breed again in the same year. The young are born hairless and blind, measuring about in length, and weighing . They are able to stand and open their eyes at 27 days, and are weaned at 36 days. They are sexually mature at one year, but do not always breed until their second year. They can live for up to six years in captivity.[
]
Gallery
Neotamias minimus on the first peak of Stawamus Chief (DSCF7696).jpg, ''Neotamias minimus'' (side)
Neotamias minimus on Stawamus Chief (DSCF7729).jpg, ''Neotamias minimus'' (front)
Chipmunk 2006.jpg, Least chipmunk
References
{{Taxonbar, from1=Q24662789, from2=Q1765515
Neotamias
Fauna of the Great Lakes region (North America)
Mammals of Canada
Mammals of the United States
Least concern biota of North America
Least concern biota of the United States
Mammals described in 1839
Taxa named by John Bachman