The western jumping mouse (''Zapus princeps''), is a species of
rodent
Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...
in the family
Zapodidae
Zapodidae, the jumping mice, is a family of mouse-like rodents in North America and China.
Although mouse-like in general appearance, these rodents are distinguished by their elongated hind limbs, and, typically, by the presence of four pairs o ...
. It is found in
Canada
Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
and the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
.
Western jumping mice evolved during the
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...
, possibly from the fossil species '' Zapus burti'', which is known from the late
Blancan
The Blancan North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 4,750,000 to 1,806,000 years BP, a period of .Pacific jumping mice, with which they can still interbreed to produce fertile offspring.
Description
Western jumping mice resemble typical mice in appearance, but with long hind-feet and reduced forelimbs. They range from in total length, including a tail long, and weigh from . The mouse has coarse, dark-greyish-brown fur over the upper body, with a broad yellow to red band along the flanks, and pale yellowish-white underparts. Some individuals have white spots on the upper body, or on the tip of the tail. The two sexes are similar in appearance and size; females have four pairs of
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 corr ...
s.
Distribution and habitat
Western jumping mice are found in western North America from
Yukon
Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...
to
New Mexico
New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...
. They inhabit mountainous terrain with moderately damp climates, in meadows and forests dominated by
alder
Alders are trees of the genus ''Alnus'' in the birch family Betulaceae. The genus includes about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species ex ...
,
aspen
Aspen is a common name for certain tree species in the Populus sect. Populus, of the ''Populus'' (poplar) genus.
Species
These species are called aspens:
* ''Populus adenopoda'' – Chinese aspen (China, south of ''P. tremula'')
* ''Populus da ...
, or
willow
Willows, also called sallows and osiers, of the genus ''Salix'', comprise around 350 species (plus numerous hybrids) of typically deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions.
Most species are known ...
. They are commonly found in areas of dense vegetation close to fresh water.
Eleven
subspecies
In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...
are currently recognised:
* ''Zapus princeps princeps'' – eastern
Wyoming
Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...
,
Colorado
Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...
, northern New Mexico
* ''Z. p. chrysogenys'' –
La Sal Mountains
The La Sal Mountains or La Sal Range is a mountain range located in Grand and San Juan counties in the U.S. state of Utah, along the border with Colorado. The range rises above and southeast of Moab and north of the town of La Sal. This range i ...
* ''Z. p. cinereus'' – southeastern
Idaho
Idaho ( ) is a landlocked U.S. state, state in the Pacific Northwest and Mountain states, Mountain West subregions of the Western United States. It borders Montana and Wyoming to the east, Nevada and Utah to the south, and Washington (state), ...
and northwestern Utah
* ''Z. p. curtatus'' – northwestern
Nevada
Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, th ...
* ''Z. p. idahoensis'' – northern Idaho, western
Montana
Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an ...
, central Wyoming
* ''Z. p. kootenayensis'' – southern
British Columbia
British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...
, northwestern
Washington
Washington most commonly refers to:
* George Washington (1732–1799), the first president of the United States
* Washington (state), a state in the Pacific Northwest of the United States
* Washington, D.C., the capital of the United States
** A ...
* ''Z. p. minor'' – from southern
Alberta
Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...
to northeastern
South Dakota
South Dakota (; Sioux language, Sioux: , ) is a U.S. state, 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 Dakota people, Dakota Sioux ...
* ''Z. p. oregonus'' –
Oregon
Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...
California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...
* ''Z. p. saltator'' – British Columbia to southern Yukon
* ''Z. p. utahensis'' –
Utah
Utah is a landlocked state in the Mountain states, Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northea ...
and western Wyoming
Biology
Western jumping mice are
omnivore
An omnivore () is an animal that regularly consumes significant quantities of both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize t ...
s, with the largest part of their diet consisting of the seeds of grasses and herbs. Less important food items include fruits, fungi, and insects. Population densities range from , with individual mice having home ranges between , with males generally having larger ranges than females. The feeding grounds of mice can be identified by small piles of grass stems stripped of their seeds, and by the presence of clear runways strewn with grass clippings. Their nests are constructed from grass fragments, and are concealed beneath vegetation or debris.
The mice are
nocturnal
Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite.
Nocturnal creatur ...
, but are only active for the summer months, hibernating for the rest of the year. In at least some areas, they spend between eight and ten months of the year hibernating. They subsist entirely on their fat reserves while dormant, and do not cache food; a typical mouse may lose 25% of its body weight during the eight to ten months of its hibernation. However, the hibernation is not continuous throughout this period, with the mice waking, on average, once every 38 days.
The timing of hibernation is related to the weather conditions, with mice entering their dens following the first snowfall, if they have not already done so earlier in the year. They awake once the ground temperature reaches
Predators include
bobcat
The bobcat (''Lynx rufus''), also known as the wildcat, bay lynx, or red lynx, is one of the four extant species within the medium-sized wild cat genus '' Lynx''. Native to North America, it ranges from southern Canada through most of the c ...
s,
weasel
Weasels are mammals of the genus ''Mustela'' of the family Mustelidae. The genus ''Mustela'' includes the least weasels, polecats, stoats, ferrets, and European mink. Members of this genus are small, active predators, with long and slend ...
s,
skunk
Skunks are mammals in the family Mephitidae. They are known for their ability to spray a liquid with a strong, unpleasant scent from their anal glands. Different species of skunk vary in appearance from black-and-white to brown, cream or gi ...
s,
raccoon
The raccoon ( or , ''Procyon lotor''), sometimes called the North American, northern or common raccoon (also spelled racoon) to distinguish it from Procyonina, other species of raccoon, is a mammal native to North America. It is the largest ...
s, snakes and birds of prey. The mice flee predators by making a rapid series of long jumps, interspersed with short periods when they freeze in place. Although they normally move by making short hops and occasional leaps of up to , when startled, their leaps may reach along the ground, and into the air.
Reproduction
Female western jumping mice enter
estrus
The estrous cycle (, originally ) is a set of recurring physiological changes induced by reproductive hormones in females of mammalian subclass Theria. Estrous cycles start after sexual maturity in females and are interrupted by anestrous phas ...
within one week of emerging from the hibernation, and typically breed only once each year. Gestation lasts for eighteen days, and results in the birth of a litter of four to eight young. The pups are born blind and hairless, weighing about . They are weaned between 28 and 35 days of age.
They are apparently able to breed by the time they complete their first hibernation, although only around 40% do so, with the remainder waiting for a further year. They live for three to four years.