There are fossils in North America of the ancestors of P. leucopus from the Oligocene Epoch, about 40 million years ago.
White-footed mice have keen eyesight, hearing, and sense of smell. They use their vibrissae (whiskers) as touch receptors. A distinctive behavior of white-footed mice is drumming on a hollow reed or a dry leaf with their front paws. This produces a long musical buzzing. It is unclear why white-footed mice do this.
Communication Channels: visual ; tactile ; acoustic ; chemical
Perception Channels: visual ; tactile ; acoustic ; chemical
White-footed mice are not endangered or threatened. They are abundant throughout their range.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
These mice carry deer ticks, which spread Lyme disease. They also may be a reservoir of Four-Corners disease. Their fecal matter contains hantavirus, the organism that causes this disease.
They also hinder the growth of trees such as oaks and pines because they eat so many of the seeds.
Negative Impacts: injures humans (carries human disease)
White-footed mice help spread various kinds of fungi by eating the sporing bodies and excreting spores. Forest trees' ability to take up nutrients is enhanced by the " mycorrhizal" associations formed by these fungi. For many temperate forest trees, these fungi have been shown to be an essential element in order for trees to prosper. White-footed mice also help control populations of some harmful insect pests, such as gypsy moths.
Positive Impacts: controls pest population
White-footed mice are often abundant where they occur and are important as prey items for many small predators.
Peromyscus leucopus is omnivorous. Diet varies seasonally as well as geographically and may include seeds, berries, nuts, insects, grains, fruits, and fungi. Since they do not hibernate, even in cold weather, in the fall they store seeds and nuts for the winter.
Animal Foods: insects
Plant Foods: leaves; wood, bark, or stems; seeds, grains, and nuts; fruit; flowers
Other Foods: fungus
Foraging Behavior: stores or caches food
Primary Diet: omnivore
White-footed mice are found throughout most of the eastern United States. The easternmost part of their range extends from Nova Scotia in the north to Virginia in the south. They occur as far west as Saskatchewan and throughout the plains states, extending through eastern Mexico to southern Mexico and the Yucatan peninsula.
(Wilson and Ruff, 1999)
Biogeographic Regions: nearctic (Native )
White-footed mice live in a wide variety of habitats but are most abundant in warm, dry forests and brushlands at middle elevations. They are the most abundant small rodent in mixed forests in the eastern United States and in brushy areas bordering agricultural lands. In the southern and western portions of their range they are more restricted in distribution, occurring mainly in wooded areas and semi-desert scrub near waterways. In southern Mexico they occur mainly in agricultural areas. They build nests in places that are warm and dry, such as a hollow tree or vacated bird's nest. Their home ranges vary from 1/2 to 1 1/2 acres with 4 to 12 mice per acre.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: chaparral ; forest ; scrub forest
Most white-footed mice live for one year in the wild. This means that there is an almost complete replacement of all mice in the population from one year to the next. Most mortality occurs in the spring and early summer.
Average lifespan
Status: wild: 1.0 years.
Range lifespan
Status: captivity: 3.0 (high) years.
Typical lifespan
Status: captivity: 1.5 (high) years.
Total length ranges from 150 to 205 mm and tail length from 65 to 95 mm. Weight ranges from 15 to 25 g. The upperparts of the body are pale to rich reddish brown and the belly and feet are white. In some parts of the range it is difficult to distinguish P. leucopus from other, closely related species, such as P. maniculatus, P. eremicus, P. polionotus, and P. gossypinus. They differ from P. eremicus by being larger and the soles of its hind feet are furred in the heel region. P. maniculatus has a generally longer tail that is distinctly bicolored, rather than indistinctly bicolored in P. leucopus. P. gossypinus can usually be distinguished by their longer hindfoot, greater than 22 mm, whereas P. leucopus is generally less than 22mm. P. polionotus is generally smaller than P. leucopus. Other North American species of Peromyscus can generally be distinguished from P. leucopus by tail length. ( http://sevilleta.unm.edu/animal/mammal/white-fotted_mouse.html, 1995; Lackey, et. al. 1985, Wilson and Ruff, 1999).
Range mass: 15.0 to 25.0 g.
Average mass: 23 g.
Range length: 150.0 to 205.0 mm.
Sexual Dimorphism: sexes alike
Other Physical Features: endothermic ; bilateral symmetry
Average basal metabolic rate: 0.213 W.
White-footed mice are active primarily at night and are secretive and alert, thus avoiding many predators. They are abundant in many habitats and are the major diet item of many small predators.
Known Predators:
Anti-predator Adaptations: cryptic
Males have home ranges that overlap with multiple females, providing access to multiple mating opportunities. Pups in a single litter often have different fathers.
Mating System: polygynandrous (promiscuous)
In northern populations of this mouse, breeding is seasonal, mostly occurring in spring and late summer or fall but extends from March through October. In southern populations breeding seasons are longer and in southern Mexico breeding occurs year round. The gestation period is from 22 to 28 days. Longer gestation periods may result from delayed implantation in females still nursing their young from a previous litter. Young are blind when born. Their eyes usually open about 2 weeks after birth, and the young are weaned about 1 week later. They are ready to mate at an average age of 44 days in northern populations and 38 days in southern populations. They can have 2 to 4 litters a year, each containing 2 to 9 young. The litter size increases with each birth, peaks at the fifth or sixth litter, then decreases. White-footed mice may live several years in captivity but in the wild there is almost complete population replacement each year. ( http:// sevilleta.unm.edu/animal/mammal/white-footed_mouse.html,1995, Wilson and Ruff, 1999).
Breeding interval: White-footed mice can have 2 to 4 litters per year.
Breeding season: White-footed mice breed from March to October, or throughout the year in the southern parts of their range.
Range number of offspring: 2.0 to 9.0.
Average number of offspring: 5.0.
Range gestation period: 28.0 (high) days.
Average gestation period: 22.0 days.
Average age at sexual or reproductive maturity (female): 44.0 days.
Average age at sexual or reproductive maturity (male): 44.0 days.
Key Reproductive Features: iteroparous ; seasonal breeding ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); viviparous
Average birth mass: 1.89 g.
Average number of offspring: 4.5.
Average age at sexual or reproductive maturity (female)
Sex: female: 73 days.
Young are born blind, naked, and helpless. Their eyes open at about 12 days old and their ears open at about 10 days old. Females care for and nurse their young in the nest until they are weaned. Soon after that the young disperse from their mother's range. If the young or the nest are endangered, female white-footed mice will carry their young one at a time to a safer location.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)
The white-footed mouse (Peromyscus leucopus) is a rodent native to North America from Ontario, Quebec, Labrador, and the Maritime Provinces (excluding the island of Newfoundland) to the southwestern United States and Mexico.[1] In the Maritimes, its only location is a disjunct population in southern Nova Scotia.[2] It is also known as the woodmouse, particularly in Texas.
Adults are 90–100 mm (3.5–3.9 in) in length, not counting the tail, which can add another 63–97 mm (2.5–3.8 in). A young adult weighs 20–30 g (0.7–1.1 oz). While their maximum lifespan is 96 months, the mean life expectancy for the species is 45.5 months for females and 47.5 for males. In northern climates, the average life expectancy is 12–24 months.[3] The species is similar to Peromyscus maniculatus.[4]
Female on a staghorn sumac
White-footed mice are omnivorous, and eat seeds and insects. They are timid and generally avoid humans, but they occasionally take up residence in ground-floor walls of homes and apartments, where they build nests and store food.[5] White-footed mice spend substantial time in trees and bushes, sometimes taking unoccupied old bird nests and building roofs on them.[6]
Like the North American deer mouse, this species may carry hantaviruses, which cause severe illness in humans. It has also been found to be a competent reservoir for the Lyme disease–causing spirochete, Borrelia burgdorferi.[7] The white-footed mouse is the favored host for the parasitic botfly Cuterebra fontinella.[8]
The white-footed mouse is one of the most common mouse species used as laboratory mice after the house mouse, and their domesticated version is called Peromyscus leucopus linville.[9] Such domesticated mice are also kept as pets[10][11] and have been bred to have many different colors.[12]
Native populations of P. leucopus in New York city are isolated by dense human infrastructure and are largely confined to small urban forest islands such as Prospect Park and Central Park.[13] The limited gene flow caused by human activities and coupled with a bottleneck event in urban populations has been powerful enough to lead to evolutionary divergence of urban white-footed mice.[13][14]
New York City mice exhibit local adaptations to diet-mediated selective pressures of urban habitats. Being opportunistic feeders, urban P. leucopus populations subside on food discarded by humans as a readily available source of nutriment, thereby consuming a lot more fat and carbohydrates than rural populations.[15] Results of a landscape genomics study showed evidence of positive selection in mitochondrial genes of urban mice that are responsible for lipid and carbohydrate breakdown and digestion.[15] Isolated P. leucopus populations inhabiting NYC parks show signs of molecular-level adaptation to urban food resources.[15] The differential evolution of metabolic processes in urban P. leucopus populations is thought to contribute to their success and survival in NYC urban forests.[15] Furthermore, the morphology of urban white-footed mice may be changing to adapt to alternative food sources. For instance, the teeth of white-footed mice in New York City are shorter than the teeth of rural mice.[15] This change in physical traits could be explained by the availability of higher-quality food sources in urban forests, which negates the need for long, powerful teeth.[15]
Urban populations of P. leucopus may be under unique selective pressures due to increased routine exposure to pollutants and toxins. A comparative transcriptome study found evidence of positive selection acting on the genes of urban mice that play major roles in detoxification and xenobiotic metabolism.[16] The genes under positive selection pressure include CYPA1A and Hsp90, which are known to be involved in the metabolism of foreign substances and drugs.[17] High concentrations of heavy metals such as lead and mercury in NYC park soils pose a unique selective pressure that likely led urban populations of P. leucopus to develop metabolic adaptations to the toxicity of urban forest environments.[16] Furthermore, exposure of pollutants is known to induce hypermethylation of DNA.[17] A study showed that in urban white-footed mice, a gene coding for a demethylase enzyme is under positive selection.[17] This means that urban populations of white-food mice that live in highly polluted environments uniquely benefit from an active demethylase enzyme that removes methyl groups from DNA.[17]
City-dwelling white-footed mouse populations are densely concentrated in isolated urban parks, which makes sperm competition a particularly powerful source of selection in urban environments.[18] Genetic studies have identified signs of molecular-level evolution of reproductive processes in urban white-footed mouse populations. Genes associated with spermatogenesis, sperm locomotion, and sperm-egg interactions in urban mice show a divergent pattern of regulation compared to their rural counterparts.[18] Therefore, the intensified sperm competition of dense mouse populations in urban forests has driven them to develop faster, more efficient sperm than that of rural mice.
Urban environments are saturated with large numbers of novel and familiar pathogens that are introduced by transportation, traffic, and trade.[19] The elevated occurrence of pathogens is a driver of directional selection in which genetic variants that more efficiently resist infection are favored. The outcome of this selection can be seen in genetic divergence between urban and rural P. leucopus populations at loci that regulate the innate immune response and inflammation.[20] Furthermore, a study has found evidence of positive selection acting on genes that modulate pathogen recognition in urban mice.[20] Immunoregulatory proteins that are found on T lymphocytes are overexpressed in urban mice when compared to rural populations.[20] These findings suggest that the immune systems of NYC white-footed mice may be evolving to recognize and respond to pathogens more efficiently. The divergence between rural and urban white-footed mice is especially prominent due to impeded gene flow between these populations, which is caused by landscape barriers including roads, highways, and pedestrian sidewalks.[21] Monitoring the strength of immune defenses in P. leucopus is of special importance because they are commonly infected with dangerous pathogens such as hantaviruses and Borrelia burgdorferi.[21]
The white-footed mouse (Peromyscus leucopus) is a rodent native to North America from Ontario, Quebec, Labrador, and the Maritime Provinces (excluding the island of Newfoundland) to the southwestern United States and Mexico. In the Maritimes, its only location is a disjunct population in southern Nova Scotia. It is also known as the woodmouse, particularly in Texas.
