Mice
A mouse (plural: mice) is a small rodent characteristically having a pointed snout, small rounded ears, a body-length scaly tail and a high breeding rate. The best known mouse species is the common house mouse (Mus musculus). It is also a popular pet. In some places, certain kinds of field mice are locally common. They are known to invade homes for food and shelter.
Mice, in certain contexts, can be considered vermin which are a major source of crop damage, causing structural damage and spreading diseases through their parasites and feces. In North America, breathing dust that has come in contact with mouse excrement has been linked to hantavirus, which may lead to hantavirus pulmonary syndrome (HPS).
- HOUSE MOUSE
- DEER MOUSE
- WHITE-FOOTED MOUSE (WOODMOUSE)
- HARVEST MOUSE
- CACTUS MOUSE
- COTTON MOUSE
- WOODLAND JUMPING MOUSE
- CALIFORNIA MOUSE
HOUSE MOUSE
A house mouse (plural: mice) is a small rodent characteristically having a pointed snout, small rounded ears, a body-length scaly tail and a high breeding rate. The best known mouse species is the common house mouse (Mus musculus). It is also a popular pet. In some places, certain kinds of field mice are locally common. They are known to invade homes for food and shelter.
OVERVIEWHouse mice almost always live near humans, in or around houses and in fields. House mice should be controlled because they can transmit diseases, and their droppings can spoil foods. While rats are more harmful to humans than mice, mice cause far significantly greater damage to clothing, furniture, books, and many other household items. Mice may live alone or in groups. Female mice reach breeding age by around 6 weeks old, males reach breeding age by about 8 weeks old. Gestation takes about 18-21 days. There can be between 3-14 pups (mouse babies) per litter and females can produce between 5-10 litters per year.
DISEASESMice, in certain contexts, can be considered vermin which are a major source of crop damage, causing structural damage and spreading diseases through their parasites and feces. In North America, breathing dust that has come in contact with mouse excrement has been linked to hantavirus, which may lead to hantavirus pulmonary syndrome (HPS).
IDENTIFICATION & REGION
Species: Mus musculus
Origin: Europe via Australia
Breeding Cycle: 20 – 30 days
Diet: Omnivorous
Average Length (mm): without tail, max 115
Average weight (g): 15 – 20
mouse skull
Mice tend to avoid animals larger than themselves and rely heavily on their sense of smell and hearing to avoid predators. They tend to reach greatest densities in thick ground cover. The mouse diet of invertebrates and plants is seasonal.
Mice droppings are 3.9-7.6 mm long. Singular.
Mice are found throughout the United States and can be found in bush, pasture, farms and urban settings.
DEER MOUSE
Creative Commons Deer Mouse by Seney Natural History Association is licensed under CC by 2.0 DESCRIPTION
Deer mice measure 12 to 28 cm from nose to tail. They weigh 15 to 32 grams. Deer mice are named for their fur’s striking similarity to the coloration of deer fur. Their grayish-brown bodies gradually whiten at the belly and legs. The most telling characteristic is their bicolored tail which is dark and bottom is light. Many people refer to deer mice as “field mice.”
Deer mice are blind, pink and hairless at birth. They weigh 1 to 3 grams and begin to change color within 24 hours. On the third day after birth, the ears unfold. Eyes open within two weeks and young are weaned at four weeks. New fur exhibits faintly blue coloration, which fades as they grow older and disappears completely when deer mice are ready for sexual reproduction.
OVERVIEWThe scientific name for a deer mouse is Peromyscus. The species has 56 subspecies. They are all tiny mammals that are plentiful in number. The deer mouse is described as a small rodent that lives in the Americas and is closely related to the white-footed mouse, Peromyscus leucopus. Because the two species are extremely similar in appearance, they are best distinguished through red blood cell agglutination tests or karyotype techniques. The deer mouse can also be distinguished physically by its long and multicolored tail. Deer mice are very often used for laboratory experimentation due to their self cleanliness and easy care.
Deer mice are nocturnal creatures who spend the day time in areas such as trees or burrows where they have nests made of plant material. The pups within litters of deer mice are kept by the mother within an individual home range. The deer mice do not mingle in groups with their litters. During the development stages, the mice within one litter interact much more than mice of two different litters. Although deer mice live in individual home ranges, these ranges do tend to overlap. When overlapping occurs, it is more likely to be with opposite sexes rather than with the same sex. Deer mice that live within overlapping home ranges tend to recognize one another and interact a lot
DISEASESDeer Mice are know to carry the hantavirus.. Infected rodents shed the virus in their urine, saliva and droppings (feces). Hantavirus is a serious illness and can be fatal. Ehrlichiosis and babesiosis are also carried by the deer mouse, as well as Lyme Dusease.
IDENTIFICATION & REGIONSpecies: Peromyscus maniculatus
Origin: North and Central America
Breeding Cycle: 22-26 days
Diet: Omnivorous
Average Length (mm): 120-280
Average weight (g): 15-32
mouse skull
Deer Mouse Habitat in North America. The deer mouse is found throughout North America, preferring woodlands, but also appearing in desert areas.
Mice droppings are 3.9-7.6 mm long.
The droppings are smooth with pointed ends and measure 3 t0 6 mm in length and are difficult to distinguish from house mouse droppings, which are not known to be significant carriers of Hantavirus.
WHITE-FOOTED MOUSE (WOODMOUSE)
Creative Commons Captive White-Footed Mouse by Charles Homler is licensed under CC by 3.0 DESCRIPTION
Round and slender, ranging from 7 to 10 cm long in body length with a pointed nose and large, black beady eyes. Ears are large with little fur covering them. Body is bicolored with a light brownish-reddish top and white underbelly and feet. Tail is short, distinctly bicolored (dark on top and light on bottom), and covered with short, fine hairs and can be 5 to 13 cm in length.
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.
It has also been found to be a competent reservoir for the Lyme disease-causing spirochete, Borrelia burgdorferi
OVERVIEWThe 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 southwest 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.
White-footed mice are omnivorous, and eat seeds and insects. It is timid and generally avoids humans, but they occasionally take up residence in ground-floor walls of homes and apartments, where they build nests and store food.
DISEASESThis species is similar to Peromyscus maniculatus. Like the deer mouse, it 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.
IDENTIFICATION & REGION
mouse skull
The white-footed mouse is found throughout southern New England and the Mid-Atlantic and southern states, the midwestern and western states, and Mexico.
mouse droppings
It prefers wooded and brushy areas, although it will sometime inhabit more open ground.
HARVEST MOUSE
Creative Commons Harvest Mouse by Reg Mckenna is licensed under CC by 2.0
They have brownish fur with buff sides, a white belly, and an indistinct white stripe on the fur along the spine. Adults grow up to eleven to seventeen centimeters in length with a tail length of five to ten centimeters. Their height (from the ground to the highest point of their back) is between 1.5 and 2.0 centimeters. A mature mouse weighs anywhere from nine to twenty-two grams.
It is a nocturnal, with particularly intense activity on very dark nights. This mouse is particularly resourceful, making use of the ground runways of other rodents. It is also a very agile climber. Its primary food source is seeds, but springtime dining is augmented with new plant growth. In June, July and August the mouse is known to consume certain insects, especially grasshoppers and caterpillars. It stores seeds and other foodstuffs in underground vaults. Its many predators include the fox, weasel, coyote, hawk, snake and owl species.
Similar species are the plains harvest mouse, which has a more distinct but narrower stripe on its spine, and the fulvous harvest mouse, which has a longer tail. Also similar is the salt marsh harvest mouse, which has an underbelly fur that is more pinkish cinnamon to tawny. Finally, the house mouse has incisors without grooves, unlike those of the western harvest mouse.
OVERVIEWThe harvest mouse family is known for being very, and having long narrow tails. Harvest Mice are nocturnal like most rodents. They are known to have a two note call that can be heard at dusk.
The western harvest mouse (Reithrodontomys megalotis) is a small neotomine mouse native to most of the western United States. Its range extends from southwest British Columbia and southeast Alberta continuously to west Texas, northeast Arkansas, northwest Indiana, southwest Wisconsin, and the interior of Mexico to Oaxaca. Many authorities consider the endangered salt marsh harvest mouse to be a subspecies, but the two are now usually treated separately.
Breeding nests are spherical constructions woven from grass or other plant material. A nest is approximately 13 centimeters in diameter and lined with a more downy material of fibrous plants. A nest may have one or more entrances near its base. Most commonly, the nest is built on the ground in a protected area such as within a shrub or beside a fallen tree; however, the mouse will occasionally place the nest aboveground within a shrub.
It breeds from early spring to late autumn, with reduced activity at midsummer. The gestation period is 23 to 24 days. Repeated fertilization often occurs immediately after giving birth. It is not uncommon for a female to have ten to fourteen litters per annum, with a typical litter size of two to six individuals; however, litters of up to nine offspring can occur. Thus an annual production of forty to sixty young per female is normal. The newborn mice weigh approximately 1.0 to 1.5 grams.
DISEASESThis species can transmit plague, rat-bite fever and other serious illness. Mice can transmit bacterial infection worldwide. Caused by eating or drinking food or water that has been contaminated by mice feces, salmonellosis can cause severe dehydration due to vomiting, diarrhea, and fever in humans.
IDENTIFICATION & REGION
mouse skull
Found commonly in the southwest South Dakota, southeast Montana, to east Texas, Arizona, and north Mexico.
mouse droppings
CACTUS MOUSE
The range of masses given includes both male and females, as little research has been conducted on sexual dimorphisms in size. Average body length (not including the tail) is 8.0 to 9.0 centimeters and the average tail length is 10.0 to 14.0 centimeters (Parker 1990). This species is noted for its unusually long tail. A possible function for such a long tail is body temperature regulation (Hanney 1975).
The color of the thick pelage appears to vary. Parker remarks that Peromyscus eremicus has a pale gray back (1990). The Species Information Library, however, reports that species have been found in New Mexico with a spectrum of fur shades between pale yellowish and blackish (1994). A possible explanation is that two subspecies, one with darker fur (Peromyscus eremicus anthonyi) and lighter fur (Peromyscus eremicus eremicus) have interbred in New Mexico. Nowak describes the underparts of the cactus mouse as white or near-white (1991). The tail is usually less haired than that of other mice in its genus.
Cactus mice have naked soles on their hind feet, which distinguish them from other southwestern Peromyscus species. Facial and skull characteristics are also important in distinguishing the cactus mouse from other Peromyscus mice. Peromyscus eremicus has small ears and one to two upper molars with usually one mesoloph. The zygomatic arches of the skull are weak and not flared out and the auditory bulla are not greatly inflated (Species Information Library Peromyscus eremicus 1994). The nasal branches of the premaxillae extend posteriorly behind the nasals.
OVERVIEWCactus mice, averaging 3 inches in body length, live in burrows or rock crevices in their native desert habitat. These quick, agile climbers are noctural omnivores, foraging for seeds, insects and vegetation at night, while lowering their metabolism during the day to cope with extreme temperatures.
The cactus mouse (Peromyscus eremicus) is a species of rodents in the family Cricetidae. They are one species of a closely related group of common mice often called deer mice. Cactus mice are small, between 18 and 40 g in weight. Females weigh slightly more than males and are significantly larger in body length, ear length, length of mandible and bullar width of skull. An avarage cactus mice is 3 inches in lengnth. Cactus mice can be identified by having naked soles on their hind feet, and almost naked tails which are usually the same length or longer than the animals body length. Its ears are nearly hairless, large, and membranous. Their fur is long and soft; coloration varies between subspecies, as well as between different populations. Color of fur varies from ochre to cinnamon, with a white stomach, and the sides and top of head slightly grayish.Females tend to be slightly paler in color than males, while juveniles appear more gray than their parents.
Cactus mice are found in dry desert habitats in southwestern United States and northern Mexico, as well as islands off the coast of the Baja California peninsula and in the Gulf of Mexico. Low average temperatures and lack of mesquite (Prosopis juliflora) might limit northern expansion. The cactus mouse occurs sympatrically with four other mice species, including the California mouse, canyon mouse, Eva’s desert mouse and the mesquite mouse. The cactus mouse is nocturnal and feeds on seeds, mesquite beans, hackberry nutlets, insects, and green vegetation.
Cactus mice, like many desert mammals, aestivate when temperatures rise during the day: they lower their metabolism and enter a state of torpor that allows them to survive on very little water. They’re also fast for their size and can scale rock walls and trees–a trait that helps them evade predators like owls and rattlesnakes.
Cactus mice are restricted almost entirely to a desert habitat, especially where rocky outcrops or cliffs provide retreats and den sites.
Their food is largely seeds of various desert annuals, mesquite beans, hackberry nutlets, insects and green vegetation. Succulent plants provide water in areas where rain is infrequent.
Breeding in cactus mice colonies occurs from January-October and sometimes year-round. Litter sizes average one-four offspring, and females may have up to four litters per year. Young cactus mice are born with ears and eyes closed but develop rapidly. The species’ average life span is 1 year.
Peromyscus eremicus is nocturnal. The cactus mouse has been described as shy and excitable, and seldom bites when handled (Species Information Library Peromyscus eremicus 1994). In a study of running speed, four males and three females averaged a speed of 13.1 kilometers per hour (Djawdan and Garland 1988). Speed is important in more open habitats as a method of predator evasion. Cactus mice may enter a state of torpor during the day or aestivate during dry, hot times of the year.
DISEASESSpecies from Southern California have tested positive for hantavirus.
IDENTIFICATION & REGION
mouse skull
Cactus mice are found in dry desert habitats in southwestern United States.
mouse droppings
COTTON MOUSE
Adults are about 180 millimetres (7.1 in) long, with a tail of about 78 millimetres (3.1 in), and weigh 34-51 g. General appearance is very similar to the white-footed mouse, but the cotton mouse is larger in size and has a longer skull and hind feet. They have dark brown bodies and white feet and bellies.
The common name derives from the observed habit of using raw cotton in building nests.
One subspecies, the Chadwick Beach cotton mouse (P. g. restrictus) was last seen in 1938 and is now presumed extinct.
OVERVIEWThe cotton mouse occurs in the southeastern United States in an area roughly bordered by southeastern Virginia, Florida, Texas and Kentucky. It makes use of a variety of habitats, including hardwood forests, swamps, the margins of cleared fields, edges of salt savanna and dunes, scrub, and rocky bluffs and ledges. They probably prefer terrain that is regularly inundated.
Cotton mouse use underground refuges such as stump holes, tree cavity, root boles, and burrows where they can avoid predators and wild fires. Such underground refuges also provide lower temperature and humidity during the summer season as well.
Most Peromyscus species show great decrease in population after fire events through emigration, increase in predation, or from direct damage by fire from loss of habitat/protection. However, due to the behavior of using underground refuges, the cotton mice are to survive with no significant loss of population affected from the forest fire.
Cotton mice are omnivorous, and eat seeds and insects. Breeding may occur throughout the year, and usually occurs in early spring and fall. They may have four litters a year of up to seven young, which are helpless and naked at birth. Cotton mice are weaned at 20-25 days, and become sexually mature around two months. Lifespans are four to five months, with a rare few living to one year. They are preyed upon by owls, snakes, weasels, and bobcats.
The golden mouse (Ochrotomys nuttalli) has similar characteristics and share similar habitat and geographic regions with the cotton mouse. The coexistence of the two being possible when sharing similar habitat was due to their use of the common refuges had different daily and seasonal patterns. The cotton mouse showing broader selection in choosing refuges as they switch from one to the other is suggested to be the most significant component for such relationship to be possible.
Due to their small population size and reduced chances of reproduction, evidence for cotton mouse hybridizing with white-footed mouse has been found. Although they are known to be conspecific, hybridization will occur when there are limited option for reproduction. Identification was done through toe-clip sampling, and by analyzing the samples it was possible to find relationship of hybridization between the cotton mouse and the white-footed mouse(Peromyscus gossypinus megacephalus) based on a heterozygous GPI-1 marker. Additional evidence for hybridization was through comparison of body mass and hind foot length differentiating among areas scarce in cotton mouse population to higher populated areas.
DISEASESThis species can transmit plague, rat-bite fever and other serious illness. Mice can transmit bacterial infection worldwide. Caused by eating or drinking food or water that has been contaminated by mice feces, salmonellosis can cause severe dehydration due to vomiting, diarrhea, and fever in humans.
IDENTIFICATION & REGION
mouse skull
The cotton mouse (Peromyscus gossypinus) is a species of rodent in the family Cricetidae. It is found in the woodlands of the Southeastern United States.
mouse droppings
WOODLAND JUMPING MOUSE
Creative Commons Woodland Jumping Mouse by Dger is licensed under CC by 3.0
The Woodland jumping mouse is a medium-sized rodent and is similar to the Zapus mice but differs in having a white tail tip, brighter colors, and the lack of a small premolar in the upper jaw. Its sides are yellowish or reddish-brown peppered with black hairs. Dark-tipped hairs are intermixed with the dark brown dorsal band running from nose to tail. The underparts and feet are white. The species is darker in the south. The mouse has precise thermoregulation when active, deep seasonal hibernation, a high lower critical temperature, and a poor ability to tolerate high ambient temperatures which are likely adaptations to living in the cold.
The small, high-crowned skull displays large, oval infraorbital foramina, small auditory bullae, a short and broad palate, and narrow zygomatic arches. Three molariform teeth are present, premolars are absent, and grooved incisors are orange or yellow. Molars are rooted and semi-hypsodont. The tail is dark brown above and creamy white below with a white tip, and is sparsely haired, thin, tapered, and scaly. It is approximately 60% of total body length. Tail length is made possible by increased number and length of tail vertebrae. Long hind legs with elongated ankle bones and long toe bones make it possible for the mouse to leap and jump
OVERVIEWThe woodland jumping mouse (Napaeozapus insignis) is a species of jumping mouse found in North America. It can hop surprisingly long distances, given its small size. The mouse is an extraordinary part of the rodent family. Its scientific name in Latin is Napaeozapus insignis, meaning glen or wooded dell + big or strong feet + a distinguishing mark. This mammal can jump up to 3 m (9.8 ft) when scared, using its extremely strong feet and long tail.
Summertime is the peak activity period of the woodland jumping mouse. During this time, the mating season begins; mice that re-emerged from hibernation eat lots of food to restore body weight and fat. Some mice start to hibernate as early as September, but most wait until late November. The mice gather food and fat for more than 2 weeks before they plan to hibernate. During hibernation, body temperatures usually drop from 37 to 2 °C (99 to 36 °F). Even during their hibernation, they wake up about every 2 weeks to urinate or eat from their food stashes. Only about 1/3 of all mice that enter hibernation survive; the rest either die from hypothermia or are eaten by predators. Some mice do not enter hibernation, but move to nearby peoples’ houses to live inside the walls, in old furniture, or cabinets. They eat scraps or foods that were left over. The mice that do hibernate and survive usually re-emerge around April.
The woodland jumping mouse will live in either nests or burrows. The nests are usually found in hollow logs, under roots of trees or under rocks. The burrows can be found almost anywhere, although they are usually by a plant that can cover the entrance. Their nests are made from soft grasses, reeds and leaves. The burrows usually have multiple chambers, each one dug for a different reason. There is usually a room filled with nesting materials such as grass, reeds and leaves, which is used for sleeping or hibernation. Second, most mice have a room where they store and horde food for hibernation. And finally, there is, in most cases and room with some nesting material for mating, and where the juveniles will be nursed.
Little is known about territory size and territorial behavior because observation is difficult in the wild. Males are thought to have home ranges between 0.4-3.6 ha (0.99-8.90 acres) and females between 0.4-2.6 ha (0.99-6.42 acres) with ranges of the sexes overlapping. High numbers of mice are attracted to sudden and temporary food supplies (such as ripened berries) but what appears to be a colony established in the vicinity of the food may only be a temporary camp while the supply lasts. The average population density, in favorable habitat, is 7.5 per ha. Population density estimates range though from 0.64 to 59 per ha.
DISEASESMice are known to transmit Lyme disease, Salmonella, Typhus, Plague, and other harmful diseases.
IDENTIFICATION & REGION
mouse skull
Woodland jumping mice, Napaeozapus insignis, are found throughout northeastern North America,
mouse droppings
CALIFORNIA MOUSE
Creative Commons Peromyscus Californicus by Whatiguana is licensed under CC by 3.0
The California mouse has very large ears, and its tail is longer than the head and body combined. Including the tail, which is about 117 to 156 mm long, the mouse ranges in length from 220 to 285 mm. The coat is overall brown, mixed with black hairs. This dorsal colour shades to a creamy-white belly colour. The manus and feet are white. Adults are large enough that they can be confused with juvenile pack rats.
OVERVIEWThe California mouse (Peromyscus californicus) is a species of rodent in the family Cricetidae. It is the only species in the Peromyscus californicus species group. It is found in northwestern Mexico and central to southern California. It is largest Peromyscus species in the United States.
While most rodents are polygamous, the California mouse pair bonds, making it a model organism for researchers studying the genetics and neurobiology of partner fidelity and paternal care.
The California mouse is semiarboreal, but tends to nest on the ground, under debris such as fallen logs. Nests are insulated with coarse, dry grasses, weeds, and sticks, and fine grass is used as bedding in the center chamber. P. californicus is more strongly territorial than P. maniculatus, with both sexes defending the nest site. Males are also aggressive toward one another; their fighting techniques involve jumping, avoidance, and a characteristic mewing cry.
The California mouse pair bonds and the males help raise the young. A litter usually consists of only two pups, but a pair may produce as many as six litters in a year. Gestation ranges from 21 to 25 days. Weaning occurs when the offspring are five to six weeks of age.
The mouse’s diet consists of shrub fruits, seeds, and flowers, such as of Rhus integrifolia, Lotus scoparius, and Salvia apiana. They will also consume grasses, forbs, fungi, and arthropods.
California mice are mostly active at night. Their main predators are weasels and barn owls.
In foraging behavior, this may be the most specialized of the California Peromyscus species. California mice apparently competitively exclude P. truei from woodrat nests. The California mouse is largely sympatric with Neotoma fuscipes and P. truei. Fire favors P. maniculatus over P. californicus. Predators include weasels, coyotes, owls, snakes, and feral cats.
DISEASESMice are known to transmit Lyme disease, Salmonella, Typhus, Plague, and other harmful diseases.
IDENTIFICATION & REGION
mouse skull
Major foods include fruits, flowers and seeds of a variety of plants, fungi, and arthropods. In woodland habitats, acorns are eaten, but the seeds of California bay are the major food (Merritt 1974). Laboratory studies have shown that P. californicus is capable of cracking the seed coats of California bay, while P. truei cannot (Merritt 1974).
mouse droppings