Perognathus fasciatusolive-backed pocket mouse

Geographic Range

Perognathus fasciatus is found in north central United States and south central Canada. (Manning and Knox, 1988; Riddle, 1999)


Olive-backed pocket mice reside in arid and semi-arid upland habitats. They are often found in thinly covered grasslands, and prairies that contain loose soil. They prefer forest edges, a habitat which provides the proper amount of cover, and are associated with blue gramma and wheat grass. (Bernhardt, 2002; Manning and Knox, 1988; Pefaur and Hoffman, 1974)

  • Range elevation
    2500 (high) m
    8202.10 (high) ft

Physical Description

Perognathus fasciatus is a small to medium-sized pocket mouse with long hind feet (measuring 16 to 19 mm). Individuals weigh between 8 and 14 g, and measure 125 to 143 mm from head to tail. (Riddle, 1999; Williams and Genoways, 1979)

The species takes its common name from the olive-gray fur on the dorsal part of the body. Thefur of the ventrum is light cream to white in color. Pelage coloration may vary slightly depending on the season and the age of an individual. Juveniles and adults that have freshly molted will be darker. This is because the hairs are tipped with black when they are new, but this tip often breaks off as the hair ages, givign an animals a more "buffy" look. Adults molt once a year, with males molting sooner than the females. (Williams and Genoways, 1979)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    8 to 14 g
    0.28 to 0.49 oz
  • Range length
    125 to 143 mm
    4.92 to 5.63 in


Olive-backed pocket mice are polygynous. (Turner and Bowles, 1967)

Breeding begins as the weather becomes warmer in late April or early May, and continues through late July or early August. Females are capable of producing two litters per year, consisting of three to six young. The gestation period is roughly one month long, and newborns are altricial. (Riddle, 1999; Turner and Bowles, 1967)

Information is not available on the duration of lactation for this species, nor the age of independence. However, these mice are very similar to other members of their genus, and so probably do not vary significantly from other members of their genus in regard to these characteristics. (Riddle, 1999)

  • Breeding interval
    Females of this species breed twice annually.
  • Breeding season
    Breeding occurs between April and August.
  • Range number of offspring
    2 to 9
  • Average number of offspring
  • Average gestation period
    4 weeks

Information on parental care in this species is lacking in the literature. Because P. fasciatus is a mammal, we know that the female cares for the young, providing them with milk. The young are altricial, and like most rodents, must grow within the safety of the nest until they are able to move around their habitat. While in the nest, the mother undoubtedly grooms and protects the young. Male parental care patterns are not known for this species. (Riddle, 1999)

  • Parental Investment
  • no parental involvement
  • altricial
  • pre-fertilization
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • protecting
      • female


There is only a small proportion of this species which lives longer than 12 to 14 months. (Williams and Genoways, 1979)

  • Range lifespan
    Status: wild
    12 to 14 months
  • Typical lifespan
    Status: wild
    12 to 14 months


Locomotion of P. fasciatus is quadrapedial. These animals mostly relying on using hind limbs in a hopping fashion and touching down front limbs for balance. In the presence of danger, thes mice exhibit ricocheting. This is when all four feet are used in unison to jump away. (Bernhardt, 2002; Manning and Knox, 1988)

Perognathus fasciatus is known to construct tunnel systems with several chambers. A typical tunnel system consists of a main tunnel and summer/winter caches. Constuction of the tunnel seems to be determined by its later use. The summer portion of the burrow averages 30 cm deep whereas the winter portion can be up to 200 cm deep. On average, the area covered by a burrow is 6 m. (Bernhardt, 2002; Manning and Knox, 1988)

Thes mice spend much of the day in the burrow and become active above ground only at night. They do not appear to hibernate but do become less active beginning in mid-fall. (Bernhardt, 2002; Manning and Knox, 1988)

Home Range

The size of the P. fasciatus home range has not been reported.

Communication and Perception

Information is not available on the communication patterns in this species. However, other members of the genus are known to communicate with vocalizations. Tactile communication is undoubtedly important, especially between mates, mothers and their young, and competitors. Scent cues are not uncommon in rodents, and are probably present in this species.

Food Habits

Pocket mice are mainly herbivorous and granivorous, feeding on grasses, forbs, and seeds. However, they do occasionally eat insects. Food is carried in cheek pouches until it can be transferred into the burrow. Food caching is common. (Manning and Knox, 1988; Pefaur and Hoffman, 1974)

  • Animal Foods
  • insects
  • Plant Foods
  • leaves
  • seeds, grains, and nuts


Owl pellets found containing P. fasciatus suggest that owls are major predators of this species. Carnivores (such as coyotes) and reptiles (such as rattlesnakes) are also known to feed on them. ("Pocket Mice", 2002)

Ecosystem Roles

Perognathus fasciatus is a host species for fleas, ticks, and mites. These animals also play a role as a prey species for owls, some carnivores, and some snakes. Through their caching behavior, they act as seed dispersers. ("Pocket Mice", 2002; Manning and Knox, 1988)

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

These animals are not known to be of economic importance to humans, although humans probably benefit from them because of their status as a prey species. Many animals that humans find interesting, such as owls and coyotes, prey upon these mice.

Economic Importance for Humans: Negative

In general, rodents (collectively) can cause a lot of damage to crops and are also known for carrying diseases, and for harboring parasites which carry diseases. No specific accusations have been made against P. fasciatus, but is probably guilty of some of these infractions against humans.

  • Negative Impacts
  • injures humans
    • carries human disease
  • crop pest

Conservation Status

Olive-backed pocket mice are not listed by CITES or IUCN.

Other Comments



Nancy Shefferly (editor), Animal Diversity Web.

Heidi Bossingham (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor), University of Wisconsin-Stevens Point.



living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map


uses sound to communicate


young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


uses smells or other chemicals to communicate


animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.


union of egg and spermatozoan


an animal that mainly eats leaves.


forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.


Referring to a burrowing life-style or behavior, specialized for digging or burrowing.


an animal that mainly eats seeds


An animal that eats mainly plants or parts of plants.


offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).


having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.


active during the night


having more than one female as a mate at one time


specialized for leaping or bounding locomotion; jumps or hops.

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season


remains in the same area


reproduction that includes combining the genetic contribution of two individuals, a male and a female


lives alone

stores or caches food

places a food item in a special place to be eaten later. Also called "hoarding"


uses touch to communicate


that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.


A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.


uses sight to communicate


reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.


Colorado Division of Wildlife. 2002. "Pocket Mice" (On-line ). Accessed 11/01/02 at

Bernhardt, T. 2002. "Olive-backed Pocket Mouse" (On-line ). Canadian Biodiversity Website. Accessed 11/01/02 at

Manning, R., J. Knox. 1988. Perognathus fasciatus. Mammalian species, 303: 1-4.

Pefaur, J., R. Hoffman. 1974. Note on the Biology of teh Olive-backed Pocket Mouse/Perognathus fasciatus/ on teh Northern Great Plains. The Prairie Naturalist, 6/1: 7-15.

Riddle, B. 1999. Olive-backed Pocket Mouse (Perognathus fasciatus). Pp. 497 in D Wilson, S Ruff, eds. The Smithsonian Book of North American Mammals. Washington and London: Smithsonian Institution Press.

Turner, R., J. Bowles. 1967. Comments on the Reproduction and Food Habitats of the Olive-backed Pocket MOuse in Western North Dakota. Transactions of the Kansas Academy of Science, 70/2: 266-267.

Williams, D., H. Genoways. 1979. A systematic Review of the Olive-backed Pocet Mouse/Perognathus fasciatus. Carnegie Museum of Natural History, 48/5: 73-102.