Peromyscus aztecusAztec mouse

Geographic Range

Peromyscus aztecus occurs in the mid- to high elevations in many mountain ranges in the highlands of Mexico and Central America. Aztec mice have been found in southwestern Jalisco, Michoacan, and central Veracruz, through the volcanic belt. These mice are found in the Mexican States of Puebla, Morelos, Hidalgo, Guerrero, Oaxaca, and Ciapas, as well as into Central America. (Vazquez, et al., 2001)


Aztec mice occur at elevations between 1,000 m to 2,700 m. Vegetation types in their habitat are variable, and dependon the location. In Michoacan, the vegetation consists of montane, boreal coniferous forests. In Jalisco, pine/oak habitat and cloud forest cover the area. In Guerrero, P. aztecus occupies the cloud, oak, and pine/oak habitat types. Juniper forests are the used area in volcanic regions. These rodents often occur in fields with poor cover and abandoned agricultural fields. (Vazquez, et al., 2001)

  • Range elevation
    1000 to 2700 m
    3280.84 to 8858.27 ft

Physical Description

Peromyscus aztecus is a medium sized member of the genus Peromyscus. Individuals weigh between 22 and 36 g, and are from 197 to 260 mm in length. The fur is a pale ochre with black dorsally. The flanks are reddish, and the under parts are light buff. A black ring around the eye is present. The feet are white. The tail is bicolored with a white tip and is about as long as the body. Other measurements include: hind foot, 22.5 to 29 mm; ear, 15.5 to 21.5 mm; average length of skull, 33.3 mm; and the average size of the rostrum, 13.8 mm (Vazquez, et al., 2001)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    22 to 36 g
    0.78 to 1.27 oz
  • Range length
    197 to 260 mm
    7.76 to 10.24 in


Aztec mice are monogamous. A male and female will form a pair, and participate in joint rearing of the young. (King, 1968)

Peromyscus aztecus breed throughout the year if it is not too cold or too hot. The peak of the reproductive season is March to July. Individuals become mature enough to mate at about the same time that they develop their sub-adult pelage. The normal gestation period of this species is about 21 to 27 days. The average litter size is reported to be 3.4. Time of weaning is 3 to 4 weeks. The reproductive performance may decline after 3 to 5 litters or when a female reaches about 18 months of age. Sexual behavior includes grooming, driving, mounting, intromission, and ejaculation. (King, 1968)

  • Breeding interval
    These mice can breed every month or so while weather conditions permit it.
  • Breeding season
    P. aztecus breeds from March to July.
  • Average number of offspring
  • Range gestation period
    21 to 27 days
  • Range weaning age
    3 to 4 weeks

Parental care is most demonstrated by the female. Mother mice provide milk, grooming, and protection for their altricial young until they are able to leave the nest. However, the male of a mated pair may stay at the nesting site to help the rearing of the young. Male parental behavior may include grooming the young and huddling over them to help keep them warm and safe. (King, 1968)

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


In the wild, most individuals probably won't live past 2 years. The longest known record of longevity for Peromyscus in a laboratory is 8 years and 4 month (Peromyscus maniculatus). (Vazquez, et al., 2001)

  • Typical lifespan
    Status: wild
    0.5 to 2 years


Aztec mice exhibit a variety of behaviors. As far as locomotion, walk and run on all four feet. They have contralateral limbs in synchrony, as well as quadrupedal ricochet. This means the hind and forelimbs strike alternately. Peromyscus aztecus is known to swim when necessary. In swimming, these mice have strong alternate kicking with hindfeet. The forefeet paddle, which keeps the head above the water. (King, 1968)

While exploring, these mice are hesitant, prone to freeze, and move with a tense, elongate body posture. They sleep in their nest during daylight hours. Their head is curled up under their body, and the tail is curled around the feet. During rest, their body temperature falls to a steady 3 degrees Celsius below normal. They are not known to hibernate, but they may become torpid and hypothermic in extreme cold. To overcome this, they shiver and raise their metabolic rate. In nest building and burrowing, they dig and gnaw. (King, 1968)

Home Range

Peromyscus aztecus has a wide home range from 0.1 acres to 10.0 acres. (King, 1968)

Communication and Perception

Tactile communication is used when grooming as a friendly interaction, as well as during biting in defense and aggression. Chemical communication is usually related to marking behavior. This involves olfactory methods of recognition. Visual communication is less important in this species because of their nocturnal activity. However, body postures probably communicate intent when two animals meet. These animals can detect movement in little light and see short distances in the dark. (King, 1968)

Food Habits

The diet of P. aztecus consists of many different things depending on their location and time of year. In Guerrero, they eat primarily grasses and seeds. In Jalisco, they eat monocot seeds in the dry-hot and cold seasons, and then dicot leaves in the wet season. Some other forms of food for P. aztecus may include insects, and dicot fruits. (Vazquez, et al., 2001)

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


Possible predators of P. aztecus include barn owls (Tyto alba), coyotes (Canis latrans), bobcat (Lynx rufus), and weasels (Mustela frenata). Aztec mice avoid predation by blending into their habitat, or they may run into burrows or crevices. (Vazquez, et al., 2001)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Aztec mice serve as food for many different predators. One negative role that P. aztecus may play in relationship to the ecosystem is the fact that they may retard forest regeneration. They are a force of destruction to seeds, specifically coniferous seeds. (King, 1968)

Economic Importance for Humans: Positive

An important role that P. aztcus may play economically for humans is that they may be used for many genetic and physiological studies in labs. They are clean, live well in the lab, are easily fed, and their reproductive rate is very high. (Nowak, 1995)

  • Positive Impacts
  • research and education

Economic Importance for Humans: Negative

There are many species of parasites that are found in relationship with the Peromyscus genus: pentastomids, acanthocephala, trematodes, cestodes (tapeworms), nematodes, mites, chiggers, ticks, fleas, lice, and diptera. Many of these parasites carry infectious diseases. Fleas may carry plague as well as typhus. (Nowak, 1995)

Conservation Status

Aztec mice are not listed by CITES or IUCN. ("IUCN Red List of Threatened Species", 2002; "Convention on International Trade in Endangered Species in Wild Fauna and Flora", 2002)

Other Comments

Currently, there are not a lot studies done on P. aztecus. The paper authored by Vazquez, et al., is a compilation of most of what is known about this species. (Vazquez, et al., 2001)


Nancy Shefferly (), Animal Diversity Web.

Eric Krueger (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


living in landscapes dominated by human agriculture.


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.

causes or carries domestic animal disease

either directly causes, or indirectly transmits, a disease to a domestic animal


uses smells or other chemicals to communicate


having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.


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.


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.


having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.


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 one mate at a time.


having the capacity to move from one place to another.


specialized for swimming

native range

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


active during the night


an animal that mainly eats all kinds of things, including plants and animals


Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

scrub forest

scrub forests develop in areas that experience dry seasons.


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


associates with others of its species; forms social groups.

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).


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

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.

year-round breeding

breeding takes place throughout the year


CITES. 2002. "Convention on International Trade in Endangered Species in Wild Fauna and Flora" (On-line ). Accessed 12/06/02 at

IUCN. 2002. "IUCN Red List of Threatened Species" (On-line ). Accessed 12/06/02 at

King, J. 1968. Biology of Peromyscus (Rodentia). The American Society of Mammologists.

Nowak, R. 1995. "White-footed Mice, or Deer Mice" (On-line). Walker's Mammals of the World, On-Line. Accessed November 18, 2002 at

Vazquez, L., G. Cameron, R. Medellin. 2001. Peromyscus aztecus. Mammalian Species, 649: 1-4.