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.
Habitat
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.
- Terrestrial Biomes
- savanna or grassland
- forest
- scrub forest
- Other Habitat Features
- agricultural
- riparian
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
- Other Physical Features
- endothermic
- heterothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
Reproduction
Aztec mice are monogamous. A male and female will form a pair, and participate in
joint rearing of the young.
- Mating System
- monogamous
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.
- Key Reproductive Features
- iteroparous
- year-round breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
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.
- Parental Investment
- no parental involvement
- altricial
-
pre-fertilization
-
protecting
- female
-
protecting
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- male
- female
-
provisioning
-
pre-independence
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
Lifespan/Longevity
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
).
Behavior
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.
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.
- Key Behaviors
- terricolous
- fossorial
- natatorial
- nocturnal
- motile
- daily torpor
- social
Home Range
Peromyscus aztecus
has a wide home range from 0.1 acres to 10.0 acres.
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.
- Other Communication Modes
- scent marks
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.
- Primary Diet
- omnivore
- Animal Foods
- insects
- Plant Foods
- leaves
- seeds, grains, and nuts
- fruit
- Foraging Behavior
- stores or caches food
Predation
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.
- 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.
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.
- 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.
- Negative Impacts
- causes or carries domestic animal disease
Conservation Status
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.
Additional Links
Contributors
Nancy Shefferly (), Animal Diversity Web.
Eric Krueger (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor), University of Wisconsin-Stevens Point.
- Nearctic
-
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.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
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
-
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.
- savanna
-
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.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- scrub forest
-
scrub forests develop in areas that experience dry seasons.
- agricultural
-
living in landscapes dominated by human agriculture.
- riparian
-
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
- endothermic
-
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.
- heterothermic
-
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.
- 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.
- monogamous
-
Having one mate at a time.
- iteroparous
-
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).
- year-round breeding
-
breeding takes place throughout the year
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- altricial
-
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.
- fossorial
-
Referring to a burrowing life-style or behavior, specialized for digging or burrowing.
- natatorial
-
specialized for swimming
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- social
-
associates with others of its species; forms social groups.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- scent marks
-
communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- stores or caches food
-
places a food item in a special place to be eaten later. Also called "hoarding"
- cryptic
-
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.
- causes or carries domestic animal disease
-
either directly causes, or indirectly transmits, a disease to a domestic animal
- omnivore
-
an animal that mainly eats all kinds of things, including plants and animals
References
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 http://www.press.jhu.edu/books/walkers_mammals_of_the_world/rodentia/rodentia.muridae.peromyscus.html .
Vazquez, L., G. Cameron, R. Medellin. 2001. Peromyscus aztecus. Mammalian Species , 649: 1-4.
CITES. 2002. "Convention on International Trade in Endangered Species in Wild Fauna and Flora" (On-line ). Accessed 12/06/02 at http://www.cites.org/eng/resources/species.html .
IUCN. 2002. "IUCN Red List of Threatened Species" (On-line ). Accessed 12/06/02 at http://www.redlist.org/ .