Geographic Range
Neotoma mexicana
, or Mexican woodrats, is found in the Southwestern United States from northern Colorado
and southern Utah down through Arizona, New Mexico, Oklahoma, and Texas and into Central
Mexico and Guatemala.
- Biogeographic Regions
- nearctic
- neotropical
Habitat
Neotoma mexicana
lives in rocky areas and normally builds nests in the cracks and crevices of canyon
walls or boulders. Nests are also found in hollow trees or abandoned buildings. Mexican
woodrats live mostly in mountainous areas, but can also be found in deciduous forests.
One of the most common types of woodlands they are found in is piñon-juniper. Their
elevation ranges from 15 to 4025 meters. Because they use cracks in rocky slopes,
their dens are not very elaborate. They do, however, still accumulate sticks and other
rubbish around their dens. Dens can sometimes be located by noticing fecal pellets
because
Neotoma mexicana
defecates near its nest.
- Habitat Regions
- temperate
- tropical
- terrestrial
Physical Description
Neotoma mexicana
is grayish to brownish on its back and its underside is buff to white. It can be
distinguished from
desert woodrats
because the tail has two distinct colors. It is brown on top and white on the bottom.
The average body length of
Neotoma mexicana
is 300 mm and the average tail length is 125 mm. At birth, the animal weighs 9-12
grams and reaches 140-185 grams as an adult.
- Other Physical Features
- endothermic
- bilateral symmetry
Reproduction
Not much is known about the mating systems of the Mexican woodrat. Agonistic behavior
has been observed in the laboratory setting during mating. Also, males may make a
gasping sound when approaching a female to mate.
Mexican woodrats breed from March until May and usually produces two litters during
that time. Each litter can have 2-5 pups, and the gestation period is about 33 days.
The young are weaned anywhere from 4-6 weeks after birth. Females reach sexual maturity
at a younger age than males. After 1-2 months, females can reach sexual maturity and
even produce their own litters during that same breeding season. On the other hand,
males reach sexual maturity at around 8 months. Also,
Neotoma mexicana
experiences a post-partum estrus.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
- post-partum estrous
The young are found in a nest along with either an adult male or adult female, not
both. Not much is known about the care or investment provided by the parents, but
these animals are born underdeveloped and reach sexual maturity at 2 months for females
and 9 months for males. The time of weaning is 4-6 weeks.
- Parental Investment
- altricial
Lifespan/Longevity
The lifespan of this species is not known.
Behavior
Neotoma mexicana
is a solitary species and can be aggressive towards conspecifics. It collects many
items such as sticks, feathers, and bones and therefore has received the common name
of packrat. It is active year around and usually at night.
- Key Behaviors
- terricolous
- nocturnal
- motile
- solitary
- territorial
Home Range
Woodrats have a home range of about 20 to 25 yards from the den.
Communication and Perception
In general, woodrats communicate with squeals, and warning signals are made by thumping
the hind feet and vibrating the tail. Gasping or chirping sounds are made during mating.
Scentmarking by rubbing the ventral side and foot-thumping is also common in
Neotoma mexicana
as a means of communicating.
- Other Communication Modes
- vibrations
- Perception Channels
- visual
- tactile
- vibrations
- chemical
Food Habits
Neotoma mexicana
forages on the ground or may climb like other woodrats. This species is a dietary
generalist and eats nuts, berries, green vegetation, acorns, and fungi. They sometimes
store their food.
- Plant Foods
- leaves
- seeds, grains, and nuts
- fruit
- Other Foods
- fungus
- Foraging Behavior
- stores or caches food
Predation
The known predators of Mexican woodrats are
owls
,
foxes
,
coyotes
,
weasels
,
rattlesnakes
, and
bobcats
. There are no anti-predator adaptations known for this species.
Ecosystem Roles
Neotoma mexicana
is an important source of prey for owls, foxes, coyotes, bobcats, weasels and rattlesnakes.
They also disperse seeds.
- Ecosystem Impact
- disperses seeds
Economic Importance for Humans: Positive
Although it is not documented as a common ocurrance, Mexican woodrats may serve as
food for humans.
- Positive Impacts
- food
Economic Importance for Humans: Negative
Neotoma mexicana
is known to be one of the hosts of Chagas disease. One strain of the disease coincides
with the distribution of the Mexican woodrat. It is transmitted through blood and
causes infection in the organs and peripheral nervous system. Usually, the disease
is transmitted by blood feeding insects.
Neotoma mexicana
is also a carrier of the arroyo virus, one that attacks the central nervous system.
- Negative Impacts
-
injures humans
- carries human disease
Conservation Status
This species does not have a conservation status because it is not threatened.
Additional Links
Contributors
Matthew Wund (editor), University of Michigan-Ann Arbor.
Jill Ceitlin (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.
- 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.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- 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.
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- mountains
-
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
- 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).
- seasonal breeding
-
breeding is confined to a particular season
- 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.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- solitary
-
lives alone
- territorial
-
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
- visual
-
uses sight to communicate
- acoustic
-
uses sound to communicate
- vibrations
-
movements of a hard surface that are produced by animals as signals to others
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- vibrations
-
movements of a hard surface that are produced by animals as signals to others
- 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"
- food
-
A substance that provides both nutrients and energy to a living thing.
- herbivore
-
An animal that eats mainly plants or parts of plants.
- folivore
-
an animal that mainly eats leaves.
- frugivore
-
an animal that mainly eats fruit
- granivore
-
an animal that mainly eats seeds
- mycophage
-
an animal that mainly eats fungus
- 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.
- 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.
References
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