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. ("eNature", 2003; "Natural Diversity Information Source", 2004; "Oklahoma Museum of Natural History Mammal Key", 1989; "Utah Division of Wildlife Resources", 2004; Meaney and Armstrong, 1994; Wilson and Ruff, 1999)
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. ("Oklahoma Museum of Natural History Mammal Key", 1989; Cornely and Baker, 1986; Davis and Schmidly, 1997; Wilson and Ruff, 1999)
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. ("eNature", 2003; "Utah Division of Wildlife Resources", 2004; Davis and Schmidly, 1997; Davis, 1960; Meaney and Armstrong, 1994; Wilson and Ruff, 1999)
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. (Meaney and Armstrong, 1994)
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. (Davis and Schmidly, 1997; Meaney and Armstrong, 1994; "eNature", 2003; "Utah Division of Wildlife Resources", 2004; Davis and Schmidly, 1997; Davis, 1960; Meaney and Armstrong, 1994; Wilson and Ruff, 1999)
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. ("eNature", 2003; Davis, 1960; Wilson and Ruff, 1999)
The lifespan of this species is not known.
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. ("Oklahoma Museum of Natural History Mammal Key", 1989; "Oklahoma Museum of Natural History Mammal Key", 1989; Meaney and Armstrong, 1994; Wilson and Ruff, 1999)
Woodrats have a home range of about 20 to 25 yards from the den. (Palmer, 1954)
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. (Cornely and Baker, 1986; Palmer, 1954)
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. ("eNature", 2003; "Natural Diversity Information Source", 2004; "Utah Division of Wildlife Resources", 2004; Davis and Schmidly, 1997; Meaney and Armstrong, 1994; Palmer, 1954; Wilson and Ruff, 1999)
The known predators of Mexican woodrats are owls, foxes, coyotes, weasels, rattlesnakes, and bobcats. There are no anti-predator adaptations known for this species. (Ward and Ganey, 2003; Wilson and Ruff, 1999)
Neotoma mexicana is an important source of prey for owls, foxes, coyotes, bobcats, weasels and rattlesnakes. They also disperse seeds. (Peterson, et al., 2002; Ward and Ganey, 2003; Wilson and Ruff, 1999)
Although it is not documented as a common ocurrance, Mexican woodrats may serve as food for humans. (Davis, 1960)
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. (Fulhorst, et al., 2001; Peterson, et al., 2002)
This species does not have a conservation status because it is not threatened.
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.
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.
living in the southern part of the New World. In other words, Central and South America.
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.
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.
an animal that mainly eats leaves.
A substance that provides both nutrients and energy to a living thing.
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
an animal that mainly eats fruit
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.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
an animal that mainly eats fungus
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
breeding is confined to a particular season
reproduction that includes combining the genetic contribution of two individuals, a male and a female
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).
Living on the ground.
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
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
movements of a hard surface that are produced by animals as signals to others
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.
2004. "Natural Diversity Information Source" (On-line). Wildlife Mexican Woodrat Page. Accessed March 14, 2004 at http://ndis.nrel.colostate.edu/wildlifespx.asp?SpCode=050787.
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Davis, W. 1960. Mammals of Texas. Austin: Game and Fish Commission.
Edwards, C., R. Bradley. 2001. Molecular systematics and historical phylobiogeography of the Neotoma mexicana species group. Journal of Mammalogy, 83/1: 20-30.
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Howe, R. 1978. Agonistic behavior of three sympatric species of wood rats, Neotoma mexicana, Neotoma albigula and Neotoma stephensi. Journal of Mammalogy, 59/4: 780-776.
Meaney, C., D. Armstrong. 1994. Mammals of Colorado. Denver: University Press of Colorado.
Norris, D., B. Johnson, J. Piesman, G. Maupin, J. Clark, W. Black. 1997. Culturing selects for specific genotypes of Borrelia burgdorferi in an enzootic cycle in Colorado. American Society for Microbiology, 35/9: 2359-2364.
Palmer, R. 1954. Mammal Guide of North America North of Mexico. Garden City, NY: Doubleday and Company, Inc..
Peterson, A., V. Sanchez-Cordero, B. Beard, J. Ramsey. 2002. Ecologic niche modeling and potential reservoirs for chagas disease, Mexico. Emerging Infectious Diseases, 8/7: 662-667.
Reid, F. 1997. Field Guide to the Mammals of Central America and South Eastern Mexico. New York: Oxford University Press.
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Wilson, D., S. Ruff. 1999. Smithsonian Book of North American Mammals. Washington: Smithsonian Institute Press.