Neotoma lepidadesert woodrat

Geographic Range

Neotoma lepida is found from southwestern Idaho and southeastern Oregon south through Nevada and western Utah. Neotoma lepida is also found in southern California, including the coastal region, and along the Baja California peninsula. Desert woodrats also occur on several islands in the Gulf of California. (Verts and Carraway, 2002)

Habitat

Neotoma lepida is often found in areas with succulent vegetation, which may be used as a water source. They prefer habitats with moderate to dense canopies. This species is found in juniper-sagebrush, creosote bush scrub, Joshua tree woodlands, scrub oak woodlands, and pinon-juniper woodlands. Neotoma lepida is abundant in rock outcrops, and rocky cliffs and slopes. (Brylski, 2000; Verts and Carraway, 2002)

Physical Description

Dorsal pelage of N. lepida ranges from pale, buffy-gray to dark-gray, and from cinnamon to black. The underside of N. lepida is white, as are the feet and throat. The tail is markedly bi-colored. (Verts and Carraway, 2002)

Neotoma lepida has a slender rostrum, and a narrow skull interorbitally. Neotoma lepida has no frontoparietal ridges, and the incisive foramina of this species are long and narrow. (Verts and Carraway, 2002)

N. lepida has a dental formula of 1/1, 0/0, 0/0, 3/3 = 16. The cheek teeth are hypsodont, and flat crowned. (Verts and Carraway, 2002)

The manus of N. lepida has 4 digits, and the pes has 5 digits. (Verts and Carraway, 2002)

Most body dimensions of N. lepida are sexually dimorphic. The total length feamles ranges from 281 to 392 mm, with males showing greater variation, and ranging in length from 276 to 407 mm. The tail length of females ranges from 122 to 192 mm, whereas males have a slightly longer tail of 129 to 198 mm. Hind foot lengths for females range from 27 to 38 mm. Males have hind foot lengths ranging from 28 to 38 mm. Ear length of females ranges from 27 to 38 mm, and of males ranges from 28 to 38 mm. Females weigh less than males, ranging from 122 to 240 g compared to the 132 to 350 g weight of males. (Verts and Carraway, 2002)

  • Sexual Dimorphism
  • male larger
  • Range mass
    122 to 350 g
    4.30 to 12.33 oz
  • Range length
    287 to 401 mm
    11.30 to 15.79 in
  • Average basal metabolic rate
    0.46 W
    AnAge

Reproduction

Sexual behavior in males requires that the females both emit attractive odors and engage in precopulatory behaviors. Mates may communicate by intense sniffing, vocalization, hop and dart and ear-wiggling responses, grooming, and foot thumping. Males show a pattern of multiple mounts and ejaculation. Although not specifically reported, the sexual dimorphism of these animals suggests that mating is polygynous. (Flemming, et al., 1981; Verts and Carraway, 2002)

Neotoma lepida breeds from October to May. The gestation period is 30 to 36 days, with an average litter size of 2.7 young. Although these animals have been observed to be polyestrous in lab, They probably breed only once per year in the wild. Weaning occurs between 27 to 40 days of age, and reproductive maturity is reached by 2 to 3 months of age. (Brylski, 2000; Egoscue, 1957)

  • Breeding interval
    Desert woodrats breed once yearly in the wild.
  • Breeding season
    Breeding occurs between October and May.
  • Average number of offspring
    2.7
  • Average number of offspring
    3
    AnAge
  • Range gestation period
    30 to 36 days
  • Range weaning age
    27 to 40 days
  • Range age at sexual or reproductive maturity (female)
    2 to 3 months
  • Range age at sexual or reproductive maturity (male)
    2 to 3 months

Nesting is solitary for N. lepida. Nests are made of dried vegetation. Females have a strong maternal instinct, and will readily accept orphaned young. Lactating females have been observed to be much more aggressive to intruders than males or non-lactating females. The role of males in parental care has not been documented. (Brylski, 2000; Verts and Carraway, 2002)

  • 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

Lifespan/Longevity

These animals apparently live around 3 years in the wild. (Egoscue, 1957)

  • Average lifespan
    Status: wild
    3 years
  • Range lifespan
    Status: captivity
    10.5 (high) years
    AnAge

Behavior

Neotoma lepida is aggressively solitary, although this aggressiveness apparently increases when a female has young. These rats may defend succulent plants and other water sources against other species as well as conspecifics. (Brylski, 2000; Egoscue, 1957; Verts and Carraway, 2002)

These animals are active yearlong. They are mainly nocturnal, but can be crepuscular, and occasionally diurnal. Neotoma lepida is known to move around different amounts, depending on habitat, from 14 m per night in coastal sage scrub to 80 m per night in sagebrush-juniper habitats. (Brylski, 2000; Egoscue, 1957; Verts and Carraway, 2002)

Houses of desert woodrats are made from twigs, sticks, cactus parts, or rocks. They prefer to build houses in rock crevices, bases of cactus, or in the lower branches of trees. (Brylski, 2000; Egoscue, 1957; Verts and Carraway, 2002)

Home Range

The home range size has not been reported.

Communication and Perception

Communication in this species is varied, and entails some chemical, tactile, visual, and accoustic components. Scent marking is sexually dimorphic in N. lepida. Males exhibit ventral rubbing more commonly than do females. Females exhibit rolling more than do males. Rubbing may occur in response to odors of conspecifics, after a male encounters a female, or in ares soiled by other individuals. Mates may communicate by intense sniffing, vocalization, hop and dart, and ear-wiggling responses, grooming, and foot thumping. (Brylski, 2000; Flemming, et al., 1981; Verts and Carraway, 2002)

Food Habits

Neotoma lepida is a follivorous/granivorous species. Food consists of buds, fruits, bark, leaves, and young shoots of many plant species. These rats move from their shelters to feeding areas, but carry food back to the shelters to consume it in safety. The paths that desert woodrats take to their food sources are often made up of boulders, which helps to conceal these animals from predators. (Brylski, 2000; Thompson, 1982; Verts and Carraway, 2002)

In coastal scrub habitat, preferred foods of N. lepida are live oak, chamise, and buckwheat. In the Mojave Desert, N. lepida prefers creosote, cholla, and prickly pear. These rats prefer mormon-tea, rattlesnake weed, mustard, sagebrush, and buckwheat in the juniper-sagebrush habitats. (Brylski, 2000; Thompson, 1982; Verts and Carraway, 2002)

  • Plant Foods
  • leaves
  • wood, bark, or stems
  • seeds, grains, and nuts
  • fruit
  • flowers

Predation

Neotoma lepida uses the cover of its house, or hides in boulders to escape predation. The main predators of N. lepida are coyotes (Canis latrans), swift fox (Vulpes velox), red-tailed hawks (Buteo jamaicensis), and great-horned owls (Bubo virginianus). N. lepida may also fall victim to conspecifics. (Brylski, 2000; Verts and Carraway, 2002)

Ecosystem Roles

Neotoma lepida competes with cricetid and heteromyid rodents, and therefore probably limits their populations. Their houses provide shelter for many small vertebrates. Because this species provides foodto snakes, owls, and many predatory mammals, it may influence their populations as well. (Brylski, 2000; Verts and Carraway, 2002)

Economic Importance for Humans: Positive

Neotoma lepida provides no direct economic benefit to humans. They are indirectly important to humans through their ecosystem roles.

Economic Importance for Humans: Negative

Neotoma lepida is a known carrier of hantavirus. (Verts and Carraway, 2002)

  • Negative Impacts
  • injures humans
    • carries human disease

Conservation Status

Neotoma lepida is not thought to be endangered at all, and is not listed by CITES or IUCN.

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Kurt Oelhafen (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor, instructor), University of Wisconsin-Stevens Point.

Glossary

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.

World Map

acoustic

uses sound to communicate

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.

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.

chaparral

Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.

chemical

uses smells or other chemicals to communicate

crepuscular

active at dawn and dusk

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

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.

fertilization

union of egg and spermatozoan

folivore

an animal that mainly eats leaves.

forest

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

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

island endemic

animals that live only on an island or set of islands.

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).

motile

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.

nocturnal

active during the night

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

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.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

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

soil aeration

digs and breaks up soil so air and water can get in

solitary

lives alone

tactile

uses touch to communicate

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).

terrestrial

Living on the ground.

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

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

viviparous

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

References

Brylski, P. 2000. "Desert Woodrat" (On-line). California Wildlife Habitat Relationship System. Accessed May 13, 2004 at http://www.dfg.ca.gov/whdab/html/M126.html.

Egoscue, H. 1957. The desert woodrat: a laboratory colony. Jornal of Mammalogy, 38: 472-481.

Flemming, A., P. Chee, F. Vaccarino. 1981. Sexual behavior and its olfactory control in the desert woodrat. Animal Behavioir, 29/3: 727-745.

Thompson, S. 1982. Spatial utilization and foraging behavior of the desert woodrat. Journal of Mammalogy, 63/4: 570-581.

Verts, B., L. Carraway. 2002. Neotoma lepida. Mammalian Species, 699: 1-12.