Sylvilagus auduboniiAudubon's cottontail(Also: desert cottontail)

Geographic Range

This species can be found throughout much of southwestern North America, from northern Montana down to central Mexico, and as far west as the Pacific coast.

Habitat

This species is found mainly in arid regions, giving it the common name desert cottontail. It can also inhabit woodlands and grasslands, and it ranges in elevation from sea level up to about 6,000 feet. When not feeding, individuals live in heavy brush, brambles, or holes in order to hide from their many predators (coyotes, foxes, badgers, bobcats, hawks, etc.).

Physical Description

Female desert cottontails are slightly larger than males, weighing an average of 988 g while the average male weight is 841 g. For females, total length is about 385 mm, length of hind foot is 90 mm, and ear length is 73 mm. Males' measurements are similar. Both sexes have the bushy white "cotton" tail.

  • Average mass
    900 g
    31.72 oz
    AnAge
  • Average basal metabolic rate
    2.506 W
    AnAge

Reproduction

The breeding season is from December or January until the late summer. Gestation lasts only 28 days, and litters are made up of about three young. Pregnant females often resorb some of their embryos before gestation is complete, probably in response to environmental conditions. This species is somewhat less fecund than are others in the genus; desert cottontails produce only about 5 litters per year. A female builds a nest by digging a hole in the ground about 20 cm deep, then lining it with grass and fur. She feeds her young only once per day, by crouching over the nest to let them nurse. Their eyes open by day 10, and they leave the nest at the age of just under two weeks. They remain near the nest for another three weeks. Sexual maturity is achieved by the age of three months.

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Range number of offspring
    1 to 5
  • Average number of offspring
    3
    AnAge
  • Range gestation period
    26 to 30 days
  • Range weaning age
    21 to 28 days
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    164 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    107 days
    AnAge

Lifespan/Longevity

  • Average lifespan
    Status: captivity
    7.8 years
    AnAge

Behavior

Desert cottontails are not gregarious, but occasionally females have been seen feeding near one another without aggression. Home range size varies but is generally about 8 acres. The rabbits are most active in the early morning and in the evening, and they spend much of the remainder of the day under cover. When one is startled it may freeze or it may run for cover. They run in a zig-zag pattern, at about 15 miles per hour. This species has more athletic ability than the others in its genus, having the ability to swim and to climb trees and brush piles.

Communication and Perception

Food Habits

These rabbits eat almost exclusively grass (of various species). They will also eat some fruits, nuts, and vegetables when available.

Economic Importance for Humans: Positive

These animals are used for food and for their fur.

  • Positive Impacts
  • food
  • body parts are source of valuable material

Economic Importance for Humans: Negative

An area with a dense population of desert cottontails could be negatively impacted by their consumption of vegetation.

Conservation Status

This species is not threatened, although cattle grazing can affect its abundance.

Contributors

Deborah Ciszek (author), University of Michigan-Ann Arbor.

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

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

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.

dominance hierarchies

ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates

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.

folivore

an animal that mainly eats leaves.

food

A substance that provides both nutrients and energy to a living thing.

herbivore

An animal that eats mainly plants or parts of plants.

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.

sexual

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

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

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.

References

Chapman, J.A., and G.R. Willner. 1978. Sylvilagus audubonii. Mammailian Species No. 106, the American Society of Mammalogists.