Hyemoschus aquaticuswater chevrotain

Geographic Range

The African chevrotain, also known as the water chevrotain, is endemic to tropical regions of the African continent. While its range is primarily restricted to coastal regions, this species occurs from Sierra Leone to western Uganda.

(Robin 1990, Nowak 1999)

Habitat

The African chevrotain can be found in tropical rain forests and thickets rarely more than 250 m away from water. At night, chevrotains can be observed in exposed clearings and open river banks but during the day, the animal cannot be found outside of the dense forest.

(Robin 1990, Kingdon 1979)

Physical Description

The water chevrotain is a small animal that resembles a deer (Cervidae). This species is larger than its Asian counterparts, maintaining a size similar to a rabbit. The water chevrotain has a body length of between 45 and 85 cm and a tail length ranging from 7.5 to 17 cm. Animals of this species weigh 7-15 kg, however, the average weight for males is only 9.7 kg, whereas females average 12 kg. The weight at birth is unknown.

Hyemoschus aquaticus has a small, pointed head and a stocky body set on slender, delicate legs. The rear of the body is wedge-shaped and slightly raised relative to the rest of the body. Neither sex has antlers, but males of the species have well developed sharp tusks that extend below the lips of the animal.

The pelage has stripes and spots that camouflage the animal within the shaded areas of the forest. The water chevrotain has white stripes on its head and neck and a white underside to its tail. It has large eyes, slit-like nostrils and medium-sized ears.

(Robin 1990, Nowak 1999)

  • Range mass
    7 to 15 kg
    15.42 to 33.04 lb
  • Average mass
    9.7-12 kg
    lb
  • Range length
    45 to 85 cm
    17.72 to 33.46 in

Reproduction

When a female enters estrus, she is courted by the male who follows her movements and makes vocalizations. The cry of the male stops the female's movement, at which point the male licks her genital area. This pattern is repeated over some time. The male mounts the female by laying his body over hers and copulation takes place.

The gestation period is 6 to 9 months, and females give birth to one young a year. Due to the presence of four mammae in the females of this species, researchers suggest that they are capable of larger litters. Water chevrotains give birth to precocial young, capable of standing within an hour after birth. Females spend most of their day apart from their young and meet only to suckle them. Lactation lasts 3-6 months and the young disperse from the mother's home range when they reach sexual maturity (between 9 and 26 months).

(Nowak 1999, Kingdon 1979)

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Average number of offspring
    1.25
    AnAge
  • Average gestation period
    175 days
    AnAge
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    403 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    403 days
    AnAge

Lifespan/Longevity

Behavior

Females are sedentary, occupying one home range throughout adult life. The female has a smaller home range than the male, approximately 13-14 ha in area. Males are solitary, occupying temporary home ranges of 20-30 ha. This range usually overlaps the home range of 2 females. Males only occupy a home range for at most a year, after which they are replaced by another male. Few aggressive behaviors have been observed within the species, and some researchers propose that this indicates a lack of social hierarchy. Short fights occasionally occur among males, who use their sharp canines to bite their opponent. The injuries sustained during these fights are the most likely cause of the general avoidance of conspecifics observed in these chevrotains.

While the population density ranges between 7.7 and 28 individuals per sq. km., chevrotains rarely come into contact with one another. Perhaps because of this, young animals seldom exhibit play activities.

Unlike other species within the Chevrotain family, the water chevrotain is exclusively nocturnal. Individuals rest during the day hidden by ground vegetation.

Females are much more active than males. Although water is used as a refuge from predators, they are not capable of swimming for extended periods of time.

(Robin 1990, Nowak 1999, Kingdon 1979)

Communication and Perception

Food Habits

This species is primarily herbivorous, feeding on the leaves, fruits, and buds of trees and shrubs. It has occasionally been observed eating insects, crustaceans and even small mammals. Like many herbivores, the water chevrotain has various adaptations to facilitate effective digestion of its low-nutrient diet. Chevrotains are considered to be true ruminants, with a 4-chambered ruminating stomach.

(Robin 1990, Dubost 1984)

Economic Importance for Humans: Positive

The water chevrotain is avidly hunted by humans. (Nowak 1999)

Economic Importance for Humans: Negative

H. aquaticus occupies tropical rain forests which are utilized by humans as a source of timber. Although currently classifies as near threatened, the protection of this species could cause negative economic effects to timber harvesters.

(Robin 1990)

Conservation Status

Overall numbers of this species are currently decreasing due to hunting by humans and habitat destruction for timber resources. It is unlikely that this species will survive the habitat destruction it currently faces. This species is classified as near threatened by the IUCN and the species is also listed under appendix III of CITES in Ghana.

(Kingdon 1979, Grubb 1993)

Other Comments

Individuals live to an age of 11-13 years. (Nowak 1999)

Contributors

Helen Edwards (author), University of Michigan-Ann Arbor, Phil Myers (editor), Museum of Zoology, University of Michigan-Ann Arbor.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

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.

chemical

uses smells or other chemicals to communicate

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.

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.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

scrub forest

scrub forests develop in areas that experience dry seasons.

sexual

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

sexual ornamentation

one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.

tactile

uses touch to communicate

References

Dubost, G. 1984. Comparison of the diets of frugivorous forest ruminants of Gabon. Journal of Mammalogy, 65(2): 298-316.

Grubb, P. 1993. Order Artiodactyla. Pp. 382 in D Wilson, D Reeder, eds. Mammal Species of the World (2nd ed). Washington: Smithsonian Institution Press.

Kingdon, J. 1979. East African Mammals, Vol III, Part B. N.Y.: Academic Press, Inc..

Nowak, R. 1999. Walker's Mammals of the World (6th ed.). M.D.: The John's Hopkins University Press.

Robin, K. 1990. Chevrotains. Pp. 118-123 in B Grzimek, ed. Grzimek's Encyclopedia of Mammals, Vol. 5. N.J.: McGraw-Hill Publishing Company.