Eulemur rubriventer

Geographic Range

Red-bellied lemurs, Eulemur rubriventer , live in the eastern rainforest zone of Madagascar (Nowak, 1999).

• Biogeographic Regions
• ethiopian ethiopian
  • native native

• Other Geographic Terms
• island endemic island endemic

Habitat

This lemur mainly inhabits rainforest regions, at medium to high altitudes (Macdonald, 1984; Nowak, 1999).

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• rainforest rainforest

Physical Description

Red-bellied lemurs are sexually dichromatic. Females have white bellies with white markings on the neck and chin, whereas males are mostly brown with dramatic white eye patches and a scent gland located on the forehead. Both sexes both have a black tail.

The head and body length is from 36 to 42 cm and the tail length is 46 to 54 cm. These lemurs usually weigh between 2 and 3 kg and are approximately the size of a house cat (SUNY, 1999; Schmid & Smolker, 1998).

• Other Physical Features
• endothermic endothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes colored or patterned differently

Reproduction

Red-bellied lemurs are one of the few lemur species to form monogamous pair bonds. These form the core of the social group, which typically consists of the mated pair and their offspring. (Duke University Primate Center, 1999)

• Mating System
• monogamous monogamous

Red-bellied lemurs have a gestation period of 127 days and give birth from September to October. There is usually a single young born, though twins sometimes occur, and birth weight is 60 to 70 grams. An estrous cycle lasts one month and estrous lasts 1 to 2 days (Schmid & Smolker, 1998). Mothers wean their young around the age of 5 months.

Sexual maturity is reached at about 2 years of age. (Duke University Primate Center, 1999)

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
• viviparous viviparous

Both male and female parents care for their offspring. The mother nurses and carries the infant for the first 2 weeks of life. From 2 weeks to 5 weeks of age, the young are cared for equally by both parents, although nursing is only accomplished by the mother. After 5 weeks of age, the mother often rejects the young, leaving the father to care for them until they are about 100 days old.

• Parental Investment
• altricial altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-independence
  • protecting
    • male

Lifespan/Longevity

Red-bellied lemurs live 20 to 25 years in the wild (Duke University Primate Center, 1999).

Behavior

Red-bellied lemurs are mainly diurnal. They are social, living in groups of 5 or fewer individuals, usually consisting of a mated pair and their offspring. Females are dominant over males and lead the group in foraging. Females have preferential access to food and chose their own mates. Red-bellied lemurs do not appear to be territorial. Grooming is an important way of maintaining social cohesion within the group. Lemurs use their lower incisors as a comb to groom troop members (Duke University Primate Center, 1999; Nowak, 1999; Preston-Mafham, 1992).

• Key Behaviors
• diurnal diurnal
• motile motile
• sedentary sedentary
• social social
• dominance hierarchies dominance hierarchies

Communication and Perception

As in other primate species, communication is complex and occurs in a variety of ways. In addition to vocal communication, E. rubriventer uses chemicals to communicate. The prominent forehead scent gland of males is used to help mark territories. Facial expressions and body postures are some of the visual signals these primates use in communication. Finally, tactile communication, through grooming, mating, play, and aggression, also occurs.

• Communication Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

The diet of red-bellied lemurs consists mainly of flowers, fruits and leaves of 67 identified plant species. They also eat some invertebrates. When they eat toxic millipedes, they drool on them first, which may help to neutralize the toxins so these invertebrates are edible. Red-bellied lemurs, as well as other lemur species, may also eat soil (Nowak, 1999; Preston-Mafham, 1992).

• Primary Diet
• herbivore herbivore
  • folivore folivore
  • frugivore frugivore

• Animal Foods
• insects

• Plant Foods
• leaves
• seeds, grains, and nuts
• fruit
• flowers

Predation

When feeding, red-bellied lemurs employ a sentinel to keep watch for predators. If a bird of prey or some other predator is detected, the sentinel will utter several low grunts. The other members of the group will either freeze for periods up to 15 minutes or they will take cover. The are preyed upon by fossas (the largest carnivore in Madagascar) and raptors (Preston-Mafham, 1992; Stony Brook State University of New York, 1999). They are also hunted by humans and taken by introduced dogs and cats.

Ecosystem Roles

These lemurs play a role in seed dispersal and germination from seeds contained in the feces (Dew & Wright 1998).

• Ecosystem Impact
• disperses seeds

Economic Importance for Humans: Positive

Red-bellied lemurs, as well as the other species of lemurs, are charismatic and unique animals, making them valuable for ecotourism. These animals have also been used in behavioral research. They are sometimes hunted for food.

• Positive Impacts
• food food
• ecotourism ecotourism
• research and education

Economic Importance for Humans: Negative

There are no negative effects of red-bellied lemurs on humans.

Conservation Status

All species in this genus are endangered. The red-bellied lemur is listed as vulnerable by IUCN and is on Appendix I of CITES. Populations are estimated between 10,000 and 100,000 animals, and are thought to be declining due to the rapid loss of rainforest habitat in Madagascar (Nowak, 1999). All members of the Lemuridae are listed as endangered by the U.S. Federal government.

Other Comments

Rred-bellied lemurs have been used in many behavioral studies. The Malagasy names for these animals are: Tongona, Barimas, and Soamiera.

Additional Links

Encyclopedia of Life

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Alexis Zenner (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor), University of Wisconsin-Stevens Point.

References

Dew, J., P. Wright. 1998. Frugivory and seed dispersal by four species of primates in Madagascar's eastern rain forest. Biotropica , 30/3: 425-437.

Duke University Primate Center, 1999. "Red-bellied lemurs" (On-line). Accessed October 11, 2001 at http://primatecenter.duke.edu/animals/redbellied/ .

Macdonald, D. 1984. The Encyclopedia of Mammals . New York: Facts on File.

Nowak, R. 1999. Walker's Mammals of the World, Sixth Edition . Baltimore and London: The Johns Hopkins University Press.

Preston-Mafham, R., K. Preston-Mafham. 1992. Primates of the World . New York: Facts on File Inc.

Schmid, J., R. Smolker. 1998. Lemurs of the Reserve Speciale d'Anjanaharive-Sud, Madagascar. Fieldana: Zoology , 90: 227-238.

Stony Brook State University of New York, 1999. "Eulemur rubriventer" (On-line). Accessed October 11, 2001 at http://info.bio.sunysb.edu/rano.biodiv/Mammals/Eulemur-rubriventer/ .

Wisconsin Regional Primate Research Center, November 28, 2001. "Primate Info Net: Red-bellied Lemur (*Eulemur rubriventer*)" (On-line). Accessed Sept. 1, 2002 at http://pin.primate.wisc.edu/factsheets/eulemur_rubriventer.html .