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). (Schmid and Smolker, 1998; Stony Brook State University of New York, 1999)
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) (Duke University Primate Center, 1999)
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)
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. (Duke University Primate Center, 1999)
Red-bellied lemurs live 20 to 25 years in the wild (Duke University Primate Center, 1999).
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).
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. (Duke University Primate Center, 1999; Nowak, 1999)
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). (Nowak, 1999; Preston-Mafham and Preston-Mafham, 1992)
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. (Preston-Mafham and Preston-Mafham, 1992; Stony Brook State University of New York, 1999; Preston-Mafham and Preston-Mafham, 1992; Stony Brook State University of New York, 1999)
These lemurs play a role in seed dispersal and germination from seeds contained in the feces (Dew & Wright 1998).
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.
There are no negative effects of red-bellied lemurs on humans.
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. (Nowak, 1999)
Rred-bellied lemurs have been used in many behavioral studies. The Malagasy names for these animals are: Tongona, Barimas, and Soamiera.
Nancy Shefferly (editor), Animal Diversity Web.
Alexis Zenner (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor), University of Wisconsin-Stevens Point.
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
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
ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
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.
union of egg and spermatozoan
an animal that mainly eats leaves.
A substance that provides both nutrients and energy to a living thing.
an animal that mainly eats fruit
An animal that eats mainly plants or parts of plants.
animals that live only on an island or set of islands.
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 one mate at a time.
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
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.
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
associates with others of its species; forms social groups.
uses touch to communicate
Living on the ground.
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
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.
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.