The red-bellied lemur can be found foraging at all levels of the forest, including the ground (4), and has been recorded feeding on over 70 different plant species over the course of a year, including the introduced Chinese guava (Psidium cattleyanum) (2). It feeds mainly on fruits but will also feed on flowers and leaves depending on the season (2) (5). Invertebrates such as millipedes also make up a small proportion of their diet (2). The red-bellied lemur is cathemeral (2), but activity patterns vary and are related to the availability of preferred foods (4). Although groups have been observed with more than one adult of each sex, red-bellied lemurs generally live in small family groups of two to six individuals, comprising an adult pair and their dependant offspring (2). Led by the dominant female, these groups travel and feed as single units throughout their 10 to 20 hectare home range, which is relatively small compared to other large-bodied lemur species (2) (5). Despite being one of the more territorial lemurs and actively defending their home range (4), neighbouring groups of red-bellied lemurs rarely show aggressive behaviour to each other (2). Females give birth to a single infant each year between September and October (2) (5). Mortality rate in infants is high, being around 50 percent (5). Initially, the female carries the young on her belly, and then later the infant moves around to be carried on its mother's back (2). For the next 35 days, the infant rides on the backs of both parents; however, the female rejects them after this time and the male carries the infant until it is around 100 days old (2) (5).

Believed to be one of the rarest Eulemur species, the red-bellied lemur exhibits the common traits of this genus, showing sexual dimorphism and moving quadrupedally through the trees (2). The long, dense fur of the upperparts of both males and females is a deep chestnut-brown colour, which is continued to the males' underparts (2). The females' underparts are creamy-white (2), and the characteristic 'teardrop' patches of white bare skin under the eyes of the males is significantly reduced in the females (2) (5). These 'teardrops' and the dense rich coat help to distinguish this medium-sized lemur from other species of Eulemur that occur in the same areaa. The fur around the males' ears is particularly dense, giving the head a squarish look, which is not as obvious in the females. The tail of both sexes is almost black, and the face and muzzle are dark slate-grey (2).

The range of E. rubriventer extends from northern Madagascar’s Tsaratanana Massif south along the thin strip of east coast rain forest to the Pic d'Ivobe and the Manampatrana River (Irwin et al. 2005), although at one time it ranged further south. It does not occur on the Masoala Peninsula. Ranges from 70-2,400 m.

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

Biogeographic Regions: ethiopian (Native )

Other Geographic Terms: island endemic

Like all lemurs, the red-bellied lemur is endemic to Madagascar, inhabiting the eastern rainforest zone from the Andringitra Massif in the south, to the Tsaratanana Massif in the north. It is thinly distributed and does not occur on the Masoala Peninsula (2) (5).

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).

Range mass: 2 to 3 kg.

Range length: 36 to 54 cm.

Sexual Dimorphism: sexes colored or patterned differently

Habitat and Ecology

Systems

• Terrestrial

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

Habitat Regions: tropical ; terrestrial

Terrestrial Biomes: rainforest

This species inhabits primary and secondary rainforest at medium to high altitudes (2).

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).

Animal Foods: insects

Plant Foods: leaves; seeds, grains, and nuts; fruit; flowers

Primary Diet: herbivore (Folivore , Frugivore )

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

Ecosystem Impact: disperses seeds

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.

Known Predators:

• fossa (Cryptoprocta ferox)
• raptors (Falconiformes)
• humans (Homo sapiens)
• domestic dogs (Canis lupus familiaris)
• domestic cats (Felis silvestris)

Eulemur rubriventer is prey of:
Strigiformes
Homo sapiens
Felis silvestris
Falconiformes
Canis lupus familiaris

This list may not be complete but is based on published studies.

Eulemur rubriventer preys on:
Insecta

This list may not be complete but is based on published studies.

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 ; tactile ; acoustic ; chemical

Perception Channels: visual ; acoustic

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

Range lifespan

Status: wild: 20 to 25 years.

Average lifespan

Status: captivity: 20 years.

Maximum longevity: 20 years (captivity) Observations: One specimen was about 20 years old and still living in captivity (Richard Weigl 2005).

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

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)

Breeding interval: These lemurs are capable of breeding annually.

Breeding season: Mating occurs from May through June with births occuring from September to October.

Range number of offspring: 1 to 2.

Average gestation period: 127 days.

Average weaning age: 5 months.

Average age at sexual or reproductive maturity (female): 2 years.

Average age at sexual or reproductive maturity (male): 2 years.

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

Average birth mass: 85.5 g.

Average gestation period: 130 days.

Average number of offspring: 1.

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 ; 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)

Year Assessed

Assessor/s

Reviewer/s

Justification

History

• 2000
  Vulnerable
• 1996
  Vulnerable
• 1994
  Vulnerable
  (Groombridge 1994)
• 1990
  Vulnerable
  (IUCN 1990)
• 1990
  Vulnerable
  (IUCN 1990)
• 1988
  Indeterminate
  (IUCN Conservation Monitoring Centre 1988)
• 1986
  Indeterminate
  (IUCN Conservation Monitoring Centre 1986)

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.

US Federal List: endangered

CITES: appendix i

IUCN Red List of Threatened Species: vulnerable

Classified as Vulnerable (VU) on the IUCN Red List 2007 (1) and listed on Appendix I of CITES (3).

Population

Population Trend

Major Threats

The formerly extensive range of the red-bellied lemur, along Madagascar's entire eastern rainforest zone, has now been significantly reduced (4), the primary cause being the continued destruction of the eastern rainforest (2). Slash-and-burn agriculture in particular is encroaching on their habitat (1) (2), and illegal activities such as logging and hunting, which are heavy in certain areas, are also a major threat (5).

Conservation Actions

The red-bellied lemur is found in at least nine protected areas in Madagascar, including five National Parks and two Strict Nature Reserves (5). The red-bellied lemur is also protected against international trade under Appendix I of the Convention on International Trade in Endangered Species (CITES) (3). It is fairly rare in captivity, with around 67 red-bellied lemurs currently in captivity worldwide. However, European institutions are keen to continue to breed and manage this threatened Madagascan species (4).

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

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 ; ecotourism ; research and education

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (February 2012)

The Red-bellied Lemur (Eulemur rubriventer) is a medium sized prosimian with a luxuriant chestnut brown coat. This lemur is endemic to eastern Madagascan rainforests and is distinguished by patches of white skin below the eyes, giving rise to a "teardrop" effect, particularly conspicuous in the male.^[3]

The species, first identified in the year 1850, exhibits diurnal behaviour and marked sexual dichromism. The Red-bellied Lemur has been studied extensively since the mid 1980s, primarily in Ranomafana National Park.^[4][5] This lemur species is designated as vulnerable according to the IUCN Red List, due to threats endangering habitats from slash-and-burn agriculture in Madagascar.

Contents 1 Description 2 Range and distribution 3 Behaviour 4 Nomenclature and current events 5 See also 6 References 7 External links

Description

Being sexually dichromatic, the male of the species exhibits a medium-long dense dorsal coat of intense chestnut brown. Ventrally he is lighter and redder in hue, while his tail, muzzle and head are black. For the female, the dorsal area and tail resemble the male, whereas the ventral fur is a contrasting white-cream colour. Facial markings are similar to the male, except that "tear drops" are less exaggerated and spiry thick cheek hairs of the male are absent. Whereas the Eulemur genus relatives may exhibit ear tufts or a furry beard, these features are absent for Eulemur rubriventer, which has thickened fur around its ears, lending a fuller facial appearance.^{[citation needed]}

The adult Red-bellied Lemur has a length of 34 to 40 centimetres (13.4 to 15.7 in) (excluding tail) and a tail length which is almost twenty percent longer than the body itself; that is, body plus tail length may attain a total length of almost one meter. Typical body mass of a mature individual ranges from 1.6 to 2.4 kilograms (3.5 to 5.3 lb).^[6] The male has scent glands atop his head. Lifespans may easily exceed twenty years for both sexes.^{[citation needed]}

Range and distribution

Mid-height view of arboreal habitat in Mantadia National Park

Eulemur rubriventer occurs as far north as the Tsaratanana Massif at an elevation of 2,400 metres (7,900 ft), and thence southerly to the Manampatrana River in a narrow strip of eastern Madagascar rainforest.^[1] In previous eras the range extended further south to the Mananara River. This species is distributed thinly and is restricted only to intact rainforest; it does not occur at all on the Masolala Peninsula.^{[citation needed]}

The Red-bellied Lemur is sympatric with four other Eulemur species: in the extreme north of its range, the White-headed LE. albifrons; at mid-range, the Common Brown LE. fulvus; and in its southern range, the Red-fronted Brown LE. rufus and the Gray-headed LE. cinereiceps. E. rubriventer is however easily distinguished from these relatives by the male's distinctive white eye "tear drops" and the rich darkness of the fur of both sexes. A distinction of appearance occurs within E. rubriventer in that northern range males (e.g. Mantadia National Park north) have a more distinctive reddish belly than the southern range counterparts, as in Ranomafana National Park.^[7]

The forest type within the Red-bellied Lemur's range is characterized by dense evergreen vegetation, with a canopy of 25 to 35 metres (82 to 115 ft). Typical canopy species include Dalbergia sp., Diospyros sp., Ocotea sp., Symphonia sp., and Tambourissa sp.; emergents of Canarium sp., Albizia sp., and Brochoneura acuminata are also present. The eastern lowland forests also have a rich diversity of Pandanus sp., bamboo, and epiphytic orchid species.^{[citation needed]}

Behaviour

The Red-bellied Lemur aggregates in monogamous groups ranging from two to ten individuals. It is one of the few lemurs to be recognized as cathemeral, having both diurnal and nocturnal activity patterns. The home range is estimated to be 25 to 35 acres (10 to 14 ha) with a typical density of five animals per acre. Groups are typically cohesive as they move within their home range, foraging on over thirty species of plants. Considered by some to be a frugivore, it also feeds on leaves, nectar and flowers of many plant species; this lemur is believed to be a useful and efficient seed disperser.^{[citation needed]}

Lower story of Montadia rainforest habitat at a clearing

A typical and maximum frequency of births is one offspring per female per year, with initial year infant mortality at about fifty percent. Births normally occur in October and November (early summer in this southern hemisphere habitat). The young use their prehensile instincts in order to attach to the mother and father alternately for the first 33 to 37 days of life. At this point the mother often refuses further transport services, whilst the father may continue to provide such for another nine weeks.^{[citation needed]}

Nomenclature and current events

There are various Malagasy tribal names for the Red-bellied Lemur including tongo, tagona, halomena, kirioka and soamiera. In the French scientific literature (Madagascar’s second official language is French, due to prior colonisation by France) the species is called Lémur à ventre rouge.^{[citation needed]}

Modern feeding habits have expanded the species' diet to the introduced "Chinese" (actually Brazilian) guava (Psidium littorale). Groups of the Red-bellied Lemur have become somewhat habituated to humans along certain trail areas in Ramomafana National Park (around Blue Vue) starting in May and June, and much rarer in some lower trail areas of Montadia National Park starting in April. In both instances the species exhibits a tame behaviour to approaching humans who are silent and walk softly. The animals will descend from the trees to within two or three meters staring back at the humans with equal curiosity allowing themselves to be photographed as they cling to vertical trunks of saplings, and occasionally engaging in a terrestrial scamper.^{[citation needed]}

Eulemur rubriventer occurs in five national parks and seven special reserves in eastern Madagascar, but is classified as Vulnerable (IUCN Red List) due to ongoing habitat reduction from slash-and-burn farming, illegal logging and even hunting. The species is the subject of current study in its natural habitat as well as in captivity in research centers such as the Duke Lemur Center.^{[citation needed]}

See also

• Madagascar lowland forests
• Tropical moist broadleaf forest

References

1. ^ ^{a b} Groves, C. (2005). Wilson, D. E.; Reeder, D. M. eds. Mammal Species of the World (3rd ed.). Baltimore: Johns Hopkins University Press. pp. 116. OCLC 62265494. ISBN 0-801-88221-4. http://www.bucknell.edu/msw3/browse.asp?id=12100045. 
2. ^ Andrainarivo, C., Andriaholinirina, V. N., Feistner, A., Felix, T., Ganzhorn, J., Garbutt, N., Golden, C., Konstant, B., Louis Jr., E., Meyers, D., Mittermeier, R. A., Perieras, A., Princee, F., Rabarivola, J. C., Rakotosamimanana, B., Rasamimanana, H., Ratsimbazafy, J., Raveloarinoro, G., Razafimanantsoa, A., Rumpler, Y., Schwitzer, C., Thalmann, U., Wilmé, L. & Wright, P. (2008). Eulemur rubriventer. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 07 October 2008.
3. ^ Russell Mittermeier et al., Lemurs of Madagsacar, Conservation Press (2006)
4. ^ B. Meier, Preliminary report of a field study of Lemur rubriventer and Hapalemar simus (nov. species) in Ranomafana-Itandiana (1986-87) Report to Ministry of Scientific Research, 312 Faritany Fianaransoa, Antananarivo, Madagascar
5. ^ C. Dague and J.J. Peter, Observations sur le Lemur ruriventer dans son milieu naturel, In: L. Rakotovao, L’Equilibre des Ecosystems Forestiers a Madagascar: Actes d’un seminaire international IUCN, Gland Switz and Cambridge (1988)
6. ^ K.E. Glander et al., Morphometrics and testicle size of rainforest lemur species from southeastern Madagascar, Journal of Human Evolution 22:1-17 (1992)
7. ^ Lumina Technologies, Observations, behavior and marking of Eulemur rubriventer, Letter report to the Ministry of Scientific Research. Antanarivo, Madagascar, April 19, 2006