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Wednesday, 28 December 2016

14-10-2015 VALENCIA BIOPARC - RING TAILED LEMUR (Lemur catta)


The ring-tailed lemur (Lemur catta) is a medium- to larger-sized strepsirrhine (wet-nosed) primate, and the most internationally-recognized lemur species, owing to its long, black-and-white, ringed tail. It belongs to Lemuridae, one of five lemur families, and is the only member of the Lemur genus. Like all lemurs, it is endemic to the island of Madagascar, where it is endangered. Known locally in Malagasy as maky ([makʲ] ⓘ, spelled maki in French) or hira, it ranges from gallery forests to spiny scrub in the southern regions of the island. It is omnivorous, as well as the most adapted to living terrestrially of the extant lemurs.

The ring-tailed lemur is highly social, living in groups of up to 30 individuals. It is also a female-dominant species, a commonality among lemurs. To keep warm and reaffirm social bonds, groups will huddle together. Mutual grooming is another vital aspect of lemur socialization (as with all primates), reaffirming social and familial connections, while also helping rid each other of any potential insects. Ring-tailed lemurs are strictly diurnal, being active exclusively during daylight hours. Due to this lifestyle, they also sunbathe; the lemurs can be observed sitting upright on their tails, exposing their soft, white belly fur towards the sun. They will often also have their palms open and eyes gently closed. Like other lemurs, this species relies strongly on their sense of smell, and territorial marking, with scent glands, provides communication signals throughout a group’s home range. The glands are located near the eyes, as well as near the anus. The males perform a unique scent-marking behavior called spur-marking, and will participate in stink fights by dousing their tails with their pheromones and “wafting” it at opponents. Additionally, lemurs of both sexes will scent-mark trees, logs, rocks or other objects by simply rubbing their faces and bodies onto it, not unlike a domestic cat.


As one of the most vocal primates, the ring-tailed lemur uses numerous vocalizations, including calling for group cohesion and predator alarm calls. Experiments have shown that the ring-tailed lemur, despite the lack of a large brain (relative to simiiform primates), can organize sequences, understand basic arithmetic operations, and preferentially select tools based on functional qualities.


Despite adapting to and breeding easily under captive care (and being the most popular species of lemur in zoos worldwide, with more than 2,000 captive-raised individuals), the wild population of ring-tailed lemur is listed as endangered by the IUCN Red List, due to habitat destruction, local hunting for bushmeat and the exotic pet trade. As of early 2017, the population in the wild is believed to have crashed to as low as 2,000 individuals due to these reasons, making them far more critically endangered. Local Malagasy farmers and logging industries frequently make use of slash and burn deforestation techniques, with smoke being visible on the horizon on most days in Madagascar, in an effort to accommodate livestock and to cultivate larger fields of crops.


Endemic to southern and southwestern Madagascar, the ring-tailed lemur ranges further into highland areas than other lemurs. It inhabits deciduous forests, dry scrub, montane humid forests, and gallery forests (forests along riverbanks). It strongly favors gallery forests, but such forests have now been cleared from much of Madagascar in order to create pasture for livestock. Depending on location, temperatures within its geographic range can vary from −12 °C (10 °F)[24] at Andringitra Massif to 48 °C (118 °F) in the spiny forests of Beza Mahafaly Special Reserve.

This species is found as far east as Tôlanaro, inland towards the mountains of Andringitra on the southeastern plateau, among the spiny forests of the southern part of the island, and north along the west coast to the town of Belo sur Mer. Historically, the northern limits of its range in the west extended to the Morondava River near Morondava. It can still be found in Kirindy Mitea National Park, just south of Morondava, though at very low densities. It does not occur in Kirindy Forest Reserve, north of Morondava. Its distribution throughout the rest of its range is very spotty, with population densities varying widely.

The ring-tailed lemur can be easily seen in five national parks in Madagascar: Andohahela National Park, Andringitra National Park, Isalo National Park, Tsimanampetsotse National Park, and Zombitse-Vohibasia National Park. It can also be found in Beza-Mahafaly Special Reserve, Kalambatritra Special Reserve, Pic d'Ivohibe Special Reserve, Amboasary Sud, Berenty Private Reserve, Anja Community Reserve, and marginally at Kirindy Mitea National Park. Unprotected forests that the species has been reported in include Ankoba, Ankodida, Anjatsikolo, Anbatotsilongolongo, Mahazoarivo, Masiabiby, and Mikea.

Within the protected regions it is known to inhabit, the ring-tailed lemur is sympatric (shares its range) with as many as 24 species of lemur, covering every living genus except Allocebus, Indri, and Varecia. Historically, the species used to be sympatric with the critically endangered southern black-and-white ruffed lemur (Varecia variegata editorum), which was once found at Andringitra National Park; however, no sightings of the ruffed lemur have been reported in recent years.


The ring-tailed lemur is an opportunistic omnivore primarily eating fruits and leaves, particularly those of the tamarind tree (Tamarindus indica), known natively as kily. When available, tamarind makes up as much as 50% of the diet, especially during the dry, winter season. The ring-tailed lemur eats from as many as three dozen different plant species, and its diet includes flowers, herbs, bark and sap. It has been observed eating decayed wood, earth, spider webs, insect cocoons, arthropods (spiders, caterpillars, cicadas and grasshoppers) and small vertebrates (birds and chameleons). During the dry season it becomes increasingly opportunistic.


Troops are classified as multi-male groups, with a matriline as the core group. As with most lemurs, females socially dominate males in all circumstances, including feeding priority. Dominance is enforced by lunging, chasing, cuffing, grabbing and biting. Young females do not always inherit their mother's rank and young males leave the troop between three and five years of age. Both sexes have separate dominance hierarchies; females have a distinct hierarchy while male rank is correlated with age. Each troop has one to three central, high-ranking adult males who interact with females more than other group males and lead the troop procession with high-ranking females. Recently transferred males, old males or young adult males that have not yet left their natal group are often lower ranking. Staying at the periphery of the group they tend to be marginalized from group activity.

A group of three ring-tailed lemurs rest in the sun, with two sitting upright, facing the sun, with their arms to their sides.
The ring-tailed lemur will sit facing the sun to warm itself in the mornings.
For males, social structure changes can be seasonal. During the six-month period between December and May a few males migrate between groups. Established males transfer on average every 3.5 years, although young males may transfer approximately every 1.4 years. Group fission occurs when groups get too large and resources become scarce.

In the mornings the ring-tailed lemur sunbathes to warm itself. It faces the sun sitting in what is frequently described as a "sun-worshipping" posture or lotus position. However, it sits with its legs extended outward, not cross-legged, and will often support itself on nearby branches. Sunning is often a group activity, particularly during the cold mornings. At night, troops will split into sleeping parties huddling closely together to keep warm.

Despite being quadrupedal the ring-tailed lemur can rear up and balance on its hind legs, usually for aggressive displays. When threatened the ring-tailed lemur may jump in the air and strike out with its short nails and sharp upper canine teeth in a behaviour termed jump fighting. This is extremely rare outside of the breeding season when tensions are high and competition for mates is intense. Other aggressive behaviours include a threat-stare, used to intimidate or start a fight, and a submissive gesture known as pulled-back lips.

Border disputes with rival troops occur occasionally and it is the dominant female's responsibility to defend the troop's home range. Agonistic encounters include staring, lunging approaches and occasional physical aggression, and conclude with troop members retreating toward the center of the home range.

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