Fast Fact Attack: Endangered Species No. 96 – The Black and White Ruffed Lemur

“It’s a matter of taking the side of the weak against the strong, something the best people have always done.”
Harriet Beecher Stowe

The name lemur is taken from the Latin word lemurēs.  Lemurēs were “shades or spirits of the restless or malignant dead and haunters of the night”.  Lemurs were probably so named because of their appearance and nocturnal habits.

Clearly this legend no longer protects this rare and critically endangered primate.  The black and white ruffed lemur, being quite large, is now viewed more as a tangible, edible commodity than an elusive, mythical spectre. Sadly, its distinctive black and white markings, its size and its daylight activity, make it, as you would imagine, hard to miss when sitting in the trees;  it is now heavily hunted. Black and white ruffed lemur meat is also expensive and much sought after.

But, there is an even broader threat to the existence of the black and white ruffed lemurs – extensive deforestation has left them with very little space to find food and shelter.  Their forests have been cleared by slash-and-burn agriculture, logging and mining, greatly endangering the species.

With the capacity to produce up to six babies at a time, it would be quite reasonable to assume the species could replenish any losses quite quickly, but unfortunately there is a very high infant mortality rate.  The mothers build special nests for their young whilst they await their arrival, well-hidden in trees and ten to twenty metres above the ground.   Quite unique, but, sadly many babies fall from the nests and die before reaching a few weeks old, and only around thirty-five per cent survive longer than three months.  The ones that do survive don’t have enough trees to live in or live off.  They rely heavily upon fruit in their diet and the trees they favour are disappearing at an alarming rate.

Black and white lemurs are important pollinators. Though they may well be unaware of this, when feeding on the nectar of the traveller’s palm, they automatically transfer pollen between the flowers, thus ensuring the ongoing success of the palm trees.

These lemurs, together with the red ruffed lemurs, are one of the largest of all extant lemurs.  Both male and female are the same in appearance and size, and can grow up to four feet in length and weigh up to ten or twelve pounds.  They both have soft, thick fur with black and white markings, a ruff of long white fur around the ears and neck, and under the chin.

Black and white ruffed lemurs have thick, furry tails. These are longer than the body and are used for balance.  They move through the trees and on the ground in quadrupedal fashion.

These adorable primates are arboreal and crepuscular (active mainly in the early morning and late afternoon).  They normally live in groups consisting of two to five individuals (though larger groups do occur) and communicate using a range of raucous vocalisations, second only to the howler monkey in volume.  The most used calls are predator alarm calls, locator calls and mating calls.  Choruses can be heard throughout the day but are stepped up during periods of high activity, making these lemurs very easy to find.  Lemurs also have an enlarged sensory organ to help read smells, pheromones, and other chemical signals.

A peculiar and comical trait  of  lemurs is their penchant for relaxing while facing the sun.  The black and white ruffed lemur is no exception.  Arms are usually outstretched as they soak up the sun, as if hoping for the perfect tan.

The females in the troop are the dominant members and can, as such, choose their own mates. They also get first dibs on the food. The black and white ruffed lemurs were thought to be monogamous and bond for life, but this has since been disputed. They are now thought to be polygamous.

Breeding is seasonal (between May and July) and the gestation period running up to the birth is normally three months.  Prior to the birth, the females will build a nest for the imminent arrivals. The nests will made of twigs and leaves and lined with the female’s fur, which she will have pulled out herself.  They are the only true lemurs to build nests. Births of six infants have been recorded, and the females do have six mammary glands to support such large births, but the usual number is between two and four.  The new babies will stay in the nest until they are about two or three weeks old when they will start to move around after the mother.  Whilst very young and still in the nest, mothers carry the young in their mouths and ‘park’ them in safe spots while they forage for food.  At about five weeks the infants will start climbing trees.  Males are also known to take part in the parenting of the young.

The black-and-white ruffed lemur (Varecia variegata) is the more endangered of the two species of ruffed lemurs, both of which are endemic to the island of Madagascar. The other being the red ruffed lemur (varecia rubra).

Three subspecies of black and white ruffed lemur are recognised, the southern ruffed lemur (Varecia variegata editorum), the white-belted ruffed lemur (Varecia variegata subcincta) and the black-and-white ruffed lemur (Varecia variegata variegata), all of which are classified as Critically Endangered by the IUCN. [1]

Natural Habitat
Primary and secondary lowland and mid-altitude rainforest.
Where What they eat
Lemurs are mainly frugivorous but nectar, flowers, leaves and seeds are also eaten.
Threats
Habitat loss due to illegal logging, illegal mining and slash-and-burn agriculture techniques. The black and white ruffed lemur are also heavily hunted for their meat. Natural predators include birds of prey, mongooses, fossa and boa constrictors.
Status: Critically Endangered
The black and white ruffed lemur (Varecia variegata) is listed on the IUCN Red List of Threatened Species as Critically Endangered. In fact, all three of the recognised subspecies are classified as Critically Endangered by the IUCN.  The species is also listed on CITES Appendix I.  Exact population numbers are unknown, but are thought to be declining rapidly.
If this species is to survive in the wild, the forest reserves it inhabits need to be better protected. Although they are part of various successful captive breeding programs, which have in turn reintroduced the black and white lemur back to the wild, these programs have ultimately failed the black and white ruffed lemurs because of the lack of safe, natural habitat available for the animals on arrival in Madagascar.

The following videos all show animals in captivity, the first two being shot at  Sacramento Zoo  where this species is bred to “educate the public on how they can help these and other animals in the wild.”  I have not been able to obtain any footage of black and white lemurs in the wild.

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