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Saturday 11 July 2015

New Arrival: White-Belted Black and White Ruffed Lemur


Now on show at Wildplace is a new addition to their lemur collection, a young paid of the Northern or White-Belted Black and White Ruffed Lemur, Varecia variagata subcincta. This is one of three subspecies of V.variagata, plus the only other species of Varecia, the Red Ruffed Lemur V.rubra. Bristol Zoo has two V.rubra that are hand tame and are used in their daily animal displays, but these are non-breeding animals. The Wildplace pair will hopefully breed in the future, as they are a young pair.


Varecia lemurs are among the largest living lemurs, reaching over 1m nose to tip of tail and a weight of up to 4kg. Today they are exceeded only by the Indri, which is over twice that weight. Prior to the mass extinction of the megafauna of Madagascar after humans arrived around 2000 years ago there were many much larger ones, with the various koala-lemurs Megaladapis spp reaching 50kg or more and the gigantic Archaeindris reaching an estimated 250kg – about the same as a silverback gorilla!

As with all lemurs, V.variagata subcincta is currently listed as Critically Endangered. They are major targets for illegal, but unenforced, bushmeat hunting, and habitat destruction from slash and burn cultivation, illegal logging, and mining activities. As animals that are restricted to primary rainforest, they need large areas to provide sufficient fruit (their main diet). Unfortunately, their favourite food trees are also the ones preferentially logged, adding to the threat.  Typical home ranges measured are around 90 hectares, with population densities depending on hunting pressure and habitat quality ranging from 0.25 – 43 animals per km2

The geographic range of the various Varecia species is today restricted to lowland to mid-altitude rainforest in the north eastern part of the island. V.variagata subcincta is today found north of the Anove river. In the 1930’s they were introduced to the island Nosy Mangabe, where they still suvive.
Varecia society seems to be quite variable. They are found either in pairs or small family groups usually, but they may also exhibit a fission-fusion type of society with individuals moving between different groups. They are quite vocal, and their large screaming territorial calls, especially when the whole group joins in, will carry for miles across the forest.

 Unlike other lemurs, they produce litters of 2-3 (rarely up to 6) young at a time, and leave them in a special nest until the young are around a week old. After that time the female moves the young by carrying them in her mouth, and leaves them parked on a branch near where she forages. By the time they are three or four weeks old they are mobile and can follow her around. Infant mortality is high, and in practice females seem to mostly succeed in raising on average one young every other year at best.

As well as human hunting, ruffed lemurs face a variety of natural predators. Although they spend most of their time in the canopy, they are vulnerable to mainly terrestrial predators such as the fossa and ring-tailed mongoose, large snakes, and various raptors such as Henst’s Goshawk. Various recently extinct raptors, notably the Malagasy Crowned Eagle Stephanoaetus mahery were probably also lemur specialist predators.

For more on these and other lemurs, check out the website of the Duke Lemur Center: http://lemur.duke.edu/. For the work that Wildplace and Bristol Zoo are involved in check out the AEECL website (link at right)


(Photos are mine)

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