Long Tail Macaque

For more about Long Tailed Macaques, check out the Letters From the Field blog,

Why Are Millions of Monkeys Coming Out of Southeast Asia?

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What’s in a name? In the case of this month’s featured primate, a name can say a lot! From ‘Long Tail Macaque’ to ‘Crab Eating Macaque’; from Macaca fascicularis to ‘Cynomologus monkey’; from ‘Philippine monkey’ to ‘Kaku’; each provides a little insight into this primate’s unique character, appearance, and relationship to the world around it.

Seen together, the range of names used to refer to this primate reflects the sheer geographic and physical diversity of the species.  The Long Tail Macaque has among the widest native range of any monkey, with native populations found throughout Southeast Asia including Indonesia, the Philippines, Brunei, Burma, Cambodia, Laos, Malaysia, the Philippines, Thailand, and Vietnam. Able to thrive in a range of primary and secondary rainforests, rainforests of nipa palm and mangrove, and in and around human settlements, the Long Tail Macaque has adapted to a range of environments and as a result displays tremendous diversity; ten sub-species of this macaque have been identified based on variations in social and physical differences such as color, mating customs and group size.

Some names reflect physical characteristics. ‘Long Tail Macaque’ recalls this primate’s uniquely long tail, which often extends to a length greater than the individual’s body from head to rump. Spending most of their time in the trees and well-adapted to climbing, these incredibly long tails help the macaques balance when leaping between branches to a distance of up to 5 meters (16.4 feet!).  Long Tail Macaques also sleep in trees, with each social group sharing one tree and individuals huddling together to avoid the cold.

The scientific name Macaca fascicularis can be traced to a combination of the West African word for monkey, “kaku” (macaca), and the Latin word for “a small band” (fascicularis). With pinkish-brown faces and fur that sweeps back over their foreheads, the reference to a “small band” indicates the crest of swept-up hair found on the crown of their heads. Infants are born with black fur that turns into a light brown or grayish to brown color after about three months, depending on sub-species. This youthful black coat may serve to display the helpless status of the infant, causing the older individuals in the group to treat them with the utmost care and protect them in times of distress.

The name ‘Crab Eating Monkey’ may be misleading; rather than indicating a preference for crab meat, it should point toward the varied diet that these macaques enjoy- a diet which occasionally includes marine crustaceans and shellfish (their well developed swimming skills not only enable them to sample aquatic animals but also enable them to more easily escape predators such as pythons, monitor lizards, raptors and large cats). Fruits and seeds actually compose 60-90% of their diet, with leaves, flowers, roots, bark, small vertebrates, invertebrates and bird eggs also consumed from time to time. Long Tail Macaques have cheek pouches, which they use for storage and transportation during the foraging process.

In Indonesia, Long Tail Macaques are often referred to as “kera”, perhaps because of the alarm calls they cry out when in danger- high-pitched calls that sound much like “krra!” Communication is always useful in times of danger, but is not limited to emergencies; in fact, Long Tail Macaques have a well-developed social structure that is highly dependent on interpersonal communication. In the wild they can be found in groups ranging from 5-60 individuals, with an average group size of 30. Each group has a few males and as many as 2-3 times as many females. Males move in and out of groups several times throughout their lives while females remain in the same group. Like other macaque species, both individuals and groups have a social rank that can persist throughout generations, and grooming is an important part of forming social bonds and finding mates. When they aren’t foraging, older long-tailed macaques can be seen grooming one another or resting while youngsters play.

In laboratory settings the long-tailed macaque is known as the Cynomologus monkey. The growing importance of this name reflects the growing use of Long Tail Macaques in research settings; they recently surpassed Rhesus macaques to become the most commonly imported primate in the United States. Between January and June 2008 the United States imported 12,564 primates, 11,947 (95%) of whom were Long Tail Macaques, all of whom are intended spend their lives as research subjects.

The increasing number of imported Long Tail Macaques is a disturbing figure that indicates a growing threat not only to the well being of individuals but also to the survival of the species as a whole. Currently listed as a Near Threatened species, these primates are soon likely to qualify for a threatened category on the IUCN Red List of Threatened Species.

Many of these macaques have been illegally caught in the wild and trafficked by way of China. A recent video released on the BUAV website depicts footage of the illegal trapping of wild Long Tail Macaques inside a Cambodian nature reserve and goes on to show some of the awful conditions these monkeys must endure inside a breeding farm. Scared out of the trees they call home, stuffed in bags, locked in bare cages, transported across the ocean and forced to live lives of pain and suffering as research subjects is a far cry from the lifestyle of foraging and play these macaques would have enjoyed.

Written by Molly McDonough for our Winter/Spring 2009 "Staying Connected" Newsletter         

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of wild long tail macaques

courtesy of ARKive.org: