Latest / What’s the Story: The Sri Lanka Podcast / Sylvan Swingers I Scaling The Monkeys & Lorises of Sri Lanka
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- Sylvan Swingers I Scaling The Monkeys & Lorises of Sri Lanka Die-hard individualists fail to fault the remarkable variation found within Sri Lanka’s different species of monkeys and loris. So what are their arboreal secrets? Nearly seven million monkeys leap about Sri Lanka’s trees, the vast majority of them Toque Macaques. To these can be added a handful of lorises, their ancient and more wet-nosed primate relatives. These much-overlooked mammals of beguiling rarity and beauty have a talent for invisibility that outstrips even that of Tolkien’s Frodo when wearing The Ring, their visibility not aided by the serious existential threat they face, with numbers of the combined loris species barely rising much above 100,000. With over a third of the country still covered by forests and over 800 trees and shrubs to choose from, the island is a tree hugger’s Shangri-la, and on first sight, it would seem quite logical to assume that Sri Lanka was overrun with monkeys of many species. But in fact, the reverse is true. Quality trumps quantity. Just three variants are found on the island: The Hanuman Langur, the Purple-Faced Langur, and the Toque Macaque. The Hanuman Langur The Hanuman langur, also called the Tufted Grey langur, is one of three Semnopithecus priam variants, all of which are found in India. Still, only Semnopithecus priam thersites lives in Sri Lanka. Various theories – conflicting, convoluted and essentially unprovable – have been put forward to account for why the Sri Lankan subspecies, thersites, differs from those found in India. However, the differences would tax Sir Arthur Conan Doyle's deductive powers. Even so, patriotic toxicologists are pressing the case for the Sri Lankan variant to be declared a separate endemic species in its own right. As the debate on this rumbles on, the langur in question gets on with its life blamelessly – and relatively unthreatened by the millstones of modern life. It was named rather eccentrically after Thersites, a bow-legged antihero from Homer’s Trojan Wars, who Plato later promoted as the man best suited for the afterlife. This was a doubtful honour to bestow on one of Sri Lanka’s elite mammals. Up to 60 inches long head to tail, with a weight that can reach close to 15 kilos, its black face is framed by a wispy white beard that runs from the forehead to the chin. It is a light grey in colour and lives as readily in dry forests as in urban areas – showing a strong preference for ancient cultural sites, as evidenced by its dwellings in places such as Polonnaruwa, Dambulla, Anuradhapura, and Sigiriya. Once settled, they tend to stay put, having little of the gypsy tendency within them. Eagerly vegetarian, they live in troops of up to 50 members, the larger ones being curiously non-sexist, with leadership shared by a male-female pair. Langur monkeys come with all the complexities of a relatively capacious family – and they live in groups within which strict social hierarchies are observed. Quite how many species belong to the Langur family is a subject of modest debate amongst mammalian taxonomists, but at the last count there were eight. Or seven, depending, stretching from the Himalayas to Sri Lanka. The Purple-Faced Langur The Hanuman langur shares the closest of all possible evolutionary relationships with the island’s second monkey species, the purple-faced langur, so much so, in fact, that they have even been known to mate. This is the rarer of the island’s two langur species, its endemic status free of any debate or argument. It lives mainly in dense forests but is now threatened by habitat loss, which has noticeably reduced its numbers. Vegetarian, with a tendency to eat leaves rather than other foods, it is shy and slightly smaller than the Hanuman langur. Still, it can be told apart by its darker colouring, the black-brown fur of its body contrasting with the mop of wispy white fur that surrounds its face and sits atop its head. Despite, or perhaps because of being one step away from being critically endangered, the purple-faced langur has settled into its different island environments like a hand in a glove and evolved into a variety of subspecies. The Southern lowland wet zone purple-faced langur stands out for its more varied markings – a black upper torso and lavish white whiskers. Occasionally, all-white versions are spotted. The Western purple-faced langur - also confusingly named the north lowland wet zone purple-faced langur is the smallest of the lot, its fur a dark greyish brown. The Dryzone purple-faced langur, in contrast, is the largest version - with arresting white cheeks and an exceptionally long tail. The Montane purple-faced langur, sometimes called the Bear Monkey, comes with extra shaggy fur, all the better to keep it warm on the higher mountains on which it prefers to live. Excited taxologists from Jaffna have also called for the recognition of a fifth subspecies - vetulus harti. Although there are no reliable recorded sightings of it as a living mammal, its pelts have been found around Jaffna and Vavuniya – strikingly yellow gold. The Toque Macaque The island’s third monkey species – the Toque Macaque is to be found almost everywhere, living its best life, undeterred by much of what growing urbanisation can throw at it. Their appearance is one of the most remarkable things about them. With white undersides, golden brown fur on their backs and a car crash of an almost orange coiffure, they look as if they have got lost in a cheap tanning salon or a Trump rally. Pink faces peer out below recherché hairstyles, giving substance to their name - “toque,” the brimless cap that is their bob. They can weigh up to 12 pounds and have a head-to-tail length of almost a metre. Whilst they have been known to live for thirty-five years, most die within five, victims of infant mortality or fights within troops for dominance. They are accomplished scavengers; their vegetarian fancies are best satisfied on fruit. Their capacious cheek pouches are specially adapted to store food for later consumption, a technical refinement that helps them steal, store, and run with their pilfered bounty. As dexterous at leaping through trees as at capering across the ground, or even swimming, they move in self-protective groups and sleep huddled together every night in a different place, like chastened celebrities or terrorists. They are easy to spot because they are active during daylight hours, appearing in groups of 20, led by an alpha male, with half the group composed of infants or juveniles. Young adult males wisely leave the group upon attaining maturity, for fear of being chased out. But they also have a reputation for being very matey with other species – the family dog, for example. And they talk to one another. Naturalists have recorded over thirty different sounds, each conveying a particular meaning. Common though they are, they have not prevented them from evolving into three separate endemic variants, their differences indistinct to all but mothers and fond scientists best able to decipher the marginal differences presented in the patterns and colours on their heads. The Pale-Fronted or Dusky Toque Macaque sticks to the wet zones in the southwest. The Common Toque Macaque favours the dry-zone areas of the north and east. The Highland Toque Macaque favours the hilly centre of the island. The Loris Whilst only the most luckless traveller would fail to spot at least a couple of Sri Lanka’s various monkeys, only the most fortunate would see any of its lorises. And that a long, long after they might have spotted you. Constructed with small bodies and lean, outsized limbs, their round heads bear a set of disproportionately immense panda eyes set within circles of black fur that give them the look of learned, albeit eccentric, professors of philosophy, peering at you through Tortoiseshell spectacles, like happy Gollums. It is no surprise, therefore, to learn that they have large brains for so tiny an animal. Their ears are almost invisible, but should they grasp you with their fingers or toes, you would immediately feel the resolute strength that comes from a creature that lives almost entirely on tree branches. Placing one hand before another, they move along boughs with great deliberation, and often upside down- but unlike monkeys, neither leap nor jump. How they communicate with one another remains one of many scientific mysteries surrounding the species. Still, they are known to be inordinately social, wrestling for the sheer fun of it and sleeping together in tightly packed groups within tree branches, specially built tree nests, or tree holes. And whilst they particularly like to eat insects – especially ants – they are also eager consumers of eggs, berries, leaves, buds, and unlucky lizards. They live for around 15 to 18 years. And they live an upside-down life, sleeping by day, and out and about by night. This makes them almost impossible to see, a task made all the harder given their diminutive size, extreme shyness, rapidly diminishing numbers, and preference for calling home the tops of trees. Yet amongst Sri Lankans, sighting one is something of a mixed blessing. In island folklore, the loris has a cry that can call devils to a house, so it is often regarded with a certain amount of dread. To wake up and find one staring at you is considered to be one of the worst possible omens; should it then reach out and touch you, your body will respond by becoming skin and bones. Of the world’s eleven loris subspecies firmly agreed upon and recorded, two are based in Sri Lanka, one grey, one red. The Grey Slender Loris The grey slender loris (Loris lydekkerianus) is something of a mater, being, it is thought, even more promiscuous than other loris species. Males eagerly beseech and badger the females for a pot of love making, several to one, twice yearly in April and December - though the female restricts herself to one birth period a year – often of twins. Despite their sexual enthusiasm, they are noted for having one of the lowest reproduction rates of small mammals – no great help for a species that hovers between near threatened and endangered on the Red List. Survival rates are not much helped either by their reputation for being cute pets, beneficial ingredients in love potions, and core components in village medicine to alleviate eye infections – and, bizarrely, leprosy. But then again, why not: great discoveries are never made by modest expectations. Yet by far the gravest threat they face is habitat loss. Being committed tree dwellers, the fragmentation of forests and ranges impacts them with unrelenting fury. The colour of grey lorises varies greatly – from grey to reddish grey, often with a dark strip running from head to tail, and the darker fur around their eyes giving them a Sophia Loren gaze. Thus far, thus simple. But not for long, for the species has evolved with dizzying complexity. Although the grey loris has made its home in both India and Sri Lanka, at the Sri Lankan end, it has evolved into two subspecies. The first of these, the Northern Ceylonese slender loris, Loris lydekkerianus nordicus, lives in the dry northern and eastern forest regions of the island. A slow-moving midget, its body measures barely 200 mm and weighs little more than 250 grams. With a logic explicable only to other and, quite possibly, mad scientists, the Highland slender loris, Loris lydekkerianus grandis, despite having “grandis” in its name, weighs in at much less – barely 100 grams. It can be distinguished by its shorter ears, its face – more like a love heart than that of the Northern Ceylonese slender loris – and hair that, at its very root, is more black than white. It keeps, as its name implies, to the highland areas of Sri Lanka. The Red Slender Loris The second main loris species – the red loris, more commonly known as the Ceylon Red Slender Loris (or Loris tardigradus)- has no family connections in India; it is rooted firmly and entirely in Sri Lanka. Rare though it is, it has nevertheless been busy evolving into three distinct varieties. The first of these, Loris tardigradus tardigradus, keeps itself to the wet, lowland forests in southwest Sri Lanka. It weighs up to 172 grams and has a body that extends to just over 17 centimetres. It has dense reddish-brown fur and the classic slender hands and legs of all its species, an evolutionary peculiarity that enables it to climb easily through treetops to gather the fruits, berries, and leaves on which it feasts. By day, they sleep in leaf-covered tree holes, a habit that must help explain their relatively long lifespan (15-18 years). Its mothers are not to be crossed and have the intriguing habit of coating their offspring in allergenic saliva, a toxin that repels most predators. Loris tardigradus grandis is found in slightly hilly areas – up to about 1000 meters. As its Latin name implies, this loris subspecies is larger than most other lorises. It can also be singled out in different ways. For example, its limbs are more heavily furred and, according to its less charitable observers, it presents a less delicate appearance than its cousins. It can weigh up to 227 grams and has been known to extend 256 mm from head to body. Beyond this dwells the rarest of the three - Loris tardigradus nycticeboides, the mountain loris, noticeable for its shorter limbs and thicker fur and almost only seen in the high cloud forests of Horton Plains. It is locally known as kada papa, or "baby of the forest". There, in 1937, a certain Mr A. C. Tutein-Nolthenius, who had spent twenty years looking for the species, discovered a mother with two offspring. They were to die in captivity. The last recorded sighting was in 2002, also on Horton Plains, when a researcher got but a glimpse of a secretive pair. Arguments still rage over the possibility of a further subspecies – the Loris Tardigradus Nordicus. Discovered as far back as 1932 in the Knuckles Range, it subsequently appeared in areas as diverse as Anuradhapura, Polonnaruwa, Kurunegala, Puttalam, Trincomalee, and Matale. It is said to have a very distinctive facial stripe and a greyish coat of thin fur, and it can weigh 293 grams. Scientists are divided as to whether this possible variant belongs best to the red or grey loris family. Three monkeys, two lorises, and a not-to-be-sniffed-at assortment of species variation within most of the creatures in no way really demonstrate the daily delight of seeing any one of them on our daily commute to the office or temple. Almost anywhere, even in the most sophisticated parts of Colombo, where the beautiful people dine, divorce and dance, monkeys will be seen – though for lorises, you need to be good, intelligent, and lucky. Even so, the failure to spot one after a hard night's trekking is reward enough, reminding you, with wise and mindful care, that nature is not here for our benefit, nor should it be on call as an all-night drive-through McDonald's. That was a production written and recorded by David Swarbrick at The Ceylon Press, based in the jungle north of Kandy, at The Flame Tree Estate & Hotel, and set up to tell the story of Sri Lanka.