Javan Slow Loris

The Berlin Zoologischer Garten has one of the largest and most extensive night houses that I’ve ever seen. Not content to simply fill a room with thousands of flitting bats, they display an exciting array of interesting nocturnal animals from all over the world, terrariums filled with aardvarks, spring hares, blind moles, gerbils and, most impressively, a Javan Slow Loris. The Javan Slow Loris is a small arboreal mammal, around 600 grams in weight, with long brown and cream coloured fur, which form up in a distinctive forked band running down its back. It gets its name from its slow, deliberate movements, lifting itself from branch to branch at an almost leisurely pace, which displays the Loris’s strong grip and unique muscle structure that allows it to hang from branches with little effort (similar to the locking grip of sloths, a better known soporific mammal). This slow movement however, doesn’t mean that the Loris has nothing to fear in it’s native jungles, rather using its slow and steady pace to move through the night in almost perfect silence, becoming totally still when approached by a predator, and capable of surprising bursts of speed when in danger. Perhaps most interesting of all, the Javan Slow Loris, and indeed all Slow Loris, are capable of giving a toxic bite, a rare feature among mammals which is mainly seen in various kinds of shrew and vampire bat. A small gland on the arm of the Loris creates this toxin when mixed with the Loris’s saliva, not only allowing it a nasty bite, but also allowing the toxin to be groomed into the fur of juvenile Loris’ by their mothers, providing extra protection against opportunistic predators.

Due to the nature of the Night House, I was unable to take a picture of Berlin’s native Slow Loris, but I can provide a stock image.

The Javan Slow Loris, as its name might suggest, is endemic to the South East Asian island of Java in Indonesia, where the thick tropical jungles suit their arboreal lifestyle. The Javan Loris was originally classified as a Sunda Slow Loris, but small differences in size, fur length and geographical location lead to its reclassification. The are omnivorous, moving almost 20m up through the Javan canopy, eating fruits, bird eggs, small insects and reptiles, and even native cocoa beans (making them mutual lovers of chocolate with humans). They are totally nocturnal, relying on their large eyes and excellent sense of hearing for navigation, and stay curled up on branches during the day, often in pairs or larger groups, forming adorable collection of sleeping fluff balls hanging from the canopy.

Unfortunately, the Javan Slow Loris is considered critically endangered, in no small part do to their illegal trade as ‘exotic’ and interesting pets. They are easy to capture during the day as they hang from trees and their slow movement is desirable to pet owners. They are not, however, easy to keep, and pet Loris often become stressed and diseased without the correct care, and additionally, many Loris have their teeth pulled in order to prevent their toxic bites from affecting their ‘loving’ owners, which only adds to their suffering. Deforestation of the Java also contributes to the Loris’s decline, as (like the Giant Panda) the Loris is too slow moving to make it through the increasingly fragmented jungles, effectively isolating populations from each other. In light of their critical position and vulnerability as an endemic species, it was a real treat to see such a healthy Loris so close, and I hope that breeding and conservation programs between institutions like the Berlin Zoologischer Garten helps to alleviate the stress the species is under.