Slender Loris

The Red Slender Loris (Loris tardigradus) is a small, nocturnal prosimian native to the rainforests of Sri Lanka and Southern India.

There are two species of Slender Loris, the only members of the genus ‘Loris’: the Red Slender Loris (Loris tardigradus) and the Grey Slender Loris (Loris lydekkerianus).

Slender loris Characteristics

The Slender loris is a small, slender primate with large forward facing eyes used for precise depth perception. The Slender loris has long slender limbs, a well developed index finger, no tail and large prominent ears, which are thin, rounded and hairless at the edges. The soft dense fur is reddish-brown colour on the back and the underside is whitish-grey with a sprinkling of silver hair. Its body length on average is 7 – 10 inches (17.5 – 26 centimetres), with an average weight of a mere 3 – 13 ounces (85 – 350 grams).

The Slender loris has a 4 way grip on each foot. The big toe opposes the other 4 toes for a pincer-like grip on branches and food. The Slender loris has a dark face mask with a central pale stripe.

Slender loris Diet

The Slender loris spends the day curled up in a tight ball. It approaches prey slowly and carefully, before reaching out and grabbing it with both hands. Slender lorises mostly feed on insects, but they also eat shoots, fruits, leaves, flowers, eggs and small mammals, birds and reptiles. To maximize protein and nutrient intake they consume every part of their prey, including the scales and bones.

Slender loris Habitat

The Slender loris inhabits tropical rainforests, scrub forests, semi-deciduous forests and swamps. The Red Slender Loris favours lowland rainforests (up to 700 metres in altitude).

Slender loris Behaviour

Although they forage alone, slender lorises sleep in groups of 2 – 4. They spend the day sleeping in a tight ball up a tree and become active in the evening.

The Red Slender Loris differs from its close relative the Grey Slender Loris in its frequent use of rapid arboreal movement. It forms small social groups, containing adults of both sexes as well as young animals. The Red Slender Loris is among the most social of the nocturnal primates. During daylight hours the Red Slender Loris sleeps in groups in branch tangles, or curled up on a branch with their heads between their legs. The groups also undertake mutual grooming and play at wrestling. The adults typically hunt separately during the night. The Red Slender Loris is primarily insectivorous but also eat bird eggs, berries, leaves, buds and occasionally invertebrates as well as geckos and lizards. The Red Slender Loris makes nests out of leaves or find hollows of trees or a similar secure place to live in.

Slender loris Reproduction

Slender lorises breed twice a year, usually between May and December. The female Slender loris typically gives birth to one offspring, but sometimes two. Females are dominant. The female reaches her sexual maturity at 10 months and is receptive to the male twice a year. The Slender lorises mate while hanging upside down from branches. Individuals in captivity will not breed if no suitable branch is available. The gestation period is 166 – 169 days after which the female will bear 1 – 2 young which feed from her for 6 – 7 months. The life span of this species is believed to be around 15 – 18 years in the wild.

Slender loris Conservation Status

Slender lorises are considered to be Vulnerable by the 2000 IUCN Red List. The Red Slender Loris is an endangered species. Habitat destruction is a major threat. It is widely trapped and killed for use in supposed remedies for eye diseases and also for use as laboratory animals. Other threats include: electrocution on live wires, road accidents and the pet trade.

Grey Slender Loris

The Grey Slender Loris (Loris lydekkerianus) is also found in India and Sri Lanka. Its natural habitats are subtropical or tropical dry forests and subtropical or tropical moist lowland forests. It is threatened by habitat loss. The species used to be considered as Loris tardigradus lydekkerianus but Loris tardigradus is now a separate species found in Sri Lanka.