Sunda flying lemur: where and when to see them

The Sunda flying lemur is a colugo, not a lemur, and it glides rather than flies. A broad skin membrane links its neck, limbs, fingers, toes and tail, creating an unusually extensive gliding surface. Its mottled coat blends closely with bark, making a resting animal surprisingly difficult to notice. Native to parts of Southeast Asia, this tree-dependent mammal can occupy some modified wooded landscapes, but continuous canopy remains important for safe movement.

Size

33–42 cm head-and-body length

Weight

0.9–1.8 kg

Lifespan

Not reliably established

Status

Least Concern

Colugos usually rest against trunks or beneath branches during daylight, becoming active around dusk. They climb with short, awkward-looking hops before launching into controlled glides between trees. A mother carries her dependent young against her abdomen, with the folded membrane helping support it. Animals may repeatedly use favored resting trees and feeding routes. They are generally quiet and inconspicuous, and a motionless individual can resemble a knot or patch of lichen on bark. Their gliding ability is highly efficient, allowing them to travel distances of up to 100 meters or more between trees with minimal altitude loss. They are often solitary but occasionally seen in small groups, particularly mothers with young or at favored feeding sites.

• Colugos belong to their own mammalian order, Dermoptera.
• Their lower incisors have comb-like divisions.
• Young remain attached to their mother while she glides.
• Colugos are among the closest living relatives of primates.

There is no well-supported general seasonal peak for viewing this nocturnal mammal. Locally drier months can make permitted forest walks more practical, but activity is primarily governed by darkness and weather. Quiet dusk observation near suitable trees is more useful than a breeding calendar. While largely nocturnal, observing them during a clear, moonlit night can sometimes enhance visibility as they move between trees. Local guides in Indonesia and Thailand can often advise on specific sites where they are regularly seen, regardless of the time of year.

Lowland tropical forests are central habitat, including evergreen woodland and some forest edges, plantations and wooded gardens. Suitable sites need connected trees for feeding and gliding. Broad roads, extensive clearings and intensive development can interrupt otherwise usable canopy routes. They are particularly abundant in primary and secondary rainforests, often found from sea level up to 1500 meters. The species prefers areas with a dense canopy providing both cover and food sources across its range in Indonesia and Thailand.

The diet consists mainly of young leaves, supplemented by buds, shoots, flowers and some fruit. Colugos select plant material in the canopy and have a digestive system suited to processing fibrous food. They do not hunt insects or other animals. Despite their name, colugos are not true lemurs and are entirely herbivorous, consuming high fiber foods that require a long digestive tract. This specialized diet means they often spend significant time foraging and digesting in the canopy.

Common name

Sunda flying lemur

Scientific name

Galeopterus variegatus

Animal group

Mammals

Size

33–42 cm head-and-body length

Weight

0.9–1.8 kg

Lifespan

Not reliably established

Status

Least Concern

Identification

Its continuous membrane encloses the tail and extends between the fingers and toes, unlike a flying squirrel's less extensive gliding membrane. The Sunda flying lemur has a distinctive fur pattern, a mottled grey or brown that camouflages them effectively against tree bark. Their large, forward facing eyes are adapted for excellent night vision, a key identification feature at dusk.