Symphalangus syndactylus

[Translate to English:] IUCN Red List endangerment category: Endangered
  • Weight
    11 – 12 kg

Just swinging

The siamang live in treetops. It moves by swinging handover- hand from branch to branch. When moving quickly, it often releases the previous branch before grabbing the next – fl ying freely through the air. Its powerful shoulder joints are specially adapted to this form of locomotion with 360 degree rotation. The long arms allow it to hang with one arm and swing out to grab diffi cult-to-reach fruits at the end of branches.

The picture shows a free swinging siamang holding on to a rope with his right arm.

Singing ape

Siamangs mark their territory by singing – their distinctive, loud calls are known as songs. They start their day by singing in the early morning and can be heard kilometres away. The call is resonated in throat sac, which can be infl ated to the size of their head. Siamangs typically sing duets, performed by mated pairs, which also serves to strengthen their bond. If an intruder fails to heed the call, it will be chased out of their territory with slaps and bites.

The siamang has webbing between its second and third toes, which is one of the main features used to identify the species.


Distribution Siamang