Our team has recently been following multiple flanged males in the Suaq study area. They witnessed numerous orangutans drawn to a site with abundant ripe Tampu Licin fruit, especially many flanged and unflanged males. Flanged males are generally intolerant of each other’s presence. Several of the flanged males in this area emitted ‘long call’ vocalisations, used to establish their dominance and alert others of their presence. Upon hearing this long call, we witnessed other males either travelling in that direction to challenge the caller, or quickly fleeing in the opposite direction, rapidly disappearing into the canopy, opting to avoid conflict. These observations will help us to disentangle the current dominance hierarchy among the flanged males at Suaq!
Photo & Video by Team SUAQ. Data & Pictures provided by the research teams of Universitas Nasional (UNAS), the Department of Anthropology at the University of Zürich (AIM), and the Development and Evolution of Cognition Research Group at the Max Planck Institute of Animal Behaviour (DECRG)