Population Survey of Bornean White-Bearded Gibbon, Hylobates albibarbis,in Two Selective Logging Concessions in Central Kalimantan and West Kalimantan.

We surveyed Bornean white-bearded gibbon, Hylobates albibarbis, population densities in lowland and hill dipterocarp forests within the Sari Bumi Kusama and Suka Jaya Makmur logging concessions. These surveys were conducted from 20 to 30 March 2018 in Sari Bumi Kusuma areas and 14 to 24 April 2018 in Suka Jaya Makmur. We used a fixed-point count method to detect and plot morning song bouts of gibbon groups at systematically placed listening posts.