THE Sangkulirang limestone mountains in the East Kalimantan district of Kutai is a largely inaccessible forest area. There were rumors that a significant population of orangutans live there. Erik Meijaard, a senior ecologist of The Nature Conservancy (TNC), was excited with finding the truth to the rumor.

“Since I first surveyed the vicinity of these mountains in the mid-1990s, I have heard rumors of orangutans in these largely unexplored part