The amazing orangutan long call

Orangutans are often regarded as being less vocal than the other members of the primate family. Though they may not speak up often, they are sure to get their point across when they do. This is especially the case for the male orangutan’s long call. This is primarily due to the fact that wild orangutans spend most of their lives alone, and sometimes the nearest orangutan could be miles away. 

With this great distance, it means that when an orangutan needs to communicate with others, they need to be loud. This is where the male orangutan’s long call is needed. The long call is a booming series of extended shouts that, under the right conditions, can travel for over a mile. The orangutan has a variety of important adaptations that can help produce this call.

The first of these is a large throat sac. The throat sac allows the orangutan to take a deep breath to power out this call. It also serves as a resonation chamber to help the call reach its full volume. Once the call escapes the orangutan’s mouth, the large cheek pads, or flanges, serve to direct the call forward and amplify it across a greater distance. The flanges work in a way similar to how you might cup our hands around your mouth when trying to call someone from a distance. 
 
The male orangutan’s long call serves a few purposes. He can use it to let females know where he is located, but he can also warn other males from entering his territory. Establishing territory is incredibly important to male orangutans. Breeding opportunities are difficult to come by for the solitary orangutans, so having undisputed access to nearby females is important. Also, their high caloric requirements mean that controlling a wide expanse of fruiting trees is a top priority.
 
Satu and Benny love to show off their long calls. They also have a tendency to get a little competitive with it. Typically, once one of the big boys starts calling, the other will be starting up as well within a few seconds. Maybe the next time you come visit, you might have a chance to hear for yourself. Lucky for you, they are pretty difficult to miss. Hopefully our neighbors don’t have any complaints.

Mike M.
Keeper II, Primates