Knowing how to compete with other orangutans while foraging is one of the most critical skills an orangutan needs to survive in the wild. Each orangutan eventually learns about this, sometimes the hard way! Find out how Desi, a 19-year-old female orangutan who resides on Juq Kehje Swen Island, learned about foraging competition.
Desi, the only orangutan currently undergoing rehabilitation on Juq Kehje Swen Island in East Kalimantan, receives fruits and vegetables to supplement her diet. Our monitoring team delivers food to the island daily, usually in the afternoon.
Juq Kehje Swen Island, located about 10 kilometres from the Kehje Sewen Forest, is a man-made 82.84-hectare forested island. We currently use it to accommodate orangutans undergoing the pre-release stage of rehabilitation.
Since a river surrounds the island, we deliver the food to Desi by a motorised longboat, locally known as ces. When Desi hears the sound of the approaching ces engine, she will immediately rush to the feeding platform and wait for the technicians to unload.
However, there are often prying eyes spying on the team and Desi: a group of wild and bold macaques. If a team member, or Desi, lets their guard down even for only a moment, the macaques will quickly rush over to steal Desi’s food.
Despite being unable to stop all of them, Desi will safeguard her food as much as possible, especially if there are any mangoes – her favourite fruit! Initially, the monitoring team didn’t wait around for Desi to finish eating, as she is not a picker eater and would eat all the food given to her. Now, given the frequent stealing of Desi’s food, the team has changed tactics and will only leave the island once Desi has eaten all of her food.
Keep a close eye on those thieves, Desi!