Apenheul: Javanese langur
The Javanese langurs in the Apenheul get a high-fiber and low-sugar diet. They eat a lot of (young) leaves, spinach, endive and chicory. They get relatively few fruits here, because the fruits available here contain much more sugars and less fiber than the fruits from the wild. If they eat too much fruit, they would become too fat.
Javanese langurs come in two color variants: orange and black. However, the color has nothing to do with their gender. It is true that you often find Javanese langurs with orange fur in zoos than in the wild. In the wild, the orange variant only occurs in one place in East Java. The Javanese langurs have a long tail. Their hair around their face is upright and waves slightly forward.
Javanese langurs live on the islands of Java, Bali and Lombok (Indonesia). There they live in the tropical rainforest, deciduous forests, mangrove forests and swamps. Javanese Langurs are real leaf-eaters. In order to be able to grind all those leaves properly, they have special molars. They also have an adapted gastrointestinal system to digest leaves properly.
Javanese langurs live in groups of an average of eight animals. One male is the (harem) leader. This group form is also called a harem. There are also sometimes men's groups. However, leaders do not always have an easy time. Because sometimes there are other men who want to take over the leadership.
Javanese langurs are fairly calm animals. They use their energy efficiently. This is more common in monkeys that eat a lot of leaves. After all, leaves are difficult to digest, so it takes a lot of energy to digest. Because leaves also contain little energy, the langurs rest a lot. Javanese langurs communicate with each other mainly with sounds. Is there an alarm? Then they hear a loud call that sounds like 'ghek-ghok-ghek-ghok'.
