Forgotten Species - The Proboscis Monkey

Release date: 03 May 2011

Raising awareness is essential for the survival of some of the world's 'forgotten species'.
Photo: Bjorn Johansson/PFC
Photo: Bjorn Johansson/PFC

The peculiar looking Proboscis monkey (Nasalis larvatus) is endemic to the south-east Asian island of Borneo. It lives near water, such as coastal lowland forests, mangroves and riparian forests. Groups of up to 30 individuals may be found high up in trees eating leaves, seeds and fruits. Bacteria in their large bellies help them to digest cellulose and neutralize toxins from certain leaves.

They are excellent swimmers. This enables them to move between feeding grounds, cross rivers and even visit islands off shore. Proboscis monkeys have been seen as far as a mile away from land swimming in the open ocean.

Photo: Bjorn Johansson/PFC
Photo: Bjorn Johansson/PFC

So what about their long nose? It may actually reach a length of almost 20cm. Its function is not known for sure, but it is believed to be a visual signal in mate choice. Males have larger noses than females. The characteristic protruding nose may also serve as a resonating chamber, amplifying their warning calls.

The Proboscis monkey is classified as endangered by the IUCN Red list. The total population may be as small as a few thousand individuals and is currently declining. They are locally hunted for human consumption. Body parts are also sold and used in traditional Chinese medicine. Also deforestation and conversion of land to oil palm plantations mean loss of suitable habitat for the monkeys. Other threats to this fascinating species are increased human activities nearby rivers, unmanaged tourism, pollution, recreational hunting and fish and shrimp farming.

While another primate of Borneo, the Orangutan gets lots of attention, the Proboscis monkey and its situation are often overseen. Its future existence may very well depend on increased awareness and attention to its situation.

Find out more about the concept of forgotten species on the website of the Photographers for Conservation and how they work to raise awareness about threatened nature.

Photographers for Conservation provided EOCA with many of the wonderful wildlife images on this website.

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