What are
Raffles’ Banded Langurs?

Presbytis femoralis

The Raffles’ banded langur (Presbytis femoralis, Lotong Cenekah), also known as the banded leaf monkey or banded surili is a critically endangered species of primate, found in Singapore and Johor and Pahang in Southern Peninsular Malaysia.

Why should we care about Raffles’ banded langurs? These creatures are the largest and rarest non-human primates native to Singapore still in existence. They are important representatives of Singapore’s natural heritage. We should care about all living creatures. Animal Concerns Research and Education Society (ACRES) has a good explanation of why we should help animals and how similar we are to them.

Sir Stamford Raffles spots a langur

Sir Stamford Raffles noted the existence of these primates in 1821 (initially described as Semnopithecus femoralis), identifying them as the “Lotong of the Malays”. In 1838 a naturalist named William Martin formally confirmed and described the new species.

Critically Endangered

There are around 70 in 2022 in the Central Catchment Nature Reserve, including the Nee Soon Swamp Forest, feeding on leaves, fruits and seeds. An estimated 300 Raffles’ banded langurs live in Malaysia.

They are shy and elusive, skilled at balancing, leaping and swinging from tree to tree, rarely coming down to the ground. Males and females look quite similar and sport white bands on their underside and black fur on their body. In Singapore, they are the largest non-human primate still in existence.

In the 1920s, you could find Raffles’ banded langurs in Bukit Timah, Changi, Tampines and Tuas (Chasen 1940 cited by Ang & Jabbar 2022).

Threatened by deforestation

The main threat to the population in Singapore is habitat loss. That is, deforestation caused by development for transport and housing. Only 200 hectares of Singapore’s original primary forest remains. Other threats include poaching activities, low genetic variability and inbreeding.

Concerns have been raised that the construction of the Cross Island MRT line through The Central Catchment may adversely impact the Raffles’ banded langurs in the area.

Recently, a langur was trapped in a canal at Yio Chu Kang until it was rescued by (ACRES) and several Raffles’ banded langurs were killed on Singapore roads.

This comprehensive NUS Wiki on Raffles’ banded langurs states:

“The popular recreational area of Singapore, Bukit Timah Nature Reserve (BTNR) used to house the banded leaf monkey [3] [1]. However, due to the construction of an expressway (Bukit Timah Expressway) in 1983 that separated BTNR from CCNR, gene flow stopped and the last banded leaf monkey of BTNR was then found dead in 1987 (figure 7)[3] [1] [27]. The last banded leaf monkey was an elderly female believed to be mauled by a group of dogs as she descended from the tree, of whether she is committing suicide or not is based on speculations [3] [1].”

The last banded leaf monkey from Bukit Timah Nature Reserve is now kept as part of Raffles Museum of Biodiversity Research taxidermal collection.

Listen to primatologists

The foremost expert on Raffles’ banded langurs in Singapore is Dr Andie Ang, Primatologist. She has done a lot of research work on Raffles’ banded langurs and is a member of the Raffles’ Banded Langur Working Group. Here’s her TedTalk.

This is a good summary if you want to know more about Raffles’ banded langurs with discussion on Singapore and Malaysian conservation collaboration.