TANJUNG BUNGAH, Malaysia — When Yap Jo Leen was tracking dusky langurs in the forests of Penang for her master’s degree in 2016, she watched a langur they called Towkay Soh — Hokkien for “lady boss” — get hit by a car while trying to cross a busy coastal road. Dazed, the langur managed to get back on its feet and retreat into a tree while Yap and her colleagues blocked traffic.
As Towkay Soh recuperated over the next few days, the langur group’s empathy for each other was on full display, Yap says.
“Female individuals, they would approach her and groom her and even try to make her feel better,” Yap says. “I always believe that the primates, humans and monkeys, we all share a similarity, which is connection.”
Other langurs weren’t so lucky. From 2016 to 2018, Yap recorded eight langur roadkill deaths in the same area.
So, in 2019, Yap and her collaborators built an artificial canopy bridge over the road, made from old fire hoses. Since then, they’ve recorded zero langur roadkill deaths in the area, Yap says.
Since 2023, the group has built two more canopy bridges on Penang Island. Besides reducing roadkill and mitigating human-wildlife conflict, the bridges serve as a tool for environmental education on an island where rapid urbanization and habitat loss is driving people and primates into contact.
To study the langurs and help people learn to share an environment with them, Yap deploys a team of volunteer citizen scientists who track langur movements, collect data, and record GPS coordinates, under the banner of an organization she founded, the Langur Project Penang (LPP).
LPP also conducts outreach into local communities to teach people how to coexist with wildlife. A former citizen scientist now leads LPP’s environmental education program, which involves conducting training for schools and companies. They have a partnership with a local international school, for example, to teach kids how to develop a system of codes for studying Penang’s exotic squirrel species on their campus and log their behavior. Revenue from the program feeds back into LPP’s conservation work.
“Primate observation is more than just scientists’ work — it can be everyone’s hobby, like bird-watching,” Yap says.
Yap spoke with Mongabay’s Philip Jacobson and AFP’s Isabelle Leong in Tanjung Bungah, the site of one of LPP’s canopy bridges, about her work in Penang. The following interview has been lightly edited for length and clarity.
AFP and Mongabay: What is the Langur Project Penang and how did it start?
Yap Jo Leen: LPP is a primate conservation enterprise that’s focused on fostering coexistence among humans and urban wildlife, especially nonhuman primates, a.k.a. monkeys. We work on three pillars: First is citizen science; second, environmental education; and third would be scientific conservation projects such as the installation of canopy bridges.
AFP and Mongabay: What prompted you to launch LPP, and what gap in conservation are you trying to address?
Yap Jo Leen: I started Langur Project Penang from a simple Facebook page back in 2016, when I was just starting as a postgrad student working on my master’s and Ph.D. I just worked on it as a journal online to share my experience working in the secondary forest of Penang, and also to talk about the individual langurs that I knew from my observation. And eventually it just grew, and I had very huge support from my supervisor and co-supervisor from that time, Dr. Nadine Ruppert and Dr. Nik Fadzly. They encouraged me to do my own thing. So I feel that the opportunity and freedoms that I gained helped me to develop LPP into a primate conservation enterprise, which we came a long, long way.
I feel like for the youth nowadays, they are not given a lot of opportunities in terms of gaining hands-on skills in on-the-ground grassroots conservation efforts. So for Langur Project Penang, we have shifted from just pure research more towards community engagement and citizen science initiatives, which I would like to provide more opportunity in terms of capacity building as well as career chances for the youth and also the existing generation around us.
AFP and Mongabay: Can you tell us more about these dusky langurs?
Yap Jo Leen: Dusky langurs, they are indeed my favorite species of primate, better than human primates [laughs]. We can actually find them not only in Peninsular Malaysia but also Myanmar and Thailand. We address them as “arboreal” primates because they rely on canopy and treetops for survival. So they need certain food plants, which are high up in the canopy: fresh leaves, fresh fruits, fresh flowers and seed pods. We can find all these plant varieties not only in the virgin forest but also in secondary forests, even green spaces around our residential area.
Dusky langurs, they have white spectacles. This gives them many nicknames: Some people call them the dusky leaf monkey or even spectacled leaf monkey; some people call them the white spec monkey; some people call them the black-and-white panda monkey. So I think this uniqueness of the white marking among the black-grayish fur, it leaves a very good impression in people so that people can see them as an adorable species, and at the same time as something to remember from Peninsular Malaysia.
In Penang, we are very lucky to find dusky langurs as the ambassador species, where a lot of tourists from all around the world will drop by Penang just to do monkey observation or nature appreciation as a whole. Even though it’s the second-smallest state in Malaysia, Penang is such a rich-biodiversity landscape that I think as Penangites, we really need to educate further for more Penangites to truly appreciate the value of coexisting with our nature.
AFP and Mongabay: Are there misconceptions that people have toward dusky langurs?
