Monkey Business: Living with Macaques in Urbanised Singapore

Singapore's increasing need for housing has led to development encroaching onto the edge of nature reserves, the home of wild creatures such as macaques. And there are challenges as nature brushes against human comforts, with macaques being lured towards entrapment and taken away permanently from their natural habitats.  Fiona Childs speaks to primatology student Amanda Tan on these issues, to explore how residents can better manage the situation, and to put the whole monkey business to a rest.

Long tailed macaques are an endemic Singapore species. And each one of them is unique with a distinct personality.Singapore, 10 June 2013. What do you see when you look out your window?  I feel incredibly fortunate to live in close proximity to Bukit Timah and Bukit Batok Nature Reserves in Singapore and I see regularly butterflies, birds, lizards and tree shrews. The most charismatic and entertaining visitors though, are the long tailed macaques.   

The ‘Hindhede group’ named after the small road that separates the jungle from the condominiums regularly travel through the buildings.  They have discovered easy sources of human food on the way such as rubbish bins and some have entered apartments through open windows looking for more.  This “monkey menace” has led to concerns from some residents about health risks and the safety of their families.

Trapping macaques to remove them followed by euthanisation is not an ecologically sustainable solution.In response traps have been set up and any macaques caught are euthanised.  While the culling is supported by some it is strongly opposed by others, emotions are running high over this controversial issue.   So as urban development increasingly encroaches on green areas, how can we find a way to live harmoniously with nature?

To try to find the best way forward, residents were invited to a discussion with a panel of concerned parties.  The panel included Mdm Halimah Halimah Yacob, MP for the area and Speaker of Parliament, the chairman of a Residents Committee, members of the condominium management and Louis Ng from ACRES, (Animal Concerns Research and Education Society).  There were also representatives from NParks (National Parks Board Singapore) responsible for the macaques inside the reserves), AVA (Agri-Food and Veterinary Authority) who take over this role if they leave and NEA (National Environment Agency) who are investigating the use of monkey-proof bins.

Macaques like to live at the edge of the forest; as such, they like walking about, exploring open spaces just like humans do.Sometimes what seems like a good idea may not work in reality, so it was very positive to have a panel that were able to provide informed suggestions and feedback.  For example, one solution put forward was to plant more fruit trees in the nature reserve to encourage the macaques to stay in the centre of the forest.  

However, the NParks representative explained that according to regulations, only native plants can be planted and Amanda Tan, a field primatology student, added that macaques are a periphery species; as such, they stay at the edges of forests - a strategy that probably evolved through predator avoidance.  This kind of expertise is essential in planning effective solutions.  The key is understanding macaque behaviour.

Gaia Discovery learns more from Amanda.  

How long have you been studying macaques? 

About three years. I had my first experience studying macaques before I entered graduate school, as a field assistant on a project that investigated how the availability of natural food resources and human provisioning affected the feeding ecology and ranging patterns of two groups of long-tailed macaques in Singapore's Upper Seletar Reservoir Park. 

You have followed the Hindhede troop for some time now, what can you tell us about the individuals within the group? 

Three's never a crowd with a family of macaques, famously known as the Hindhede troop near Bukit Timah nature reserves. Greg (far right) has been missing, according to Amanda Tan.They are exactly as you say, individuals. Once you've observed them for a while you'll start to notice that not only do they look different, they have very different personalities. I try not to humanise them too much but sometimes it's difficult. Their personality differences show even when they are little juveniles. Some of them are extremely curious and playful, and they'll be jumping on each other all day. Others are quieter, I think of them as the introverts (she laughs). 

The really good thing about this group is that while they are really habituated to people, none of them are aggressive or problematic in constantly harassing or attacking people. A sad thing happened recently. One of the little males that I've named Greg went missing. I think he's been taken by one of AVA's traps, and its sad because he was not a problem individual, mostly just played with other juveniles and still suckled his mum sometimes. Trapping a monkey like him doesn't help to solve human macaque conflict at all. 

At the discussion session people said that the macaques have only started to be a problem in the last two years, why do you think this is? 

People aspire to live near nature, yet they are afraid of nature. Learning about macaque behaviour helps them overcome fears and doubts, says Amanda Tan, primatology student with NTU.I think that a huge part of the problem is the significant environmental changes that have taken place within the home range of these macaques. Two new residences have been built right on the edge of the Bukit Timah Nature Reserve in recent years, Raintree in 2008, and Mont Timah in 2010. Each time you do this, you move hundreds of people into macaque range. 

Despite being so close to a reserve, these residences are not built to be wildlife proof - buildings are easily climbable, rubbish points are not monkey proofed, guards are not trained to deter monkeys etc. Many residents are also unprepared to live so close to wildlife; they leave windows open and unprotected, carry food in plastic bags, and cultivate fruit trees. The monkeys learn more and more that human residences are an easy source of food, especially the rubbish disposal areas. 

Many people are scared of macaques, fearing that they will be aggressive.  Are you aware of any instances of aggression and what can people do to avoid this? 

Signage on dealing with macaques is useful.Aggression by macaques towards humans is actually very rare, and when it happens, usually involves only mild aggression like a facial or vocal threat. Occasionally people are chased. Skin-to-skin contact resulting in scratches and bites are extremely rare, I have never personally observed it, but the media does sensationalise it when it happens. 

All instances of aggression I've observed could have been easily avoided. The most common would be macaques snatching food from people, so just don't carry food or plastic bags around them. If you're going grocery shopping, always keep a couple of recyclable canvas bags on hand. If you do find yourself with food, carry it close to your chest or above your head and walk away. 

It is also really important to understand aspects of macaque behaviour and how to behave around them. Keep a respectful distance, especially from young individuals as their mums can get defensive, and from adult males as some might see your approach as a challenge. Don't stare as eye contact can be seen as a challenge, just lower your head and walk calmly. Juveniles can be curious and approach you, and it is important to stay calm when this happens. If you freak out, the little one will get scared and the adults will come to its defense. Avoid going near the macaque group if there is some sort of commotion going on, as all the creatures are in a high state of excitement so you may get charged at. In the rare case that you are charged, run. Once they see that you are leaving, they will leave you alone. 

Having studied macaques do you think it is possible to change their behaviour now that they have learned to come to the condos to find food? 

Disposing bags outside of bins simply attracts the wrong kind of scavengers. Monkey proofing bins is an important way of keeping macaques off residential premises.Definitely. Macaques in places like Bali or Lopburi sit around all day waiting to be provisioned, but our macaques still spend a lot of time foraging and feeding on natural food sources and haven't lost their taste for the natural. Their consumption of human foods is very opportunistic; if a dustbin is easy pickings or a window is open then they might try their luck. All we have to do is make sure we do not provide them with these opportunities. It has to be a collective effort from all residents, park visitors, researchers who can make recommendations based on knowledge of macaque behaviour, and government agencies with the resources to do things like monkey proof all bins and building structures. 

One of the strategies being used is catching macaques in baited traps and euthanising them, do you think this is an effective solution?  Is there evidence that the population needs to be controlled? 

I don't think this is a solution at all. Many people think that there is some kind of population explosion that accounts for the increase in "monkey nuisance", but Singapore's macaque groups resemble wild, undisturbed, macaque groups in terms of group sizes, population densities and structures so macaque numbers are not yet a big driver of conflict. A group of 10 macaques will come into as much conflict with human neighbours as a group of 25, so any form of population control will be ineffective as long as people allow them such easy access to food. Human behaviour change and monkey proofing the environment is key. 

There is also the issue of safety when traps are used, especially in residences. When a monkey gets trapped, it will call in distress, and this can send the whole group into a high state of distress as well. People may find themselves in the wrong place at the wrong time, and be attacked as a result of displaced aggression. 

When I think it becomes necessary to remove a monkey from the population, is if there is an individual that is particularly aggressive, and has caused bodily harm to people. In this instance the trapping should be targeted, and should still be done as ethically as possible, for example with the use of tranquilizer darts by trained wildlife vets. Hopefully in future, there will be a sanctuary for these problem individuals to live out their days. 

What long term solutions do you suggest avoid further conflict between residents and macaques. 

Macaques are curious and may eat your leftovers after foraging through rubbish bags, so it's important to keep plastic bags full of food or trash away from their sight.We need to cut off all sources of human foods for the macaques. We can start monkey-proofing residences; for example, Louis (from ACRES), suggested the use of electrified fences that have been successful in keeping out wildlife in places such as South Africa, and also monkey-proof all rubbish points. All future residences that are built within macaque home range need to be planned better, constructed such that monkeys cannot climb into houses. 

Awareness raising and education are also important as people need to change their attitudes towards wildlife and behave more responsibly, and this can only happen when people understand them more. We can run programmes for the residents to learn more about macaques, and hopefully help them with their irrational fears and misunderstanding of macaques. All potential residents need to be made aware of the potential interface with macaques, so they can make an informed decision on whether they are willing to do things like mesh up windows or keep them closed to prevent unwanted entry. There will be no bad blood between macaques and residents who understand the issues and are happy to live responsibly. 

Ultimately, people must be willing to actively resolve the problem. Monkey-proofed bins will not work if people do not dispose of rubbish correctly. Monkeys will continue to see people as sources of food if people continue to feed them, either deliberately, or accidentally, by carrying food or plastic bags and having these items snatched from them. After all these efforts, residents also need to be more tolerant, and accept that they will come into contact with wildlife at some point, but this is not cause for alarm, rather, it is a privilege to be able to experience these close encounters, and an opportunity to learn more about animals that share our world. 

If people want to learn more about macaques can you recommend any sources of information? 

I think the best way for people to learn about macaques is to spend some time observing them, and seeing for themselves their individuality, their social behaviours, the antics they get up to, and watching how they interact not only with each other, but with people. I have no doubts that people will appreciate macaques more and learn that they are not menacing pests, if they put aside their fears and biases and take some time to get to know them. 

Human-macaque conflict... it is time to kiss and make up.NParks runs a monkey walk programme once or twice a month, where you can go on a guided walk with the Hindhede group and learn more about the individuals in the group.  Someone will be there to teach you how to behave around monkeys and to answer your questions about them. People can also contact me, as I will be happy to introduce them to the group as well! Follow me on Twitter (@thelongtails) and send me a tweet, or drop me a Facebook message ( 

Amanda Tan is a graduate student training in field primatology at Nanyang Technological University (NTU), under the supervision of Dr Michael Gumert, an expert on long-tailed macaques. She studies long-tailed macaques in Thailand, where she investigates skill development in populations of coastal-dwelling macaques that use stones and shells as tools to crack open oysters and other shelled foods, and in Singapore, where she is involved in efforts to ameliorate human-macaque conflict. 

You may also want to check out these links for more information: 

Michael D. Gumert, How macaques and humans can live together in Singapore

Want to know more about wildlife in Singapore?  Check out this facebook interactive infographic from ACRES. 

‘Advisory on keeping Monkeys at Bay’ by AVA PDF file

Watch Channel NewsAsia interview with Louis Ng on euthanising macaques.

Photography by Fiona Childs and Amanda Tan.