Written by our wonderful guest blogger; Rick Wood.
Signals and Misunderstandings
It was hot and muggy. I'd been in the field for three hours already and the humidity wrapped itself around me like a wet blanket. Above me, I could see blurred movements and then the telltale fall of leaves confirmed their presence. The monkeys were on the move again.
I watched an Indonesian family walk along the path in front of me. Seemingly all at once a horde of macaques descended the trees and encircled the people. A young girl shrieked as monkeys galloped towards her while reaching their hands out at the hem of her dress. The girl's father lightly chuckled, remained calm and pulled her in close.
Darting in and out of the bushes, a trio of small monkeys continued to try tagging the girl. After a few moments, the troop continued on its way and the nonreciprocal game of tag ended.
Luckily, in this situation, the human adults read the behavior as playful and not an aggressive attack by the macaques. All too often fear escalates what would normally be a non-aggressive situation.
An adult and juvenile long-tailed macaque interacting. Image taken by Rick Wood (used with permission).
The Mangrove Ecotourism Centre PIK, in North Jakarta, is a compact public park surrounded by urban development and hemmed in by highways and roads. It's within the one-kilometer long protected mangrove conservation area that a troop of wild monkeys live and thrive.
The troop (Troop Bravo) of 23 long-tailed macaques (Macaca fascicularis) live primarily in that narrow strip of protected mangrove forest. The park sees hundreds of visitors each day. It's here that I observe the small primates and record data about their behaviors as part of a long term citizen science hobby.
Although it is technically forbidden, feeding the monkeys human foods is a common practice. Park rules and signage warn people not to feed or harass the macaques, but the feedings happen daily. In this sense, the troop is provisioned by the visitor's actions. Therefor, the macaques rely on handouts for a certain percentage of their diet. Part of my study is gauging how high that percentage is and how it affects the relationship between humans and monkeys (also, between troop members). When I started my observations in November of 2021, the potential for provisioning to lead to aggressive behaviors by the monkeys seemed likely.
However, after a year of observations, my initial assumption that conflict and aggression only centered around provisioning turned out to be somewhat false. Another clear cause and effect for many negative human and macaque interactions is misinterpreted nonverbal communication.
Monkeys communicate in subtle ways that may not make sense to most people. Signs of aggression, like a wide mouth yawn, slack-jawed gaze, and piercing stares can be seen as innocuous behaviors. When these warnings are misread, problems can ensue.
Public opinion about the macaques range from pest to adoration, with the majority of people likely seeing them as “funny nuisances.” Fear of monkeys is common, and with good reason. Macaques can be aggressive, likely carriers of several serious diseases, and are unpredictable around humans. Monkey bites on people, even fatal ones, occur annually throughout Southeast Asia. In fact, Bali, Indonesia is reportedly the top spot for macaques attacking people. It is also fair and accurate assessment to say that the many people are not greatly concerned with the conservation of monkeys. Still, the macaques are an endearing draw to the mangrove parks for many people, who enjoy watching their foraging and playful antics.
Figure 1 & 2: grapgical respresentations of some of the key information Rick has been collecting.Figure 1 (top) looks at the prevelance of different types of conflict seen between macaques and people. Figure 2 (bottom) examines the rates of human and macaque numbers during various days of observations. It also records the number of conflicts observed on the day. Both figures produced by Rick Wood.
Coexistence
Peaceful cohabitation will determine the future of Troop Bravo. Any escalation in conflicts could likely lead to human injuries, monkey fatalities, park closures or more long term eradication methods of the macaques as pest control.
The reasons for conflict occurrence and ways to mitigate them are at the heart of my observational study. In short, I hope to learn useful information that may someday save people from injuries or illnesses, and preserve the safety of the monkeys in the endangered mangrove environment. To that end, education will be the deciding factor.
Conflicts occur in several ways. The macaques congregate as a troop. So, there are times that all 23 members of Troop Bravo will take up residence on the main pathway. Mainly, people yell at or charge at monkeys to make them move from a certain spot in order to move past the monkeys. A combination of close proximity and intentional or unintentional provisioning often sets the stage for human versus monkey situations. Almost all of the incidents of charging, chasing and grabbing are centered around foods. Still, a few outlier aggressive moments stem from a more complicated social response to stimuli. Sometimes, it's the social order and age of the macaques that pressures aggressive responses to human proximity.
I observed juvenile males, who attempted to mate with a few juvenile/sub adult females, taking a small "gang" of young adults and juveniles to roam further afield from the main troop. While attempting matting outside of hierarchy, the young males are more anxious and nervous. The on edge feelings make them more aggressive and likely fuel their need to look strong and ferocious in front of potential (albeit clandestine) mates.
These roving juvenile gangs are short lived gatherings and if the main body of the troop - especially the troop leader adult male- are within visual proximity, the rogue band disperses fairly quickly.
A human off-camera hands food to a juvenile macaque. It's interactions like these that lead to conflict between monkey and human. It also increases the likelihood of disease transmission and injury (to humans or monkeys). Wild primates should NEVER be fed. This is the reality in many places worldwide where monkeys live alongside humans. Photo taken by Rick Wood (used with permission).
Macaques need to navigate human altered environments, which can mean coming into contact with human waste. The monkeys are opportunistic and will forage for food where they can. Photo taken by Rick Wood (used with permission).
Understanding Macaques
Rarely do I witness the troop scavenge for human foods during times when the park is devoid of guests. Instead, the monkeys spend equal time foraging and socializing in peace.
When the troop moves throughout the park they typically follow a sort of routine. The long-tailed macaques nest in the tree canopy near the rear of the park. They will normally settle in after sunset, sleep through the night, and awaken at daybreak, or soon after. Like some people, the monkeys can sometimes be slow and languid right after waking up. Still, adult members will descend to the forest floor and other troop members eventually follow.
Their morning routine is to source breakfast. They forage from trees, bushes, other plants, and will opportunistically eat invertebrates or insects. As they move through the park they rummage through garbage cans and examine discarded litter for anything edible. If the macaques are unimpeded by human activities, such as park visitors, horticultural staff working, or fishermen on motorbikes, they will slowly make their way towards the park entrance area. Parked motorcycles and filled trashcans are rifled through along the way. The troop will continue to eat and forage throughout the day.
An adult female macaque with her infant clinging to her stomach. Photo taken by Rick Wood (used with permission).
The movement of the troop is typically unhurried. Troop leader Mal takes a vanguard position, and the rest of the troop follows where he goes.
Statistically, how they spend their time each day provides insight into their needs and wants. Foraging and scavenging account for 25 - 30 percent of the troop's waking hours. The long-tailed macaques also spend about 30 percent of their time in movement throughout the park. The monkeys rest, socialize, play or copulate for the remainder of their waking day.
Interactions between human beings and macaques happen daily. On average, the monkeys interact with people five to 10 times on a weekday, and more than 20 times on weekends or holidays, when the park sees a higher volume of visitors. Of those human/monkey interactions, roughly 15 percent involve any aggressive behavior by the macaques. Most interactions are benign, and involve elements of curiosity, begging for food, play or indifference.
As the day progresses, the troop makes a circuit, traveling the length of the park and the flanks – from estuary shoreline to mangrove seedling forest – more than a few times. Near sunset time the monkeys return to the area of their lair. Troop Bravo nests in the same tree canopy nightly.
For the long-tailed macaques of North Jakarta life is a careful dance of peaceful coexistence.
A long-tailed macaque in a tree, looking into the distance. Photo taken by Rick Wood (used with permission).
About the author:
Rick Wood is an award winning journalist and author. His books on ecology, conservation, and endangered species include: The Human Snare (2020), Rough Cut: Lessons from Endangered Species (2017), and Nature Aware (2012).
“The beauty of life is that we all play a role in an amazing and continuing cycle. From my youngest days I can recall a fascination with animal species, large and small. I very much wanted to better understand my place in the world.
Years later, I studied anthropology in university and became interested in primate studies.
My formal education includes Austin Community College, Indian River State College, and most recently certification from Kyoto University online.
Additionally, I've worked in animal rescue and have volunteered with animal rescue, rehabilitation and conservation of endangered species in the United States, Tanzania, China, Costa Rica and Canada, for a total of more than 15 years.
I live now in Jakarta, Indonesia with my wife and family. Our home, which is in a densely populated urban area, is less than 15 miles away from troops of wild monkeys. My curiosity now is to discover how well small primates and humans coexist in this area.”
To learn more about Rick's hobby of Monkey Watching and the results of his observations of Troop Bravo, please visit his website here.
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