“Monkey menace” emerged first & will likely be around a lot longer
BANGKOK, Thailand––Nightmares that a flying monkey army might ransack Thailand leaped across the Indian Ocean during the second week of March 2020, out of Hindu mythology and the daily fears of Buddhist temple keepers, and into the imagination of social media video-watchers around the world.
While much of the world remained riveted to scary television reports about the progress of the COVID-19 pandemic, “A video filmed this week in Lop Buri, 60 miles northeast of Bangkok, showed large crowds of monkeys brawling in the streets, apparently fighting over a yogurt pot,” wrote Rebecca Radcliffe for the Guardian newspaper chain.
Fighting in the streets
“Residents in the city, which is famed for its monkey population, say the fall in tourist numbers means there are far fewer people offering food,” Radcliffe explained.
Indeed, the 59-second video showed what appeared to be about 100 long-tailed macaques, also known crab-eating macaques, hanging out at an intersection that normally would host tourist buses and a busy open-air market.
Several cars and one motorcycle passed the macaques without incident, but immediately after a motorcycle with two passengers entered the intersection and turned toward the camera, fighting erupted among the macaques behind the motorcyclists.
Most of the other macaques ran toward the fight, some apparently rushing to the aid of friends and/or family members, while several of the largest and presumably oldest appeared to be trying to break it up.
Within a few seconds the macaques dispersed, going back to whatever else they were doing.
“Monkey menace” is nothing new
Thailand has seen this sort of thing before.
“Thais are fighting a crime wave. Falling tourist numbers have left monkeys so short of food they are taking whatever they can get from people’s homes, local media report,” wrote Soe Zeya Tun for Reuters in September 2009, amid nationwide civil disturbance preceding two coup d’etats in four years.
“As the global economic crisis and political instability has cut visitors to Thailand,” Soe Zeya Tun explained, “wild monkeys, mostly macaques, are attacking villages and even Buddhist monasteries across the country, pilfering everything that can be considered edible.
“In August,” Soe Zeya Tun recited, “hungry animals attacked a Buddhist monastery in Nakhon Sawan province, 120 miles northwest of Bangkok, ransacking the monastery kitchen, destroying furniture and part of the temple’s roof, media reports said.”
Already, in 2009, Thai local governments were aware of a growing need for macaque population control.
Barbed wire & iron fences
“About 2,500 macaques live in close proximity to the people of Lop Buri,” reported Noppawan Bunluesilp for Reuters in August 2009, “scrambling around its famous, ancient Hindu-Buddhist shrine and Khmer-style pagodas, as well as homes and the local market. Barbed wire and iron fences are a common sight on buildings to deter them.
“For years, residents have tolerated the animals, but the monkey population is growing rapidly and intensifying the battle with humans for food and living space.”
In response, Noppawan Bunluesilp said, “At least half of the 1,500 male macaques are expected to be sterilized as part of [a newly initiated population control] program.
“Last year, the primates gave birth to 500 babies. Veterinarians are aiming for a maximum of 300 from now on,” Noppawan Bunluesilp reported.
Momentum not sustained
However, amid local opposition and the political instability then afflicting Thailand, the macaque sterilization program was not sustained.
“The main attraction in Lop Buri is monkeys. The tourists only come here to see monkeys. Only a few of them come here to see the ancient shrine,” temple worker Saksit Saepoo told Noppawan Bunluesilp.
Macaques emerged as an issue across Thailand several years later.
After more than 600 people, including 400 tourists, were bitten or scratched by macaques in and around visitor attractions on the Thai southern peninsula in 2012, “Beware of the monkeys” signs were posted at Long Beach, Monkey Bay and on Phi Phi Island, reducing macaque attacks by about two thirds, Phi Phi Island Hospital director Duangporn Paothong told the Bangkok Post.
Closer to Bangkok, Apilaporn Vechakij of Agence France-Presse reported, “Around 150 households in the shrimp farming community in Chachoengsao province have suffered raids by so-called ‘sea monkeys’ — long-tailed macaques — for about a decade.”
Some linguistic confusion may have been involved in the report, as in the U.S. the term “sea monkey” usually means a brine shrimp.
Eventually then-Thai Department of National Parks, Wildlife & Plant Conservation deputy director-general Theerapat Prayurasiddhi announced “a new plan to manage the dozens of troops of monkeys nationwide, including health checks and identity records,” the Bangkok Post reported.
But the plan was based on the misapprehension that only 500 to 600 macaques in about 50 troops around the entire nation were problematic, most of them around the temple communities of San Phra Kan and Phra Prang Sam Yot in Lop Buri province.
A pilot project was to be “carried out in the mountainous Khao Chakan area of Sara Buri province,” the Bangkok Post said.
Moving “monkey menace” from place to place
What became of that scheme is unclear.
A military coup in May 2014 brought about a complete transition of authority in government.
Two months after the coup, in July 2014, the Bangkok Post announced that, “A study by the Department of National Parks, Wildlife and Plant Conservation concluded that people in 183 areas in 47 provinces were suffering from repeated raids by rascal monkeys,” making the monkey issue more than three times bigger than the estimate of the preceding civilian regime.
But the Thai government response was essentially just to leave “monkey menace” to local authorities. The Lop Buri response was to try to trap and relocate macaques to Department of National Parks, Wildlife & Plant Conservation wildlife care centers in Chachoengsao, Sa Kaeo, Ratchaburi and Nakhon Nayok, which amounted to moving problematic macaque troops from one jurisdiction with macaque overpopulation to another.
Sterilization resumes, on limited scale
Not much was done to advance monkey birth control in Thailand for another several years, though the Parsemus Foundation, based in Berkeley, California, did sponsor a successful trial of an injectable contraceptive called Vasalgel for male rhesus macaques––a species native to northern Thailand––in 2016. Presumably the same product would be effective in the longtailed macaques overrunning cities in southern Thailand, but ANIMALS 24-7 has found no evidence that it or anything similar is being used.
The Thai National Parks, Wildlife & Plant Conservation Department did, however, in August 2019 announce a plan to sterilize 600 long-tailed macaques in the Khao Takiab and Khan Hin Lek Fai hills, surrounding Hua Hin, a fishing and resort city near the top of the neck of the southern peninsula.
Busaba Chokesuchart, vice mayor of Hua Hin municipality, warned that the sterilization program would have to be repeated from time to time to keep the estimated 3,000 macaques forming the local population in check.
Macaques vs. shellfish
Macaques at any time, anywhere, are a prolific and voracious species, much like humans.
“Lydia Luncz at the University of Oxford wanted to investigate the impact of crab-eating macaques on the prey,” recounted Aylin Woodward for New Scientist in 2017. “Her team followed 18 macaques on their daily foraging routes along the shores of Koram and Nom Sao, two neighboring islands off eastern Thailand,” observing how the macaques used stones to crack the shells of the prey species, gradually depleting the prey.
“Tool use, a socially learned behavior, has always been viewed as a positive thing that opens up resources,” Luncz told Woodward. “But by over-harvesting, they put their technology knowledge at risk,” since knowing and remembering how to use stones to crack shells will be of no use to macaques if there are no shellfish left to eat.
Model for human behavior
Anthropologist and evolutionary biologist Nathaniel Dominy, of Dartmouth College in Hanover, New Hampshire, saw in the macaque behavior a model for how modern humans migrated out of Africa more than 70,000 years ago, probably by following coastlines, eating mainly shellfish.
“Over time, we see a reduction in shell size in the archaeological record,” Dominy said, “which suggests a systematic use of shellfish.”
Elaborated Woodward, “Nobody was sure whether size reduction was really due to large-scale human predation, or to changing ocean conditions,” but the Luncz study appears to have answered the question, at least pending the discovery of new evidence.
Dog sterilization progress
Dogs most likely followed modern humans out of Africa, likely just a few steps behind. From then until less than 15 years ago, free-roaming dogs kept the macaque population in check around human settlements, not only in Thailand but in India, Indonesia, Malaysia, China, and every other Southeast Asian nation where macaques are abundant.
The recent success of street dog sterilization programs has almost eliminated canine rabies from the region, and has helped to squelch the dog meat trade, which in Thailand has consisted mainly of illegal exporting dogs to Vietnam and to southern China via Laos.
(See South Korean court rules that killing dogs for meat is illegal, subhead “Help from Thailand.)
After decades of faltering, poorly funded, and ineptly managed government-sponsored street dog sterilization and vaccination campaigns, the nonprofit Soi Dog Foundation, headquartered in Phuket on the southern peninsula, has built an international base of support for a professionally directed effect which has sterilized and vaccinated more than 410,000 dogs against rabies just since the December 2004 Indian Ocean tsunami.
Because the Soi Dog Foundation is an independent nonprofit, not dependent upon government allocations amid perennial conflicts of priorities, it has managed to make unparalleled progress even through the national instability of 2011-2014.
But the success of the Soi Dog Foundation has demonstrated the need for a parallel project to sterilize both longtailed and rhesus macaques, wherever the unaccustomed absence of dogs has left open habitat to the monkeys.
The ecological role of street dogs relative to the macaque habitat niche is threefold.
First, as scavengers, street dogs consume edible refuse. As predators, street dogs hunt the rats and mice who infest the refuse piles and are also consumers of edible waste. In addition, as territorial pack animals, street dogs chase other scavengers and predators out of their habitat.
Dogs chase monkeys & pigs
Monkeys, and street pigs, too, now seldom seen, have traditionally been controlled by the combination of dogs consuming the available food supply and ad hoc dog packs of dogs chasing them, usually formed through impromptu coalitions among dogs feeding from the same food sources.
Macaques, dogs, and pigs are not bitter enemies. Macaques are known to befriend dogs at times, and dogs in turn sometimes adopt and even nurse orphaned macaques. But macaques and dogs are normally territorial rivals, as are street dogs and pigs.
One dog tends to be no match for a troop of macaques or herd of pigs, but several dogs usually prevail.
Now the Southeast Asian street ecology is abruptly changing, especially in Thailand, the “Detroit of Asia,” where automobile manufacturing and use have more than doubled in a decade.
Few dogs left, & fewer pigs, but plenty of garbage
Paved road mileage in Thailand has doubled since 1990, discouraging pigs, who prefer muddy habitats where they can root and wallow. But as refuse collection has often not improved, more food waste is left to scavenge.
Paved roads allow cars and trucks to go faster, posing a greater threat to dogs, who forage in the streets, and not long ago often napped in mid-intersection.
But garbage remains, more abundant than ever as the human population of cities increases, and macaques are quick to seize the opportunity to exploit the garbage, often taking arboreal routes––or routes over electric wires––above the traffic that hits their canine rivals.
(See also Sex, drugs, dogs & monkey business.)