For decades, Tham Pha Mak Ho temple in north-east Thailand has been home to crowds of rhesus macaques. Every morning monks feed them with rice and fruit, while tourists give them bananas and seeds bought from the local street vendors.
But over recent months, local people began to notice that when they came with offerings of food, fewer monkeys seemed to greet them. Local media reported claims that hundreds seemed to have disappeared from the temple in Loei province.
Officials are investigating the mystery, said Pracha Saenklang, Wangsaphung district chief officer. It’s possible that changing seasons, or the Covid pandemic, which meant there were fewer tourists bringing fruit, could contribute to the animals migrating elsewhere.
But some fear that trafficking is to blame. Edwin Wiek, founder of Wildlife Friends Foundation of Thailand (WFFT), said the monkeys could have been snatched and transported over the border.
“There are some farms in Laos where we have seen this particular species ending up,” he said.
The trafficking of monkeys, primarily long-tailed macaques, has become a growing concern in the region since Covid. In March 2020, China suspended the export of macaques, disrupting the supply of monkeys to laboratories in the US and creating a shortage that traffickers have sought to exploit, say animal rights experts.
Prior to the pandemic, trafficking of long-tailed macaques wasn’t a significant problem, said Wiek. “The price of long-tailed macaques on the illegal wildlife market was really low – $20 or $30 per piece. I wouldn’t call that a really sustainable kind of wildlife trade. But now the prices went up to five to 10 times more.”
In the US, the cost of lab monkeys rose to between $20,000 and $24,000 in 2023, according to an estimate from the investment bank Evercore reported by the FT in December.
In 2022, habitat loss as well as “unprecedented levels” of hunting and trapping resulted in the status of long-tailed macaques being changed from vulnerable to endangered for the first time by the International Union for Conservation of Nature.
WFFT receives reports of suspected trafficking every two to three weeks.
Lt Col Anek Nakthorn, deputy police superintendent of the environmental crime division, said any locations with monkey populations were considered vulnerable to traffickers, adding that “both tourist attractions and non-tourist attractions, temples with monkeys, are on our watchlist”.
He was aware of at least 10 cases in central Thailand since Covid. CCTV had been installed as a precaution at some sites, he said, and local people, especially street food vendors, could spot people acting suspiciously.
Last week in Nakhon Sawan, in lower northern Thailand, where Anek is based, police arrested two men who were caught using tranquillisers and food bait to try to capture nine monkeys, he said.
Traffickers normally collected fewer than 10 at a time, said Wiek. “[They] then keep these animals in cages or even in bags that they can breathe in for a couple of days until they [have] got the amount of ordered monkeys.” Shipments could range from 50 to 100 monkeys.
The macaques were trafficked across the border, typically to Cambodia, which has been a major supplier of long-tailed macaques to the US.
In November, eight people including a Cambodian wildlife official were arrested in the US and accused of taking macaques from the wild, bringing them to breeding facilities where they were provided false export permits, and then selling them on to laboratories in the US.
‘A type of bio piracy’
The US is clamping down on such crime, according to Dr Lisa Jones-Engel, primatologist and Peta senior science adviser.
This week, Charles River Laboratories, a major supplier of lab monkeys to pharmaceuticals, said it had received a subpoena from the US justice department over an investigation into the supply of primates from Cambodia.
Alongside tougher action against the illegal trade of monkeys, the US has also passed a new law, the FDA Modernization Act 2.0, which removes the requirement for drugs to be tested on animals before they are given to participants in human trials – a breakthrough in the push against animal testing, said Jones-Engel, who predicted it would simply become too expensive for US pharmaceuticals to continue testing on monkeys.
The removal of macaques from the wild not only risked new pandemics, but also was detrimental for the ecosystem and local community, she said. “They are the predators, they’re prey, they’re seed dispersers. They act as buffers to protect human health. And the US is just hoovering them out of the forests of south-east Asia.
“It’s a type of bio piracy and neocolonialism.”
For now, the investigation in Loei continues. In mid-February three people were seen acting suspiciously at the temple. “We had a report that some people came into the temple at night and tried to take the monkeys,” Pracha said.
The individuals, who were reported to the police, were trying to take five monkeys away; two died. “From the investigation those people said that they found the monkeys cute and wanted to adopt them as a pet,” he said, adding it was too early to draw conclusions. Local police were not available for interview.
Numbers, Pracha said, were hard to estimate, given that monkeys go back and forth into the forest.
In Nakhon Sawan, police found nine monkeys taken by the men accused of capturing them through the use of a tranquilliser. One died, while the remaining eight were in the care of the department of national parks until recovered enough to be put back into the wild.
