Will Monkeys Become Britain's New Big Cats?
A rational look at the looming risk of loose primates in post-licensing Britain
There’s something quintessentially British about the big cat story. The panther on the moors, the dog walker who swears blind they got stalked, paw prints in the mud, the dead sheep with curious tooth marks - always out of reach, always just missed by a blurry iPhone camera. For decades, sightings of mysterious felines roaming the UK countryside have captured the public imagination. Ask anyone with a leaning towards the unexplained, and you’ll quickly hear a theory: these animals were once pets, released into the wild when regulations tightened in the 1970s, giving rise to the folklore and files of the “British big cat” phenomenon.
Now, another change in animal-keeping legislation is on the horizon - and another set of creatures may be at risk of taking to the hedgerows.
From April 2026, it will become illegal to keep a primate - any monkey, lemur, or similar species - as a pet in England without a license. The new rules, part of the Animal Welfare (Primate Licences) (England) Regulations 2024, require that owners not only register their animals but meet strict zoo-level welfare standards. Primates must be kept in appropriate social groups, housed in enriched environments, fed a suitable diet, and inspected by vets. In effect, the law raises the bar so high that most traditional pet ownership of monkeys will likely come to an end - or at least become significantly rarer.
That, according to campaigners, is a good thing. Reports like the RSPCA’s Do You Give a Monkey’s? found that the majority of pet primates investigated were kept alone, which is a fundamental cruelty for species that rely on social bonds to stay well. Others were found malnourished, kept in bird cages, suffering from rickets, or exhibiting clear signs of stress and trauma.
But the law, well-intentioned as it may be, raises an uncomfortable question for those of us with an interest in animals out of place… what happens when the owners of these animals can’t - or won’t - comply?
Is it unreasonable to wonder whether we’ll soon be seeing reports of monkeys in the woods, lemurs on lampposts, or capuchins clambering around allotments?
A Rational Lens on an Irrational Image
At first glance, the idea of monkeys roaming the British countryside seems absurd. And to be clear: I’m not suggesting we’re on the cusp of a baboon invasion. But Britain already has a long history of anomalous animal sightings - wallabies, racoons, raccoon dogs, lynx, and yes, monkeys.
There’s a particular logic to the monkey question. We know private ownership of primates is currently legal, and that existing keepers will soon need to meet far stricter standards. We also know that many of these animals are kept in low-welfare settings. If owners cannot afford the enclosures, enrichment, or vet care required, they may be faced with a choice: surrender the animal, keep it illegally, or get rid of it in other ways.
Historically, the tightening of animal ownership laws has sometimes had unintended consequences. After the Dangerous Wild Animals Act 1976 came into force, a number of exotic pets - including big cats - are believed to have been released into the wild rather than handed over.
Though the majority of Big Cat sightings in the UK are unlikely to actually be felids, there are occasional sightings which are exactly that. For example, in the 1980s, a tame puma, later named Felicity, was caught by a farmer in Scotland. It is believed that she was released into the wild by her owner (just a few years after the 1976 act was introduced.) In 2001 keepers from London Zoo captured a Lynx from a house garden in London.
Elsewhere, in 2002 and 2005, forest rangers conducting a deer survey in the Forest of Dean caught two big cats on camera. And more recently, in 2025, four lynx that were illegally released in the Highlands were successfully captured, and three of them rehomed.
With this in mind, monkey’s in the wild suddenly doesn’t seem so ridiculous. It’s not hard to imagine that, come 2026, a handful of pet primates might quietly disappear from domestic settings without being rehomed through official channels.
And that’s where things get fuzzy...
Escaped? Abandoned? Or Just Moved On?
In recent years, there have been several confirmed cases of pet primates being found out of place. In 2024, a marmoset - a small South American monkey - turned up in someone’s conservatory in Wolverhampton. The animal was suffering from rickets and had part of its tail missing, suggesting it hadn’t exactly come from a well-managed habitat.
In other cases, primates have been found dead by roadsides, presumed to be escaped or abandoned pets. Some are handed in to sanctuaries like Monkey World in Dorset, which has long campaigned for stricter regulation of the pet primate trade.
None of these incidents involved large numbers. But that’s not the point. Britain’s big cat stories didn’t start with a pride on the loose - they started with odd sightings here and there. One person sees something strange on a country lane; another finds tracks on their farm, sheep start turning up dead, and suddenly the Royal Marines are being sent into the Exmoor hills with sniper rifles (yes, that really happened.)
It doesn’t take a population to create a phenomenon, just enough uncertainty and suggestion. A monkey in a tree, spotted from a passing train. A blurred video shared on TikTok. An unfamiliar silhouette glimpsed at dusk. From there, the myth takes hold.
The upcoming changes to primate ownership law are significant. From April 2025, current owners have been able to apply for licenses. From April 2026, it becomes illegal to keep primates without one. Councils will oversee inspections, issue licenses, and monitor conditions. But enforcement - especially for those who choose to slip under the radar - may prove challenging. Some owners may simply let their animals go.
The RSPCA has already raised concerns about this possibility, warning that without clear rehoming pathways and public education, “monkeys could be abandoned, dumped or turfed out onto the streets.”
How Likely Is a Monkey Boom?
Let’s temper the speculation with some facts. Most of the monkeys kept as pets in the UK are small, tropical species like marmosets, tamarins, and squirrel monkeys. These animals are not adapted to the British climate. They are social, sensitive, and unlikely to survive long in the wild - especially in isolation. Even if a handful are released, they likely will not thrive or reproduce, and the chance of a roaming colony establishing itself in rural England is slim to none.
But that doesn’t mean sightings won’t happen.
Much like with big cats, even rare incidents can fuel decades of speculation. A primate out of place is a powerful image - uncanny, cartoonish, and just believable enough to grip the public imagination. And unlike big cats, which generally keep to themselves, a monkey is more likely to interact with human spaces - gardens, roofs, fences. The spectacle of it makes it newsworthy which could feed into a cycle of false sightings and social media hype.
In this sense, the monkeys–big cats comparison works best as a cultural one. We are not facing an ecological threat from feral primates, but we may be on the cusp of a new chapter in British anomalous animal folklore. A shift in what’s considered “unbelievable but possible.” Where once we imagined pumas, now we may imagine capuchins.
What Comes Next?
As someone who keeps a close eye on reports of cryptids, out-of-place animals, and the blurry boundary between folklore and fact, I’ll be watching the transition period carefully. The deadline is now just months away. As the law kicks in, rescue centres may fill up. Some primates may quietly vanish. A few may find themselves somewhere new - not quite wild, but not quite domestic either.
Whether or not we end up with “monkeys on the loose,” what’s certain is that we’re about to see the end of an era - one in which it was easier to buy a monkey than to register a dog. What replaces it may not be a jungle in the Cotswolds, but it might just be a rash of reports that leave us asking… did you see that?