Over the last several years, Bangkok has become a focal point of the Asian Water Monitor Lizard (Varanus salvator) trade. This dinosaur-like giant is the world’s second largest lizard, reaching lengths of up to two metres (7 feet). This astounding animal thrives in the city’s sprawling system of khlongs, or canals. It has made a splashy debut in sought-after locations such as Lumphini Park. More than 400 Asian Water Monitor Lizards call the park home. They are rapidly becoming a new icon of the resilience and adaptability of Bangkok’s urban wildlife.
The Asian Water Monitor Lizard lives in rivers, lakes, and swamps across Southeast Asia. Its range even reaches north into India and China. In the city of Bangkok, these lizards have a constant all-you-can-eat seafood-and-chicken restaurant, gobbling up fish, birds, chickens, and leftover organic waste. They are integral to our marine ecosystem. By removing animal carcasses and keeping rat infestations in check, they are important, if unseen, players in the urban ecosystem.
The growing invasion of these lizards has made officials at Florida Fish and Wildlife Conservation Commission very worried. In a perfect world, the human population in Lumphini Park would stay under 400 to avoid ecological and humanitarian disaster. In 2016, wildlife officials rounded up dozens of Asian Water Monitor Lizards and removed them from the park. They moved these reptiles to combat overcrowding issues. The female lizards can further increase their numbers quickly, as they lay large clutches of around 20 eggs at once.
The allure of these lizards doesn’t end with their ecological importance. They’ve held a global fascination. A viral video from 2021 showcased one climbing a convenience store shelf, further fueling interest and drawing visitors to Lumphini Park. This surprising phenomenon is fueling a positive viral trend across platforms such as TikTok and Instagram. Already, folks are posting and tweeting their experiences with these “monsters.”
“When you’re in [Thailand], you have to come to Lumphini Park to see these monsters!” – Jayla Chintanaroj
Though the arrival of these lizards brings some edgy character to the city, they bring with them dangerous hazards. Thosapol Suparee highlighted safety concerns, noting that “on roads, water monitors may pose risks for accidents.” Additionally, the lizards experience “fear and disturbance during rest or exercise,” which may impact their well-being.
The Thai government has acknowledged both the rising populations and commercial opportunities Asian Water Monitor Lizards can offer. To that end, they have begun permitting limited breeding of such lizards for use in commercially-made products—including leather goods. With this decision, we hope to reinforce the private sector and alleviate communities beset by lizard skirmishes. It is intended to reduce the incentive for illegal hunting and mitigate negative impact on wild populations. So far this year, permits have been issued for more than 200 lizards.
“We think this decision will benefit the private sector and communities with conflicts, as well as reduce illegal hunting and the impact to water monitors in the wild,” – Somying Thunhikorn
Urban wildlife is absolutely booming in Bangkok! Scientists are calling for the public to focus more on misunderstood reptiles like the Asian Water Monitor Lizard. Álvaro Luna, co-author of a 2024 study, noted that “despite being one of the largest lizards with established populations in urban areas, Varanus salvator has drawn relatively little attention from ecologists regarding its colonisation of numerous major cities across Asia.” He emphasized that “sometimes these ecological or zoological phenomena are very obvious in urban areas, yet they still don’t get enough research.”
The introduction of these lizards has lead to even more creative steps, to help publicize their importance in Bangkok’s ecosystem. Recent installation serves to remind us that water monitors are not just park creatures. As beloved local fixtures, they represent the vibrancy and diversity of the city’s natural environment.
“It was erected to show that water monitors are not just park animals, but also represent the richness of Bangkok’s ecosystem,” – Thosapol Suparee
Visitors have penned their stories of close encounters with these magnificent creatures, recounting experiences filled with wonder. JX Ang remarked on an experience saying, “It was like a massive lizard onsen Jacuzzi. It was awesome.” Potential human interactions Observers have described the surprisingly large and intimidating lizards as quite harmless. Jayla Chintanaroj commented, “The big ones are usually fine because they move quite slowly and you can kind of hop over.”