Cha-am, Thailand – Since 14 October 2025, thousands of translucent, bell-shaped jellyfish had been washed ashore along Ban Bo Yai Beach in Cha-am, Phetchaburi province, covering large stretches of sand and alarming tourists and local officials.
Jellyfish carpeted the beach
The unusual scene followed a period of strong winds and rough seas in the Gulf of Thailand, which pushed the animals on to the shore, provincial fisheries officer Prachuab Jiangyee said. “Most of the animals are harmless cup jellyfish (Scyphozoa). They can cause mild skin irritation in sensitive people but are essentially harmless,” he said.
Authorities issued urgent warnings because a dangerous species known locally as “Maengkaprung Fai” — a box jellyfish with long tentacles and vivid colouring — was also reported in the area. Officials said that this species can deliver potentially fatal stings and urged extreme caution.
What to do after contact
Provincial authorities advised beachgoers not to touch stranded jellyfish, even those that appeared harmless. They set out clear first-aid measures for suspected stings: rinse the affected area with seawater, vinegar or lemon juice; avoid using freshwater, which can worsen venom effects; and seek immediate medical help for severe symptoms. Officials also warned laypeople not to attempt to collect or eat jellyfish.
Impact on tourism and outlook
The phenomenon, which typically occurs about once a year when the Gulf of Thailand becomes unsettled, affected the coastline from Ban Laem through Mueang to Cha-am. Cha-am is a popular day-trip destination for Bangkok residents and international visitors, and images of the jellyfish-covered shore circulated widely on social media — some tourists found the spectacle fascinating, others left the beach.
“It is a temporary phenomenon. The beach is not closed, but we advise caution,” provincial authorities said. Experts expected conditions to return to normal within a few days once winds and waves subsided, and urged people to admire the natural display only from a safe distance.