PATTAYA, Chonburi — Local authorities and fishing communities in Pattaya have raised alarms after a significant number of invasive Blackchin tilapia were discovered along the coastline of the popular resort city, prompting urgent investigations into how a freshwater species has adapted to marine environments and what implications this may hold for the Gulf of Thailand’s delicate ecosystem.

Affected locals dump blackchin tilapia at Government House

The discovery gained widespread public attention after a video posted by “Tart Channel,” a local fishing content creator on YouTube, went viral across social media platforms. The footage showed a cast net pulling up a substantial quantity of Blackchin tilapia instead of the native marine species typically found in Pattaya’s coastal waters. The YouTuber expressed deep concern about the unexpected presence of the invasive fish, questioning how the species has managed to survive in seawater and warning of potential disruptions to the local marine food chain.

“This is not normal,” the content creator stated in the viral video. “Blackchin tilapia are freshwater fish. Seeing them in large numbers in the open sea is alarming. We need to understand how this happened and what it means for our local fisheries.”

In response to the growing concern, fisheries officials from Bang Lamung district conducted an inspection of the area, particularly around the Naklua fish market bridge where the initial sightings were reported. While officials did not observe or capture any Blackchin tilapia during the immediate survey, long-time local residents and fishermen confirmed that this marked the first time in over a decade they had witnessed the species appearing in large schools in open marine waters.

“We are monitoring the situation closely,” said Mayuree Na Phatthalung, a fisheries official from Bang Lamung district. “While we did not see them during today’s inspection, we urge the public and fishermen to remove any Blackchin tilapia they encounter. These fish are safe for human consumption and can be processed into food, but they must never be released back into any waterway, freshwater or marine.”

The Blackchin tilapia, scientifically known as Sarotherodon melanotheron, is native to West and Central Africa and has been introduced to various regions worldwide, often for aquaculture purposes. The species is known for its adaptability to varying salinity levels, which may explain its unexpected appearance in Pattaya’s coastal waters. However, its presence in marine environments raises significant ecological concerns, as invasive species can outcompete native fish for resources, alter habitat structures, and disrupt established food webs.

The Ministry of Agriculture and Cooperatives has ordered an urgent investigation into the incident, with Deputy Minister Watcharaphol Khaokham expressing serious concern regarding the potential threat to local biodiversity and the livelihoods of coastal fishermen who depend on healthy marine ecosystems.

“Invasive species represent one of the most significant challenges to global biodiversity,” Deputy Minister Watcharaphol stated. “We are committed to understanding how this species has entered our marine environment and to taking appropriate measures to protect Thailand’s aquatic resources and the communities that rely on them.”

Marine biologists note that the appearance of freshwater or brackish-water species in fully marine environments is unusual and warrants scientific investigation. Factors that may contribute to such occurrences include accidental releases from aquaculture facilities, escape from ornamental fish trade operations, or natural adaptation driven by environmental changes.

“The ability of Blackchin tilapia to tolerate a wide range of salinities is well-documented, but their establishment in open marine waters would be a significant ecological development,” said a Bangkok-based marine ecologist who requested anonymity. “We need comprehensive surveys to determine the extent of their presence and to assess potential impacts on native species.”

For Pattaya’s fishing communities, the discovery has prompted both concern and practical responses. Local fishermen have been advised to report sightings of the invasive species and to avoid releasing any captured Blackchin tilapia back into the water. Some have begun documenting their catches more carefully to help authorities track the spread of the species.

Invasive fish species spotted off Pattaya beach https://t.co/cQCyiORuA4 @TNAMCOT pic.twitter.com/ZUDKkAGEmH

— TNAMCOT English (@TNAMCOTEnglish) May 14, 2026

“We’ve been fishing these waters for generations,” said one Naklua-based fisherman who requested anonymity. “We know what belongs here and what doesn’t. Seeing fish that shouldn’t be here is worrying. We hope the authorities can figure out what’s happening and how to address it.”

The Department of Fisheries has indicated that it will coordinate with academic institutions and research organizations to conduct more extensive surveys of Pattaya’s coastal waters. Sampling efforts will aim to determine the population size of Blackchin tilapia, assess their reproductive status, and evaluate potential pathways of introduction.

Public education campaigns are also being considered to raise awareness about invasive species and to encourage responsible behavior among aquaculture operators, aquarium enthusiasts, and the general public. Releasing non-native species into natural waterways, whether intentionally or accidentally, remains a primary vector for biological invasions worldwide.

“Prevention is always more effective than remediation,” noted a representative from a Thai environmental conservation organization. “Once an invasive species becomes established, eradication is extremely difficult and costly. Public awareness and responsible practices are our best defenses.”

For tourists visiting Pattaya, the incident serves as a reminder of the environmental challenges facing popular coastal destinations. While the presence of Blackchin tilapia is not expected to pose direct risks to beachgoers, the broader implications for marine health and fisheries sustainability underscore the importance of supporting conservation efforts and sustainable tourism practices.

As investigations continue, authorities have appealed to fishermen, researchers, and members of the public to report any sightings of Blackchin tilapia or other unusual species in Pattaya’s waters. Documentation including photographs, location details, and catch information can provide valuable data for scientific assessment and management planning.

Vietnamese man caught smuggling endangered species in Sa Kaeo

The Ministry of Agriculture and Cooperatives has committed to providing regular updates on the investigation and to coordinating with regional partners in Southeast Asia, where invasive species management is an increasingly shared challenge. Further announcements regarding survey results, policy responses, and public guidance are expected as the situation develops.

-Thailand News (TN)