The Agriculture Ministry has vowed to make the eradication of blackchin tilapia fish a national priority, saying methods to prevent this invasive species from breeding are being studied.
Minister Thammanat Prompow on Tuesday said his ministry has been working to get rid of the invasive species that are native to West Africa because they are predators and pose a great risk to underwater biodiversity.
Related agencies have been asked to study whether sterilisation would affect the fish's chromosomes and lead to a mutation of the species.
Capt Thammanat said this was a serious matter that required thorough research, so, for now, it is necessary to get rid of them.
The Rubber Authority of Thailand (RAOT) was also told to establish a fund to buy the fish as fertiliser for rubber plantations, he said.
Capt Thammanat said it was unclear when and how blackchin tilapia arrived in Thailand; however, the ministry has been working on catching the fish in many provinces for a long time.
He said that unless there is permission from the authorities, bringing this particular species into the country is illegal.
Premsak Wanatsunthorn, Deputy Managing Director of Fish Research and Breeding for CP Food (CPF), said that the company is not linked to the blackchin tilapia that are spreading.
The company eradicated all the blackchin tilapia it had in stock in 2011.
He said the company had lawfully imported 2,000 of the fish for research purposes in 2010. However, only 600 initially survived and were under Fisheries Department observation.
The number later dropped to 50 due to their poor health condition. The company then decided to stop the research and kill the fish using chlorine in January 2011.
Mr Premsak also said that Fishery Department officials had investigated CPF's fish farm in Samut Prakarn when it was discovered the species was spreading in waterways in 2017.
Bangkok governor Chadchart Sittipunt uploaded a video stream on his Facebook page on Tuesday showing blackchin tilapia being cooked, suggesting that the fish could be turned into several delicious dishes.
On Monday, people were seen catching the fish in many areas of Bangkok, including Makkasan Pond. Most said they would eat them, a source said.
The source also said the Samut Sakhon Fisheries Office had introduced measures to encourage people to catch them.
The office also offered to buy the fish from locals at eight baht per kilogramme and would resell them to fishmeal plants in the area.
