According to a leaked Fisheries Department document, 11 companies exported 230,000 blackchin tilapia fish to 17 countries from 2013 to 2016 before a ban was implemented, raising questions about what may have happened to any leftover stock.
A source in the exotic fish industry who obtained the document said the blackchin tilapia were popular exports as they were both ornamental and edible.
The document shows that 11 Thai-registered companies exported the West African fish, with the biggest exporter selling 162,000 blackchin tilapia overseas during the period.
Other exporters sold between 2,900 to 30,000 fish each during the period.
The source said the data shows that blackchin tilapia in Thailand came from different sources before exports of the fish were banned in 2018.
This has led to questions, the source said, of whether the businesses had exported all of their blackchin tilapia before the ban and what could have happened to any remaining stock, given that the fish found its way to natural waterways in large numbers, threatening native fish and the ecology.
The Agriculture Ministry has called for halting the spread of the invasive species as a national priority, describing the blackchin tilapia as a threat to local biodiversity.
Meanwhile, Sutham Limpanich, a fisheries official, said yesterday that burying the fish is the best way to dispose of them instead of cutting off their heads and throwing them back into the water, as some might hold eggs in their mouths.