According to reporting in The Hindu, the warning specifically mentions Clarias Gariepinus, a popular catfish species. Producers have been culturing the fish in local waterbodies, but poor biosecurity measures have led to some catfish escaping the farm environment. Though breeding and raising the species has previously been banned, some fish farms have maintained stocks.
Animal health authorities in Tamil Nadu say that the catfish are invasive, and escapees from inland fish farms pose a threat to the survival of native fish species and the surrounding environment. Farmers are being advised to destroy any catfish they have bred.