Published On 13 Nov 2025
An invasive fish is threatening livelihoods in a northwestern Sri Lankan village by devouring traditional fish and shellfish species in the Deduru Oya reservoir, but local fishers aim to transform this challenge into an opportunity.
Over the past two years, fishermen have observed declining numbers of their typical catch while snakehead fish, previously unseen in Sri Lanka, have appeared in abundance.
According to local officials, the snakehead fish, common in Thailand and Indonesia, likely arrived with imported ornamental fish. When they outgrew home aquariums, owners probably released them into the reservoir.
Dr Kelum Wijenayake, a researcher studying the fish, explained that snakeheads have no natural predators in Sri Lanka’s ecosystem. “The Deduru Oya reservoir has provided them with an ideal breeding ground with ample food and no predator,” he said.
These fish can surface to breathe air and survive with minimal water. Their sharp teeth, powerful jaws, and aggressive feeding habits threaten the local ecosystem that has evolved over thousa