4 days ago
Authorities, organisers must better monitor release of fish
KUALA LUMPUR: Authorities and fishing competition organisers must better monitor the release and removal of fish in lakes, especially non-native species, to prevent ecological harm.
Universiti Malaysia Terengganu senior research fellow at the Institute of Climate Adaptation and Marine Biotechnology, Professor Datuk Dr Mazlan Abd Ghaffar said organisers should also record the average size of fish released into lakes to identify whether recaptured fish are new or existing ones.
He warned that even enclosed lakes could overflow during heavy rain, allowing invasive species like African catfish (Clarias gariepinus) to escape and disrupt native ecosystems.
"The African catfish is a very hardy catfish species and very aggressive compared to local indigenous fish species, as they pose a greater ecological threat due to their behaviour and rapid growth," he told the New Straits Times.
Once released into rivers, they can outcompete native species, disrupt food chains and take over natural habitats, he added.
"For competitions, organisers must ensure that participants take the fish home and cook them - this would prevent further ecological harm… and ensure that these fish are not discarded back into the river after the competition.
"The Fisheries Department, too, should also monitor the number of fish released and removed, tracking the inflow and outflow accurately," he said.
Asked about the impact of the species entering rivers, Mazlan said these aggressive, fast-growing fish will compete for food and outcompete native species.
He said the risk of them preying on indigenous species is high.
The Fisheries Department has announced that it will draft new regulations to strengthen control activities of fish release into public waters, following complaints regarding the release of African catfish into Malaysia Agro Exposition Park Serdang (Maeps) Lake.
The fish were released in conjunction with a fishing competition organised by the Malaysian Agricultural Research and Development Institute (Mardi) for the Showtech 2025 programme.
The department said the fishing competition's secretariat will install additional hapa nets, provide bins to collect African catfish caught during the competition, and disseminate awareness material while carrying out fishing activities throughout the programme.
Earlier, on May 7, the Fisheries Department had also advised against the release of foreign fish species into public waters without proper consultation, following an incident on May 2 involving a non-governmental organisation releasing fish into a drain at Jalan Lee Sam.
An inspection found that the fish released was also African catfish.
