‘Ikan Bandaraya’ – from aquarium to aggression

Part time fishmonger, Rahman Alai 55 yrs old showing the "ikan bandaraya" that his catch during fishing at Sungai Damansara near the Selangor shooting Association shooting range in Subang on October 25 for story on foreigner species fishes that attack other in the fishery are in danger.—AZMAN GHANI/The Star

PETALING JAYA: The popular ikan bandaraya, or suckermouth catfish, is sought after among hobbyists for its ability to clean fish ponds and aquariums of algae and sediment.

However, they are also often dumped into drains or rivers when they grow too big for aquariums.

That leads to the problem of these invasive fish destabilising riverbanks and causing erosion due to their aggressive burrowing behaviour, says an expert researcher.

“As these fish dig extensive networks of tunnels and cavities, they significantly disrupt sediment stability, particularly in riparian zones,” Universiti Sains Malaysia Engineering Campus’ River Engineering and Urban Drainage Research Centre (REDAC) deputy director Dr Chang Chun Kiat said yesterday.

“The burrowing not only loosens riverbank soil, heightening erosion risk, altering riverbeds, disrupting natural flow and reducing biodiversity by outcompeting native species for resources.“It threatens critical infrastructure near rivers by destabilising banks and compromising the integrity of bridges, embankments and flood controls,” he said.Chang recommended several strategies to mitigate erosion and sedimentation from suckermouth catfish, including reinforcing riverbanks with armour rock or materials to prevent burrowing.

“Boost native herbivorous species through stocking programmes to restore ecosystems and outcompete invasive fish. Conduct organised removal initiatives, like Selangor’s ikan bandaraya hunting campaign, to control fish populations.

“We can also install control structures to isolate infested areas and prevent the spread of invasive fish,” he said.

Chang also called on the Fisheries Department to collaborate with NGOs like Ikan Bandaraya Hunters and River Monster Hunters, and organise social media campaigns to highlight the need for collective action.

“Encouraging local fish for ornamental, recreational and aquaculture purposes can reduce dependency on alien species, benefiting both our ecosystems and our communities,” he added.

Environmental pollution engineer Loi Hang Kuang said rock bunds and concrete walls are solutions to stop bank erosion.

“While rock bund is a cheaper option, the concrete wall has a better resistance to erosion,” he said.

Loi also said mangrove trees are important to keep erosion at bay as well as creating a safe habitat for many wildlife species.

Preservation and replanting of the vegetation along riverbanks is also one of the best and most natural ways to protect the riverbanks, he added.