Originating from central and south America, suckermouth catfish prey on riverbed life and pose the “ultimate threat” to future generations of freshwater fish, according to volunteer hunter Heidi Shafiq Haidzir.

Shafiq, 37, said river cleaning work is necessary to reduce the suckermouth catfish population, ensuring a balance of freshwater life and protecting the ecosystem.

“Anyone living around Sungai Langat knows that the river used to be full of shark catfish. Ten years ago, if you went fishing in Sungai Langat, you would definitely catch shark catfish.

“These days, casting your nets might net you 20 suckermouth catfish and one other fish like a tinfoil barb (lampam) or tilapia. The shark catfish are more or less gone. We only got one in the evening after six hours. This is terrible,” he said.

Shafiq also said the situation has been hurting the livelihoods of those who get their income from freshwater fish.

He said that protecting the ecosystem is the shared responsibility of all, and that every citizen should have a love for the environment.

“As the nation develops rapidly, so should its environment… not just the economy. Environmental conservation should progress in step, because that is not being seen right now.

“We don’t want a future in which our children will only know these animals in books or pictures,” he said.

Meanwhile, Intan Faraha A Ghani, deputy dean of Universiti Selangor’s engineering and life sciences faculty, said that suckermouth catfish threaten to wipe out other freshwater species as they have few predators and eat the eggs of local fish.

She said that suckermouth catfish largely comprise two genus – hypostomus sp and pterygoplichthys spp – and one fish can produce up to 1,500 eggs, a process that happens several times a year.

“The dominance of these fish is getting worse. In the early 90s and 2000s, only a few (destructive) species were reported in a few places, but now over five species are being found in freshwater, especially around the Klang Valley,” she said.

Intan said that suckermouth catfish also threaten the livelihoods of inland fishermen and native species such as the mahseer (kelah) and hampala barb (sebarau).