A freshwater fish species from South America, released into our rivers by fish breeders and aquarists, may pose a threat to local fish species and the ecosystem.
Thankfully, it’s not the dreaded man-eating piranha. The fish is popularly known in the fish hobbyist circle as ikan bandaraya because it does a good job cleaning up fish ponds and aquariums off algae and sediment.
The bad news is, once these fish have performed their ‘duty’, they are unceremoniously chucked into drains or rivers. The ikan bandaraya has a habit of burrowing into the ground or river banks, sometimes a few feet deep, to lay eggs. Their burrowing weakens the riverbanks and contributes to erosion.
But not many aquarists in the city are aware of this fact. Sungai Klang is said to be one the favourite dumping grounds where ikan bandaraya of various sub-species and sizes can be found.
Common ikan bandaraya species found in Malaysian households include the H. plecostomus (sucker mouth) or leporacanthicus galaxies (vampire plec). This is in addition to several other species of dotted or spotted sucker fish variety.
Exotic fish shop owner Michael Teng said the ikan bandaraya were imported mainly from South American countries and were popular among goldfish owners. He said the young scavenger fish, usually about the length of our index finger, were priced between RM1.50 and RM2 each.
“Ikan bandaraya tends to grow fast due to its huge appetite. It tends to eat any waste and algae found in an aquarium or tank.”
“It has a reputation for biting other fish once it grows bigger. There have been cases where the normal seven to eight centimetre-long ikan bandaraya can grow up to two-feet long over several months.”
“This is why owners usually keep it for about three months before disposing of the fish in nearby drains or lakes,” said Teng, the owner of Pudu Aquarium in Jalan Pudu, Kuala Lumpur.
Exotic fish collector Adrian Koh of Damansara Utama said the dumping of ikan bandaraya in lakes and drains was normal practice among aquarium owners. The 29-year-old sales executive said the fish had long established itself as the most common of scavenger fish among local aquarists due to its affordability and adaptability to a variety of water conditions.
“All aquarists from novices to experienced fish keepers have at one time or another kept this fish.
“The ikan bandaraya is ugly and grows quite big after a while. So, why should I keep it among my Japanese Koi and goldfish?” he asked.
Koh said the ikan bandaraya would grow quite big after three to four months and would then start attacking the goldfish or the other fish in his aquarium.
“That’s when the problem starts. So, I dump them once they have done their ‘job’ and before they attack my prized fish,” he said.
A check with the Federal Territory Drainage and Irrigation Department (DID) and City Hall found that both authorities have yet to carry out any research on the ikan bandaraya, which can be found in the main rivers and tributaries in the Klang Valley. FT DID senior assistant director C. Poobalan said he could not recall any efforts carried out by the department to remove the species from the rivers in the past years.
A spokesman from City Hall’s drainage and irrigation department said eliminating fish species was not under its jurisdiction as its main job was to ensure rivers and tributaries as well as their banks were free of rubbish and sediments.
It is learnt that City Hall had not released any of the so-called ikan bandaraya fish into the rivers in Kuala Lumpur to clean up the rivers. While there seem to be no proper studies done on the fish population in Sungai Klang and Sungai Gombak, the Petaling Jaya-based Global Environment Centre (GEC) has studied the fish in the lakes in the Kelana Jaya recreational park and Taman Aman in Petaling Jaya.
GEC programme officer Dr Kalithasan Kailasam said a study conducted with the Malaysian Anglers Association in March 2002 found that 95% of the fish in the Kelana Jaya lake was nonindigenous, including the sucker fish (ikan bandaraya), flower horn, tilapia, blue catfish and guppy.
“The ikan bandaraya does not create any problems to other fish but it digs holes in the riverbed or lake, sometimes a few feet deep and long, to lay eggs in.”
“Once it starts digging, the foundation of the river banks will be jeopardised,” he said, adding that a separate study at Taman Aman found that 70% of the fish there were foreign species.
Dr Kalithasan said the presence of alien fish might not cause serious danger to local ones but the latter would lose out to the hardy foreign breeds that were known for their better survival rate in the ecosystem.
“Local fish should remain dominant in our lakes and rivers,” he said. Dr Kalithasan blamed the public for releasing the ikan bandaraya into the lakes and rivers. He said he had received a number of calls from the public who sought the centre’s advice on
whether they could throw the fish into the Kelana Jaya lake.
“We will propose to the Petaling Jaya Municipal Council to turn one of the lakes in the municipality into a dumping lake for “alien” fish.” he said. GEC has been involved in the rehabilitation of Kelana Jaya and Taman Aman lakes and awareness campaigns in schools.
The programmes are funded by the Danish International Development Agency (DANIDA) and United Nations Development Programme-Global Environment Foundation Small Grant Fund. Besides the ikan bandaraya, other creatures have also been spotted in Sungai Klang.
For example, four crocodiles were sighted last Friday. However, the Wildlife and National Parks Department assured city residents that these reptiles would not pose a danger.
The popular freshwater Tilapia, which is of African origin, is also found in the Klang River. Tilapia that escapes from aquaculture facilities in Malaysia pose the risk of reducing food supply, native habitat, and spawning areas for native fish species. Despite pollution, the river still attracts river turtles, monitor lizards and scavenger birds. The water monitor lizards are still common in Malaysia despite the tremendous development that has taken place in the last 30 years.