Living and breathing

Caring for the biodiversity of our rivers

Text by Nadiah Abdul Aziz
Photographs by Mahen Bala

“You could not step twice into the same river; for other waters are ever flowing on to you.”

This famous quote from the words of an ancient Greek philosopher refers to his doctrine of change being central to the workings of the universe, but applies equally well when describing the living ecosystem of a river. The ecology of running waters are dependent on many things, one of which is the state of continuous physical change.

“To make sure there is life in a river, we need to achieve equilibrium. Everything in the river and its surrounding must reach a balance,” says Universiti Kebangsaan Malaysia Associate Professor Dr Ahmad Abas Kutty. “It’s hard to explain. Ecology is difficult,” he continues. “You need to integrate so many elements. A river must have the perfect balance of everything, before anything will live in it.”

Understanding what happens around, as well as inside our rivers is equally important in formulating informed, sustainable policies in river management.

In Malaysia, the source of most rivers are thriving and healthy. Many of these areas register Class I or Class II in terms of water quality, indicating that all is well and good upstream. Where there is human contact is where the problems start. The biggest threat to rivers is the habit of sealing the riverbanks with concrete, a common way to “tame” a river to pave the way for development. Changing the slow and meandering flow to a single channel makes the river prone to flash flooding when there is an excess of rainwater, a clear sign of poor river management in cities.

This urbanising or channelising also inadvertently alters the path of rivers, which should follow their own twists and turns through the natural landscape. With nothing to stop the rapid flow of water, there are no nooks and crannies in which leaf litter can accumulate, and decompose organically. This is a crucial part of ensuring a thriving river ecosystem. “The good news is you can rehabilitate,” says Monash University Malaysia Associate Professor Catherine Yule, tapping the tip of her pen on pictures of Sungai Ampang. “With plants and a gravel riverbed, it is obviously healthier. Because of vegetation and a natural bottom instead of concrete, animals can live here and have food to eat.”

Even in the most trying circumstances, life will always find a way to prevail, but only if we give it a chance. These two otters were recently spotted on the banks of Sungai Kerayong in Ampang.

“When it’s just concrete, everything just goes whoosh! Animals can't live there if everything is just washed away,” she continues. “So you need to replant the native vegetation for the animals, and add big rocks on top of the concrete. Then you have both fast and slow flow of water.” But perhaps the most important function of river flow, is to saturate the water with oxygen in a process called aeration. Only then will rivers contain oxygen levels needed to sustain life.

This brings the question back to the balance of all the elements. Left on its own, nature will do its work and the river will thrive. “Humans. We are the problem,” says Dr Ahmad Abas Kutty. There’s a pregnant pause after that statement, punctuated only by the drone of the water filter attached to his office aquarium. “What we need to achieve is Class IIb. That is the minimum that we need for a river to sustain life.” he continued, lamenting the fact that pollution is entirely man-made.

A young boy is seen adjusting his self-made spear gun, after spotting some lampam and tilapia in the upper reaches of Klang River.

The other issue, is overfishing, a global phenomenon already affecting the oceans and seas. He tells of villagers in rural areas who are willing to use electric shockers to catch a mere handful of fish, without a care for the dozens others left behind for dead. In the city, there are also migrant workers, documented or otherwise, who are so hard-pressed to survive that they resort to poisoning the river in order to catch a meal.

The question is, can anything be done? Dr Ahmad Abas Kutty gives the example of the great river rescues of Europe and elsewhere in the world. At the same time, there are success stories locally, such as Sabah’s tagal, a community-based initiative where villagers serve as caretakers of their local rivers, with tightly-controlled fishing schedules to protect the ecosystem. The project has been expanded to hundreds of rivers in the state.

“It doesn’t take long for a population to recover. Plants don’t take a long time to grow, just a few months,” he says. “Create the ecosystem and achieve the balance; ensure water quality and clean up its surroundings. Be rid of the invasive species and reintroduce the native fish, then prevent human disturbance to the population at least for one year. Then the rivers will come back to life.”