By Tay Jing Xuan (20S03C) and Ng Jing Ting (20A13A)
Special thanks to Raffles Science Institute and Mrs Christina Khoo
It’s the same dreary routine every morning—half-asleep, you walk through Marymount Gate, and follow the sluggish crowd of students trailing downtown to the parade square. And before you know it—golly gee! You’ve walked right past the Biodiversity Pond (or, in the fabled case of an unfortunate student, right into it). If you’d opened your eyes a little wider amid your sleepy haze, you might have noted the understated beauty of its ecosystem. But perhaps you don’t, and instead you glance at the pond and snicker at the half-faded sign that heralds the “testicle-eating” pacu, note the scraps of soaked bread floating on its surface, and proceed to forget about the whole scene altogether.
Few actually stop to wonder—exactly what goes on in and around the pond, besides catfish glancing the surface from time to time and mosquitoes flitting about the boardwalk? Raffles Press is here to fill you in on those questions, with the help of a few dedicated individuals, including the pond’s very own caretaker, Mr Lim Bah Hock.
What’s in a Pond?
The Raffles Biodiversity Pond was built in 2009 under the Turnkey Project, its design having taken two years to be conceptualised and finalised. Several external partners were consulted on the selection of fish and plants to be displayed, including Wildlife Reserves Singapore. When one thinks about a pond, vivid images of koi and other such ornamental fish come to mind; however, in this case, the intention of the pond was, according to the Raffles Science Institute website, “to showcase flora and fauna from Southeast Asia”, allowing students to learn about ecology and biodiversity outside their curriculum. Hence, the pond serves a didactical purpose in addition to its aesthetic one. And it has served it well—in 2010, the Biodiversity Pond received a silver award from the Landscape Industry Association of Singapore (LIAS) in recognition of its outstanding design.
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Upon approaching the pond, one would immediately spot a bench. It has offered its companionship to numerous students over the years, and during school hours it’s nearly never devoid of occupants. In fact, the sheer volume of students that interact with this sturdy block of wood on a daily basis begs the following question—why, then, has the pond’s information guide, situated right next to the bench, remained perennially untouched, the thick layer of dust enveloping the pages of the tome bearing testament to the fact that its pages have been left virtually unturned for the better half of the decade? The plastic casing of the laminated pages, which promise to inform the reader about the various types of Southeast Asian freshwater fish, have yellowed over time as well, giving rise to its rather unappealing appearance. And, indeed, paralleling the collective neglect of the information guide, the queer looks shot towards us throughout the afternoon were reflective of how rare of an occurrence it was that the pond would be paid such an inordinate amount of attention by any member of the student body.
For those who do spare the pond more than a passing glance, however, the first things they might notice about the pond while dropping by at any given time are the slick, black noses of large fish surfacing to take in air. At first glance, one might think they belong to humongous catfish. A closer inspection would reveal them to be those of their shark catfish cousins, the iridescent sharks, Pangasius hypophthalmus. Gentle giants, the iridescent sharks’ diet consists of plant matter and other smaller fish, which does not harm any of the ponds’ residents as the sharks receive daily feed. They might be rather big, but, truth be told, they are dwarfed in both size and aggression by larger fish in the pond, like the gourami or the pacu.
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Many collectors pride themselves on getting their hands on the Asian arowana, believing it to bring good fortune to their owners. We should, too, for in our very own pond resides the Asian arowana, Scleropages formosus. Although a popular aquarium fish in Asia, it is an endangered species due to its overfishing and the massive demand for it in the Asian market, compounded by the fact that the arowana only breeds once a year. There have been valiant efforts to conserve the Asian arowana, such as labelling it as a protected species under the Washington Convention, an international agreement that safeguards the survival of animal and plant species from trade activities and their impacts. Even Singapore has joined the fight against its extinction—it has started arowana farms to reduce the overfishing load on arowana in the wild.
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The waters of the pond may hold some truly remarkable fish, but what about the plants that line its perimeters? Clusters of the dwarf papyrus, the Cyperus papyrus, among other plant species, have eagerly made their homes in our very own Biodiversity Pond. The dwarf papyrus does not originate from Southeast Asia, but hails instead from Africa. Egyptians used the plant to manufacture not just the popular papyrus paper, but also handy items such as boats, sandals, baskets, and more. With its versatile utility, it can be considered the wood of the past. Now, it is largely used as decoration, not just in African households, but also in gardens and ponds all around the world, brightening the dullest landscapes with its lush, green clusters.
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Regular avian visitors, such as the striated heron, Butorides striata are frequently spotted around the pond as well. The striated heron adheres to a carnivorous diet, snapping up fish from the pond when it finds an opportunity to strike and contenting itself with insects that live among the plants. Its irregular visits often prompt a large gathering of students intent on capturing its image on their mobile phones. (Tip: if you’re inclined to do so as well, 6.30pm is prime time to be there.)
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And these are just the tip of the iceberg where the pond’s flora and fauna are concerned. For the full list of fish, as well as details about the background of the pond, you can visit this page.
The Pond’s Trusty Caretaker
Mr Lim has worked here for almost nine years. He hasn’t always been the pond’s caretaker, though—he had been in charge of tending to the flora and occasional fauna (both friendly and hostile: think wasps and bats) before he was reassigned to the pond. As the sole caretaker of the pond now, he tells us in Mandarin that although he wasn’t trained with aquatic life care, he still feels a connection towards the fishes.
He may appear to speak nonchalantly, claiming that he sees taking care of the fish as merely “feeding them”, but it is evident that, deep in his heart, he truly cares about the pond. He shows us picture after picture of dead fish on his phone, recollecting the times when fiercer fish would engage in vicious fights over the fry he would buy for them. “Even fish and humans have a bond,” he says dolefully, pausing at a picture of one of the white koi which had passed away and which then had to be scooped out of the water. “When they die after we’ve taken care of them for so long, I feel sad too, you know?”
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Walking past the biodiversity pond in the morning, one would be apt to spot a few curious objects floating on the surface of the main display pond. Those rectangular-shaped oddities turn out to be whole pieces of bread that Mr Lim periodically flings into the pond throughout the day as food for the fishes. In the same way allowing carbohydrates to saturate one’s diet spells a medical disaster for the human body, fish were likely to develop health issues were they to do so as well. Hence, Mr Lim went ahead and bought fresh vegetables with his own hard-earned money, intent on keeping his beloved fish alive and healthy for a rather more extended period of time. “Of course, I could get leftover vegetables from the canteen,” Mr Lim says off-handedly, “but I couldn’t bear to let the fish eat rotten food. If people don’t want them, neither would the fish.”
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A kingfisher (perhaps three, we aren’t very sure) has been spotted from time to time, diving for the fish in the pond and gulping them down every day. When asked about whether he was concerned about dwindling numbers of fish, Mr Lim simply laughs. “There are so many fish! It can’t eat all of them, even if it wanted to. All of the fish breed quickly.”
He points at the three terrapins swimming leisurely through the water. “There didn’t use to be so many fish when this pond was built,” he adds. “But after getting tired of taking care of [them], students like to dump their pets here, like the terrapins there.” This has led to the sharp increase in the number of fish in the pond—there is no corner of the pond that is underpopulated, nor will anyone ever get bored staring at the diversity in the waters.
The Tilapia Problem
While the pond might be bustling with life and activity, some of the fish that were once in the pond have now ceased to be. In addition, due to some indiscretion over the years, a few tilapias were released into the pond, where they quickly multiplied and now reside in hundreds. And the numbers are still climbing.
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Because of their hardiness and the difficulty in controlling the rate at which they breed, tilapias proliferate throughout the entire pond. As a result of their large numbers, the tilapias now pose a hazard to the rest of the pond due to the large amounts of nitrogenous waste they release, putting much pressure on the filtering systems of the pond. On top of that, they compete with the native fish for resources, further endangering the fishes’ lives and putting them at risk for disease. Unable to withstand the pollution and limited food and space, some species have even entirely disappeared from the pond for good.
Raffles Press would thus like to remind everyone to think twice before releasing exotic species into the school pond. While it might be enticing to introduce new aquatic life to spice up the pond, or to abandon some pets you might not wish to take care of any longer, doing so introduces invasive species and would disrupt the ecosystem in the pond, which can lead to disastrous results.
In Conclusion
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Though limited interest in marine biology may discourage many of us from hanging around the pond and making loving eye contact with the fish for hours on end, it wouldn’t hurt to start taking more of an active interest in the first functioning ecosystem you see every school day. After all, amidst the craziness of school life, temporary stress relief can always be achieved by going to the pond, to be blissfully alone with only your thoughts, the fish and the occasional fowl to keep you company.