By: Dr. Jillian Ooi
As usual today, on what has been designated World Ocean Day, we celebrate the watery realm of our planet and share heartfelt accounts of how the ocean has influenced our lives. Undoubtedly, ours is a maritime nation, surrounded as we are by the South China Sea, the Strait of Malacca, the Strait of Johor, and the Sulu-Sulawesi Sea. In almost every facet of our lives—from Malaysian cuisine, poetry, folk songs, and dance, to how we earn a living and build our homes—the ocean would have had a role to play in shaping it, whether we realize it or not.
But there is one part of the ocean that bears special attention and is the subject of this piece – our unique seagrass meadows. Seagrass has the unfortunate reputation of being the “ugly duckling” of the sea or worse, the “poorer cousin” of coral reefs and mangrove forests, but these humble plants are so much more. Seagrasses are flowering plants that look very much like the grass on our lawns except that they adapted 100 million years ago to life underwater, where they form lusciously green and verdant meadows in the shallow waters of our coasts. At low tide, some of these meadows are exposed to air for a few hours, and one can simply walk out to them – these are called intertidal meadows, which are buzzing hives of activity during those few hours of exposure. One may spot local villagers checking their fish cages for their daily catch, children poking amongst the seagrass leaves for shellfish such as clams and gong gong, and the odd naturalist angling for a money-making shot of grazing water birds.
But there are other meadows in deeper waters that are never exposed to air and they hold a special kind of beauty. These are known as subtidal meadows and are favored feeding grounds for green turtles and dugongs – those charismatic megafauna with enough star power to draw in crowds of local and international tourists seeking to experience the wonder of seeing these marine animals up-close. They are a major part of why tourists arrive in droves to islands such as Redang, Perhentian, Lang Tengah, Tioman, Sibu, and of course, the famed Turtle Islands Park of Sabah.
Tourist dollars are one thing, now let’s talk about what Malaysians hold dearest to our hearts – food! Seagrass meadows are breeding, nursery, and feeding grounds for marine life we are fond of eating. In the Mersing islands of Johor and the Setiu lagoon of Terengganu, for example, local scientists have shown that the subtidal meadows there are “fish kindergartens”, wherein juvenile fish feed and shelter before moving to coral reefs and mangroves in adulthood. But more than that, the type of fish that rely on seagrass meadows at some point in their life cycle are those very types that are popular seafood for us – emperor fish (ikan pelanduk), half-beak (ikan jolong-jolong), ponyfish (ikan kekek), mojarra (ikan kapas), rabbitfish (ikan dengkis), filefish (ikan gosok) and many more, including crabs, lobsters, and mollusks. Given that Malaysia is the third largest consumer of fish in Asia, after Japan and Korea, the role of seagrass meadows in providing seafood to Malaysians is a huge deal.
In coastal areas that are highly populated and lack proper sewerage systems, seagrass meadows reduce incidences of gastroenteritis illnesses caused by sewage pollution. They do this by filtering out bacterial pathogens such as Enterococcus, Escherichia, and Vibrio from seawater which, if ingested, could cause some measure of discomfort, or even fatality. A recent study led by the University of Palermo on Enterococcus alone, estimated that seagrass meadows around the world could be responsible for a reduction of at least 24 million cases of gastroenteritis each year, creating savings on healthcare amounting to at least US $74 million, globally. Such sanitation services also benefit other marine species by reducing the prevalence of disease in reef-building corals, fish, and invertebrates by half. Given that our coastal waters are so easily polluted by increasing loads of coastal populations, it is good news indeed that nature has blessed us with a natural means of sanitizing our seawater – all we need to do is to leave our seagrass meadows intact, and to let them work their magic.
One reason for seagrass being overlooked is because it looks so very humble. “It’s just grass”, is a common response to seeing these little sprigs of green on our shores. But let not their diminutive size fool us. These plants are effective in combating coastal erosion, and even the smallest and thinnest of the seagrass species, standing at less than five cm high, is able to keep the seafloor from getting eroded. For this reason, they are considered to be remarkable “ecological engineers” because they build and maintain stable seafloor that then becomes rich fisheries grounds. The reason for this is that seagrass meadows have a dense network of intertwined roots that are good at holding marine sediment together so that waves and wind cannot sweep them away. Moreover, within that sediment are huge amounts of carbon that come from decaying plants and animals that, if released, would contribute to warming up our atmosphere. Every atom of carbon kept protected and undisturbed within seagrass meadows simply means there is one less carbon atom available to heat up our atmosphere and to wreak havoc on our climate system.
Taken together, the services provided by seagrass have immeasurable value to us. Today, on World Ocean Day, when we celebrate the value of the ocean in our lives, let us start by getting to know seagrass better and in doing so, come to fully appreciate how this previously unseen and unregarded ecosystem has been silently providing Malaysians with food, clean water, protected shorelines, and income opportunities. Let this be the moment for the “ugly duckling” of the ocean to emerge graceful and cherished as a swan. Let this be when it claims its rightful position in the Malaysian psyche as an incomparable marine ecosystem with which we are blessed and could do better to protect.
Jillian Ooi is a Senior Lecturer at the Department of Geography, Faculty of Arts and Social Sciences, Universiti Malaya, and a lead researcher at the Team Sea Habitats lab. She enjoys watching seagrass grow in the hope to understand what makes it tick, its value to humanity, and how to conserve it. She may be contacted at jillian_03@um.edu.my for further details.