Seas off Trincomalee are set to welcome the birth of a new coral reef, courtesy Sri Lanka Navy. The recent decision to use two of its decommissioned ships to help support the formation of an artificial coral reef comes in the wake of the two underwater museums created by the Navy in this year, which would in fact turn out to be mini colonies of coral as well, in time to come. This highly laudable attempt should encourage the other agencies and stakeholders in Sri Lanka with regard to the need and the possibility of artificial reefs in support of our struggling coral reefs.
Incidentally, the sunken ships have formed quite a number of coral formations in various places in our home seas. Records speak of at least 200 such shipwrecks with almost all of them turned in to coral reefs as of today. Most famous among them is the World War 2 era aircraft carrier HMS Hermes, the huge ship of 600 feet in length lying just off the coast of Batticaloa, forming one of the largest artificial coral reefs in the world. Largest of them belongs to 900 feet long USS Oriskany, another aircraft carrier, sunken for the very purpose of creating a reef, off Florida in 2006.
Practice of artificial reef building goes back a few decades and such coral reefs are becoming common place in most of the tropical nations .USA has built quite a number of them off North Carolina using sunken ships .Australia too has placed concrete structures along estuaries producing an abundance of fish in them. Starting from 1978, with literally everything they could lay hands on- old train cabins, cars, tires, construction debris and even old battle tanks ,Thailand has built over 600 human made reefs covering an area of 2000 square kilometers, while neighboring India has converted once desolate region off Pondicherry in to creating the famous Temple Reef.
Similar efforts in Sri Lanka have been somewhat patchy, regrettably so. Apart from few private funded efforts such as one carried out by Holcim with the backing of International Union for Conservation of Nature, off Unawatuna, where they placed a number of purpose - built concrete structures in 2008, there have been little interest. Sri Lanka’s renowned explorer late Rodney Jonklass once unsuccessfully proposed the sinking of thousands of vehicles destroyed during the infamous July violence in1983, to facilitate coral formation. It is said that many of the bullet proof limousines used by Sri Lanka’s leaders, including those used by LTTE ended their lives in deep seas off Colombo preferably supporting marine life now.
Encouraging signs elsewhere
It has been a proven fact that marine life appears to have found a liking to these artificial reefs of steel and concrete. Although the exact reasons are not known, the scientists opine that one reason could be the numerous nooks and crannies in these structures that may provide better protection to small fish from the predators. These structures have created thriving colonies everywhere they were placed and that there has been no noticeable negative impact on the existing natural coral formations situated nearby, as extensive studies conducted both by US National Oceanic and Atmospheric Administration, University of New South Wales ,Australia and other bodies have shown .
This would be a highly encouraging sign since much of the world’s coral reefs have faced heavy damage due to both man and vagaries of Nature . Multiple factors have led to depletion of coral, from increased pollution, illegal fishing, trawling, due to ornamental fishing industry and over tourism etc. Virtually all of these factors contribute to the ruination of Sri Lanka’s remaining reefs where abuse and pollution appear to have done substantial damage to even the Marine Sanctuary in Hikkaduwa. The other Marine Sanctuaries in the island are the Bar Reef, located off Kalpitiya, which too suffers from a number of issues such as silting, and the other being Pigeon Island Sanctuary that still remains largely intact from human interference. Damage to various other coral formations scattered around Sri Lanka’s territorial sea has been worse.
In addition, the coral reefs in the world are taking the brunt of the impact of climate change, from rising temperatures, ocean acidification as well as bleaching. It was just a few week back the researchers have found that the Famed Great Barrier Reef is losing its ability to recover itself after sustained bleaching of coral. It brings to mind the large scale bleaching of coral in Sri Lanka that severely damaged our reefs in 1998, and again in 2016, much of which still to be recovered fully.
Laws’ failure and the need for intervention
Sri Lanka, with over 1385 kilometers of coast, with three times as much territory in sea than its land, depend on the coral reefs for much of its fishing .Virtually all of our reefs are located within 40km from the shore and much of the nation’s fishing stock is harvested from within this area in the ocean. In spite of substantial laws such as Fauna and Flora Act, Fisheries and Aquatic Resources Act, Marine Pollution Act etc, covering our ocean wealth, there has been a heavy depletion during the previous decades. Although laws have been helpful in curbing practices such as coral mining for lime, many other harmful activities continue, causing continuous damage to the unique marine ecosystem supporting hundreds of species of aquatic life. In fact our laws on the ocean are an apt example of the extent of ineffectiveness of these rules, when the enforcement has fallen through, resulting in open violations.
What’s at stake is the very survival of a species that’s invaluable both ecologically and economically. Highly promising results shown in the artificial mini reef at Unawatuna could be a beacon for similar projects. It’s said the Navy was initially interested in using decrepit railway cabins for the underwater museum in Galle-an idea worth perusing since availability of abandoned railway cabins and chassis of buses are plentiful in various yards. Many countries have successfully utilized selected concrete debris taken from construction projects as well.
Existing threat levels to coral formations in our seas would make it imperative for developing human made reefs while taking measures to ensure restoration and protection of natural habitat .Coral act as a formidable defense against threats from the ocean waves. It would be pertinent to note that Maldives suffered only little damage from the Tsunami 2004, thanks to its coral reef that stood in the way of the onrushing wave .Similarly, the offshore reefs contributed to taming the Tsunami in multiple places in Sri Lanka, such as Panama.
As research shows, the Ocean off Sri Lanka has an average depth of just less than 70 meters with a degree of regularity of sandy and rocky floors, which could support the forming of new colonies of coral with assistance in the form of artificial structures. South and South West of the island with limited colonies of coral could be backed up by repeating the phenomenal success in multiple shipwrecks with vibrant marine life that dot the seas off shore. East and the North Western sea boards with lower levels of disruptive sedimentation, and even the islands off Jaffna with lesser presence of coral could benefit from human made reefs
The act by the SL Navy in the scuttling of SLNS Weeraya [P311] and SLNSJagatha [P315]-the old warriors each with over four decades service, in bringing the topic to the fore should encourage and inspire other stakeholders, along with the social responsibility by the corporate sector, to make a worthwhile effort at rejuvenation of the reefs of Sri Lanka. (KS).