Coral Restoration Research Papers - Academia.edu (original) (raw)

Coral reefs of Vizhinjam sea at the verge of destruction The recent discovery of coral bleaching in the Kerala coast compounds the concern about the destruction of marine ecosystem. The disturbing visuals of bleaching were captured from... more

Coral reefs of Vizhinjam sea at the verge of destruction

The recent discovery of coral bleaching in the Kerala coast compounds the concern about the destruction of marine ecosystem. The disturbing visuals of bleaching were captured from Vizhinjam sea by citizen scientist divers and comes in the wake of heightened global action for coral protection. Despite repeated warnings about the health of the corals in the state, it is worrying that there no scientific study is being conducted locally. Continuing apathy would lead to irreversible environmental impacts that will destroy several marine species, lead to aggressive beach erosion and raise the overall temperature of the sea.

Thiruvananthapuram/Kerala :As the Vizhinjam International Deepwater seaport project in Thiruvananthapuram is progressing, the coral reefs nearby are at the verge of destruction. Evidence, including photographs, reveal that they are in different stages of bleaching. This phenomenon will adversely affect a wide variety of ornamental fishes and lead to detrimental environmental issues like ocean warming and rampant beach erosion.

Coral bleaching at Vizhinjam was discovered during an investigation for Earth Journalism Fellowship. Bleaching was found in Goniastrea species that form the base of the coral reef colonies. Scuba divers who are also Citizen Scientists, have photographed the phemenonfrom the sea in between the Vizhinjamseaport project region and the Vizhinjamharbour.

Reasons galore

Bleaching can be caused by global warming, ocean warming, cold water, ocean acidification, and carbon emissionas well as increase in nutrients. Daniela Ceccarelli, Australian Marine ecology consultant clarified that coral reefs can be destroyed due to floods and cyclones. The Kerala floodsin 2018 and the cyclones like Gaja 2018, Fani 2019, Ockhi2017 too might have caused the bleaching, she opined.

This situation can also be a result of heavy sedimentation, explained Professor Morgan Pratchett from James Cook University ARC Centre of Excellence for Coral Reef Studies, Australia.''There is a definite possibility that localised bleaching is caused by deposition of sediment nearby, but it might also be related to extreme environmental conditions. There is no doubt that excess ¬¬sediment makes corals less resilient and more susceptible to extrinsic stressors. Most importantly, high levels of suspended sediment reduce the amount of sunlight required for corals to photosynthesize and derive energy,” he says.

Robert Panippilla and Aneesha Ani Benedict, scuba divers and administrators of the Ocean Literacy Programme Organization (Friends of Marine Life) based at Valiyathura in Thiruvananthapuram took videos from this approach channel.The two Australian scientists who had analyzed the video clarified that the actual impact can only be identified if studies are carried out before and after the port construction and natural calamities. They called for continuous evaluation. However, when enquired, it was revealed that necessary studies on the coral reefs of the region were not carried out before or after the dredging.

Even the Environmental Impact Assessment Report on Vizhinjam seaport only mentions the studies conducted years back by the scientists from the government agencies who envisaged to study about the sea, identify issues and suggest solutions. The Environmental Impact Report submitted together by L&T and Rambøll Consulting Engineers Limited for the Vizhinjam seaport contains the studies published in 2009 by Dr Jasmine, Principal Scientist, Central Marine Fisheries Research Institute (CMFRI), who continuously conducts research on hard corals. According to her research, Vizhinjam area has nine types of coral reefs and they are scattered in different areas. She added that there are some patchy reefs.
Coral reefs the abode of piscine community

In the Environmental Impact Assessment Report for the Vizhinjam seaport project, an annexure prepared by the Aquatic and Fisheries Department of Kerala University listed 69 ornamental fish species that reside in the coral reefs of Vizhinjam shore. When coral bleaching occurs the existence of creatures residing in its vicinity including ornamental fishes are threatened, says Pratchett.

“Ornamental fishes are negatively affected by increased suspended sediment. The key finding was that fishes exposed to elevated sediment levels had reduced capacity to obtain oxygen due to inflamed gill filaments. The link between the dredging and sediment deposition would certainly be more apparent if there was a rigorous Environmental Impact Assessment (EIA) being conducted and I would’ve thought it necessary to have done this given the vulnerability and loss of coral reef environments worldwide,” he says.

''However, it is also not too late for local scientists to start assessing the impact and collect all the necessary environmental conditions to rule out whether the bleaching was simply coincidental and caused by changing environmental conditions or directly attributable to elevated levels of suspended sediment or sediment settling on the corals themselves,” he says.

Disastrous developments

The health of the patchy reefs at Vizhinjam was already being threatened by the dredging activities done for the seaport project as well was the increased dumping of plastic waste into the sea. Fishermen say that when dredging was carried out in the sea for the Vizhinjam project, soil from the nearby Vizhinjam harbour was drained and deposited at the approach channel in between the two breakwaters. This has led to heavy losses regularly due to capsizing of boats. They testify that due to the dredging and increased draining of sand, silt is being deposited at the sea in Vizhinjam.
Dr A Biju Kumar, Dean and Head of Aquatic and Fisheries Department of Kerala University Thiruvananthapuram says that the coral bleaching found in Vizhinjam might be part of the coral bleaching happening across the co¬¬untry. ‘’During last summer, the rate of coral bleaching increased across the country due to ocean warming. Coral bleaching was discovered in Vizhinjam for the first time. The rate of sedimentation is increasing due to the port project. Studies have been conducted years ago that patchy coral is present in the Vizhinjam offshore. After that there were no further studies,’’he says.

Dumping of plastic waste in sea, directly and indirectly, has been impacting marine life and coral health for years now. There are lot of ghost nets too. Plastic waste is getting piled up in Vizhinjam due to steep rockyreefs and deep terrain. During the sea turbulence in June 2019, due to heavy rains, five tonnes of plastic waste was deposited back from the sea at the Kovalam beach in two days. As per the audit conducted by the FML workers, it was understood that 90 percentage of this consisted of plastic, nylon, PVC, rubber, polyester, leather and thermocol. The rest comprised of iron, tin, wood and the like.

Act now to save the reefs

While majority of the scientific community has rung alarm bells, a few are of the opinion that bleaching is reversible. Dr. Benno Perera, a marine scientist and academician at Kochi claims that the corals are recovery.

''These types of Goniastrea corals are also found on the Great Barrier Reef, and they do quite well in poor water quality conditions (high-nutrient, high-sediment). They're tough, as far as corals go, and when they bleach, they can often recover once conditions return to normal,'' says Daniela Ceccarelli.

This ‘return to normalcy’ is the key word phrase here. The coral reefs, for its growth, need permanently saline pristine waterwith the availability of ample sunlight and 20-30 degree of temperature, Perera says. “Generally during monsoon season, lot of river water flows in, which lowers the salinity of the sea water and increases the coldness. This is the reason behind scanty coral reef growth in the coastal regions of Kerala in comparison with other countries,” he explains.

We must act fast to reinstate normalcy. First and foremost, dumping plastic waste must be curtailed on a war footing. Breaking corals from reefs is illegal now and the public must refrain from buying them as curios from vendors at beaches. The report filed by the environmental commission set up by the state government after the 2018 floods have pointed out the need for more research on coral reefs. They have also proposed an environment policy that will educate children about the need to conserve nature and marine ecosystems like coral reefs to prevent devastating climate changes.

photos: 1 bleaching Goniastrea coral, captured ¬¬ from vizhinjam harbour mouth, Thiruvanathapuram, India -Photo by FML

Ms. Aneesha Ani Benedict and Mr. Robert Panippillai