Reef structure to promote coral growth installed off Sisters' Islands

Each of the 10m-high structure will form a three-storey "terrace house" upon which corals may take root and grow. ST PHOTO: ONG WEE JIN

SINGAPORE - The Republic's largest man-made reef structure to date was installed on Thursday (Nov 8) in the waters off the 3ha Small Sister's Island, which is south of Sentosa and about a 45-minute boat ride from Marina South Pier.

It is part of an installation that comprises eight reef structures in total, all fabricated off-site. They will be fully installed by the end of 2018.

When the corals grow, these reef structures are expected to contribute some 1,000 sq m of additional reef substrate to the Sisters' Islands Marine Park by 2030.

The installation constitutes an important expansion of conservation efforts in Singapore's Southern Islands, of which the Sisters' Islands are a part of, and is part of the "Grow-a-Reef Garden" project, a collaboration between JTC and the National Parks Board (NParks).

First announced in May this year, the project was proposed as part of efforts to protect the coral reefs around Singapore and enhance marine biodiversity in the island's surrounding waters.

Each of the 10m-high structure will form a three-storey "terrace house" upon which corals may take root and grow, while also doubling up as a new home for other forms of marine life to live in and flourish, said Speaker of Parliament Tan Chuan-Jin, who witnessed the installation of the first structure on Thursday.

Representatives from JTC and NParks, members of the Friends of Marine Park Community, donor companies, industry guests, as well as local marine research and interest groups also attended the event.

The structures will sit in the 40ha Sisters' Islands Marine Park, about the size of 50 football fields, which comprises the Big Sister's Island and the Small Sister's Island and their surrounding reefs, as well as the western reefs of nearby St John's Island and Pulau Tekukor.

They are made of materials including concrete, fibreglass pipes, steel and rocks recycled from other JTC projects. Each structure includes nooks and crannies within which various fish species and other forms of sea life may find shelter and thrive.

To date, there has not been a reef installation on a larger scale in Singapore.

Eleven donor companies have pledged support to the initiative, each contributing sums ranging from $5,000 to $100,000, for a total of $290,000.

Besides helping to pay for the implementation of the reef structure project, the monies will fund monitoring programmes, research projects, education and public outreach activities.

"We are heartened by the generous support from our industry partners on the "Grow-a-Reef Garden" Initiative," said Mr Ng Lang, chief executive of JTC.

"We hope that more from the industry and community will join us to create a more sustainable environment."

Speaker of Parliament Tan Chuan-Jin (centre) witnessed the installation of the first structure on Nov 8. Mr Tan said long-term conservation and management of Singapore's coastal and marine environment are essential for Singapore's future. ST PHOTO: ONG WEE JIN

The reef structures are intended to transform bare seabed into a flourishing marine ecosystem, allowing corals to take root, and in turn attract fish and other marine life.

"The project... will be significant in supporting marine habitat enhancement and reef restoration efforts," said Mr Tan.

He added: "There is no silver bullet to overcome our environmental challenges. What we need is a range of multi-disciplinary solutions involving expertise from different parties."

Mr Tan said long-term conservation and management of Singapore's coastal and marine environment are essential for Singapore's future.

"This is particularly timely as the International Coral Reef Initiative has designated this year as the International Year of the Reef, and this project will help our efforts in enhancing Singapore's coral reef ecosystems," he added.

Restoring reef substrate is an essential step to recover damaged reefs that have become unsuitable for coral populations to settle.

The new reef structure installed on Thursday will provide new substrate for corals to attach to and grow, mimicking the natural coral reef habitats observed around Singapore.

After they are installed, they will be monitored through research initiatives coordinated by NParks which will involve various marine interest groups.

Mr Kenneth Er, chief executive of NParks, said the project will facilitate research initiatives that will go a long way in supporting conservation efforts in other marine areas of Singapore.

"Our marine biodiversity is our common natural heritage, and we are glad to see partners stepping forward to conserve it," Mr Er added.

Singapore has lost approximately 60 per cent of its reefs to land reclamation over the years.

Local reefs are also recovering from a bout of bleaching in 2016, which was caused by a prolonged period of high sea surface temperatures.

Corals that are stressed by sudden changes in temperature, light, or nutrient levels expel the microscopic algae that live in their tissues.

The algae, called zooxanthellae, have a symbiotic relationship with the corals. They are the coral's primary food source, and give a coral its colour.

Without the algae, the coral is deprived of its major source of nutrients. It then turns white or very pale, and becomes very susceptible to diseases.

Partially bleached corals were observed around Big Sister's Island in November 2016. It was estimated that about 15 to 20 per cent of corals in Singapore's waters died because of the bleaching.

In a statement, NParks said the installation complements other efforts to expand the scope and scale of other marine habitat restoration programmes. For instance, the NParks in-situ coral nursery will also be established in this Reef Garden.

Rare corals that may be threatened by coral bleaching can also be moved to this controlled environment, in an attempt to ensure their survival.

"We are heartened by the efforts of the business community in sharing our goals to conserve marine biodiversity and encourage vibrancy at the Sisters' Islands Marine Park," said Mr Stephen Beng, chairman of the Friends of Marine Park community.

"We are hopeful about the enhancement benefits this new reef habitat will bring to life in our waters."

Correction note: In an earlier version of the article, one mention of Sisters' Islands Marine Park was misspelt. We are sorry for the error.

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