Singapore has spent $6 million on relocating more than 2,000 coral colonies which were in the way of a port development in Tuas.
They were moved from Sultan Shoal, south of Tuas, to the waters off St John's and Sisters' islands as land reclamation necessary for the port development could destroy them.
The Maritime and Port Authority of Singapore (MPA) said the expenditure, listed in the 2016 Budget Book, includes work started in 2013 and which will continue up to 2019.
A spokesman said it covers "coral relocation works, development of coral nurseries, including transplanting of the grown coral fragments to new locations, monitoring of coral health in the new recipient sites, and monitoring of the remaining corals at Sultan Shoal".
He said the project arose from an environmental impact study carried out in 2012.
Such studies are mandated by the Government, the MPA said, and the previous one was done before the Pasir Panjang terminals were built.
The Sultan Shoal coral relocation project was done with the National University of Singapore (NUS) and and the National Parks Board (NParks).
Some 2,300 out of 2,800 coral colonies were moved successfully and have survived.
"MPA continues to monitor the health and growth of the relocated corals," its spokesman added.
Between now and 2019, the authority will monitor the health of remaining corals at Sultan Shoal.
Some coral fragments were also transplanted to Kusu Island, Lazarus East and Lazarus West "to rehabilitate the degraded reefs, and to establish new reef communities at non-reef areas", he said.
SIM University senior lecturer Jason Morris-Jung said: "There is no benchmark to determine the dollars and cents' worth of any particular conservation project that I am aware of.
"They usually need to be calculated on a case-by-case basis, depending on the particular characteristics of an eco-system and its particular human benefits or uses."
He noted that coral reefs are important spawning and feeding grounds for fish, and hence they contribute to ocean fisheries.
"People also pay money to visit, snorkel and dive around coral reefs," he said, adding that reefs also protect against coastal erosion.
He cited a World Wide Fund for Nature study, which estimated the global economic value of coral reefs at US$30 billion (S$40.5 billion).
The World Resources Institute said the cost of destroying 1km of coral reef ranges between US$137,000 and $1.2 million over a 25-year period.
"Some years ago, Dubai paid US$10 million to relocate some 20,000 coral colonies," Dr Morris- Jung noted.
But he added that any financial analysis is inadequate because it is hard to put a value to an ecology that has taken "thousands or even millions of years to develop".
This article was first published on April 23, 2016.
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