Scientists have found that coral cover in the South China Sea islands and reefs has declined drastically in the past decades, in some areas as much as by 80 percent. The Chinese government is strengthening governance and research to secure a sustainable future. Our reporter Han Bin re-visits a coral breeding center in southern China’s Hainan Province. He looks at how scientists there are addressing the challenges and the progress in helping restore the reefs.
An underwater tropical forest. The coral reefs of the South China Sea are part of a unique biome. And they are at risk of disappearing. This alarming situation has raised attention worldwide. For the past decade, Chinese scientists have been monitoring the coral habitat. This is one of the nurseries they're pinning their hopes on.
"There are numerous factors killing the corals, like the climate, alga, starfish, and overfishing, as well as island development. The survival rate can be as low as only one percent during the early period of baby corals. Our job is to increase their chances to survive and sustain," Zhang Yuyang, research fellow with South China Sea Institute of Oceanology, said.
Zhang Yuyang shows us their latest project. They collect naturally fertilized ova, and attach them to construction material. It takes one year to grow just one centimeter. Rehabilitation is the only method for restoration, one that takes time and money. The biggest challenge is to understand the whole eco-system.
From what we have learned, there’s been a rapid loss of coral reef habitat in the South China Sea. In some areas, coral cover has just about vanished. And the trend continues. That’s why restoration is crucial.
"The transplanting of corals will help speed up the restoration of surrounding corals. This will certainly take some ten to twenty years. But it might take fifty years or even one hundred years to recover on their own," Zhang said.
We got a chance to follow Zhang Yuyang’s team, on a transplanting operation. Everything must be done by hand, underwater. They say the loss of new corals will not only put the existing reefs under threat, but also threaten the existence of the reefs themselves in the long-term.
This is the same method they used in the Xishas. Zhang Yuyang says the best restoration is preservation. He dreams coral will once again thrive in the South China Sea.
"I really want to see one area of corals recover from dying through my work, to grow. I wish the corals we transplanted in the South China Sea to be surrounded with fish and other living creatures. That kind of happiness is beyond any words."
He will continue his underwater rescue mission. No matter how tough the way ahead or how rough the waters.