Diver pieces back together smashed marine ecosystem

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Bleaching is a major concern for coral reefs and the marine ecosystem they represent. (Photo/China Daily)

Having immersed himself in marine conservation for over a decade, Wang Fengguo possesses a profound understanding of the havoc that extreme typhoons can wreak upon coral reefs, which stand as some of the planet's most diverse ecosystems, amid the escalating climate crisis.

The destructive force and powerful currents generated by such typhoons smash into the reefs, causing them to break into thousands of fragments. In the aftermath, the corals resemble puzzle pieces scattered all over the seafloor.

"When extreme typhoons occur, they trigger underwater floods," the 42-year-old said, reflecting on the devastating typhoons that struck Wuzhizhou Island in Sanya, Hainan province, around 2008. "They bored deep gullies into the coral beds."

A fervent diving enthusiast, Wang has found solace and delight beneath the ocean surface. This ardor and his sorrow for the deteriorating coral ecosystems have seamlessly evolved into his present post as head of ocean management at Wuzhizhou Island Tourism Resort, where he merges his diving skills with his unwavering commitment to coral conservation.

Through his extensive involvement in coral restoration, Wang has seen firsthand the transformative power of the collaborative endeavors of businesses, institutions, and the government, yielding a mutually beneficial outcome: the revival of vibrant underwater landscapes alongside the promotion of economic growth.

A coral nursery in the ocean ranch near Wuzhizhou Island, Hainan province, in March 2016. (Photo/Xinhua)

A coral restoration program launched on the island in 2016 has transformed Wuzhizhou, a popular diving destination, into a model of sustainable marine tourism, where ecological improvement and tourism coexist harmoniously.

In 2009, in a move to protect the marine environment around the almost 1.5-square-kilometer island, which attracts millions of tourists every year with its stunning tropical coastal scenery, the resort established an office of ocean management.

Wang, who started work at the resort as a diving instructor in 2006, joined the office in 2011, after the island launched a marine ranching project.

"The marine ranch in Wuzhizhou differs a lot from many others," Wang said, adding that while many other ranches are for fish farming, the one in Wuzhizhou aims to conserve the marine resources the island depends on to attract tourists, especially those beneath the water, such as fish and coral reefs.

"Once the local ecosystem improves, that will be of great help to the tourism industry," he noted.

At the very beginning, a focus in the construction of the fish ranch was to establish artificial fish reefs and stock hatchery-grown fish in the wild. In 2014, the idea of restoring the damaged coral reefs by planting them came to Wang when the experimental trial of a researcher from the Hainan Academy of Ocean and Fisheries Sciences on the island achieved initial success.

Wang Fengguo (right) and a fellow diver transplant corals at the ranch in May last year. (Yang Guanyu/Xinhua)

In that year, he discovered that many broken corals transplanted by the researcher onto a steel frame underwater a year earlier, which works as a nursery, had not only survived but thrived, eventually spreading out.

With the help of the local government, Wang got in touch with the South China Sea Institute of Oceanology at the Chinese Academy of Sciences, which has a team long dedicated to coral research. In 2016, after more experimental planting, the Wuzhihzou resort decided to carry out large-scale planting.

Since then, in addition to maintaining their ongoing efforts in collecting marine debris and monitoring and patrolling the marine ranch, Wang's team has dedicated as many as three months each year to cultivating coral seedlings and conducting coral planting.

"It has become a regular work activity for the resort," he said, adding, in total, the resort has invested over 10 million yuan ($1.37 million) into coral restoration.

According to the resort, as of April, with the backing of the local authorities in Hainan and Sanya, as well as support from Hainan University and the Ministry of Agriculture and Rural Affairs, the investment in the construction of the marine ranch, which covers the coral restoration program, has totaled 90 million yuan.

A total of 80,000 cubic meters of artificial fish reefs have been built, and over 51,000 coral seedlings have been transplanted, covering an area of 53,000 square meters.

Wang said 3,000 to 4,000 sq m of the seedlings were planted just a few months ago, and they still need to withstand the test of time.

"After transplanting coral seedlings from the nursery, they must grow naturally. We will regularly inspect for any casualties, conduct replenishment, and address potential threats as needed," he said. "Apart from these efforts, our ability to assist further is limited."

A clown fish swims among sea anemones near Wuzhizhou in May. (Photo/Xinhua)

The consistent efforts from the resort have not only resulted in an improved marine ecosystem in the area, but also have seen tourism boom on the island, according to Wang.

As a regular diver, he has witnessed a remarkable growth in the number of fish in the area, both small ones and big predators, he said. In recent years, he has frequently run into giant groupers, a creature he seldom saw before, and he believes one of them, which inhabits a boat sank on purpose to act as a reef, weighs more than 100 kilograms.

What is beyond Wang's imagination is that a seal, which is endemic to sea areas with cold water, has also been observed roaming in the area, he said.

Wang added the island's annual diving revenue now totals hundreds of millions of yuan.

Attracted by the vibrant coral reefs, You Ling, owner of the 57 Diving School in Sanya, has explored many popular diving destinations worldwide, including French Polynesia and Fiji. She considers the diving site in Wuzhizhou to be the standout choice in Sanya compared to other diving spots.

The 52-year-old emphasized the contribution of the coral restoration efforts to its distinction compared with other areas in Sanya.

"In Sanya, many underwater areas are desolate, plagued by extensive sand deposits with silt and debris, lacking the allure of overseas diving paradises," she said. "Nevertheless, Wuzhizhou defies this trend. Its vibrant corals, displaying an array of colors and formations, congregate like a naturally cultivated garden."

The diving school owner echoed Wang, saying that she has found an increase in both fish number and variety in Wuzhizhou.

Wang Aimin, a retired professor of marine biology at Hainan University, said the increase of fish in the Wuzhizhou area, a result of the marine ranch construction, has indeed facilitated coral restoration.

Fish, particularly algae-eating species, can help control diatoms, which often cover coral and compete with zooxanthellae, a crucial symbiotic algae that lives within the tissues of coral polyps, for light, he explained.

With a mutually beneficial relationship with the coral, zooxanthellae can convert sunlight into energy through photosynthesis. Through this process, they provide the coral with essential nutrients such as glucose, glycerol, and amino acids.

Wang depicted a vibrant scene in some areas around Wuzhizhou, saying "The corals there thrive abundantly, forming thick layers one upon another".

This has happened because of the abundant fish population in the region, he said, adding the Wuzhizhou resort's stringent control on fishing has significantly deterred fishermen.

Had overfishing not been brought under control, "the absence of any marine species in the ocean ecosystem can lead to problems", he stressed, adding that the depletion of fishery resources would jeopardize the living environment for corals.

Corals are cultivated in a lab in Hainan. (Photo/China Daily)

The construction of the marine ranch in Wuzhizhou has effectively supplemented fish as an essential element required to uphold the delicate balance of the region's ecosystems, consequently improving the health of coral reefs, he said.

Despite the positive progress in Wuzhizhou, Zhang Yuyang, an associate professor with the South China Sea Institute of Oceanology, said there remains a generally grim situation for coral reefs because of global warming, which has resulted in coral bleaching.

In total, the institute has planted over 300,000 coral fragments in the waters around Xisha and Nansha islands and near Hainan Island, the expert said.

Though over 5 hectares of coral reef have been restored in Wuzhizhou, that represents no more than 1 percent of the total area that needs to be restored. "Generally, the restored area is significantly smaller in scale than the area that still requires restoration," Zhang said.

"The situation is grim with no good solution at the moment," he added.

According to a release from the United States National Oceanic and Atmospheric Administration and International Coral Reef Initiative in April, the world was experiencing its fourth global coral bleaching event, the second in the last 10 years.

"From February 2023 to April 2024, significant coral bleaching has been documented in both the northern and southern hemispheres of each major ocean basin," Derek Manzello, coordinator with NOAA's Coral Reef Watch, was quoted as saying in the release.

The mass bleaching of coral reefs since early 2023 has been confirmed in at least 53 countries, territories, and local economies, the release added.

Zhang emphasized that the advancements in coral restoration in Wuzhizhou underscore the potential for safeguarding a genetic resource site amid challenges caused by climate change.

"The crucial importance of coral restoration is in maintaining a robust genetic habitat for deteriorating coral reefs. If all coral reefs degrade with no healthy ones left, then there will be not even a glimmer of hope for any potential recovery," he said.

But the glimmer of hope in Wuzhizhou could potentially grow even brighter, thanks to consistent efforts by the resort and Wang Fengguo.

According to Wang Fengguo, the resort plans to invest 20 million yuan a year in the coming five years to promote the construction of the marine ranch's second phase.

Working in the ocean poses inherent risks. He and his colleagues often suffer cuts and bruises during coral transplanting operations that often last for 3 to 4 hours. Due to prolonged periods underwater, he also experiences severe eczema.

Despite the challenges, Wang Fengguo remains dedicated to his mission as he approaches his 20th year in Wuzhizhou.

"This work is meaningful," he said. "Our work is for future generations. We might not see all the benefits now, but we are laying the foundation for a healthier ocean."