In Hainan's coastal waters, speedboats dart between floating guesthouses while inside towering aquaculture facilities, technicians monitor tanks of breeding shrimp. These contrasting scenes illustrate the transformation of China's southern island province, where ocean-related industries grew to 300 billion yuan ($41.9 billion) last year, marking a 13.9 percent annual increase since 2020.

The tropical province is rapidly shifting from traditional fishing to modern marine industries, with high-tech fish farming and coastal tourism driving the boom.

At the forefront is the Fengjiawan Modern Fishery Industrial Park in Wenchang, where 55 aquaculture firms and research institutes have set up operations in demonstration buildings.

In the late 1980s, Fengjiawan Bay was known as a major base for shrimp seedlings. However, extensive fish farming and uncontrolled wastewater discharge led to beach pollution. In 2020, the local government began building the modern fishery park, exploring multilayered breeding models and promoting a green transformation of the fishery industry.

Xinbang Marine Biotechnology, the park's first tenant, settled in the bay in 2021. It has seen annual production value grow from 63.3 million yuan in 2023 to 70.8 million yuan last year.

"The location gives us fast airport access for shipping breeding shrimp across Asia within hours," said project manager He Qiang, noting the 50-minute drive to Haikou Meilan International Airport's cargo terminals.

The industrial park exemplifies Hainan's shift from wild catches to controlled breeding.

"Hainan's tropical climate and high-quality seawater provide ideal conditions for breeding our South American white shrimp fry, enabling faster growth, stronger disease resistance and shorter production cycles," He said.

In addition, the park's centralized water supply, wastewater treatment and well-planned infrastructure allow businesses to focus on production.

Xinbang plans to launch new shrimp varieties for southern Chinese markets and has invested heavily in breeding technology, leveraging Hainan's tropical waters to naturally enhance disease resistance.

"Our next phase focuses on sustainable operations," He said, adding that the company has already generated 40 million yuan in the first half of this year.

About 110 miles south in Lingshui Li autonomous county, former fishermen have converted 400 floating homes into a "sea village" tourism destination.

Guo Yudong's family transformed their 1990s fishing raft into the Blue Bay Clear Waves Restaurant, now serving up to 300 diners daily with dishes such as puffer fish porridge and coconut-flavored squid.

"Tourists fly here just to eat where their food was caught," said Guo, whose grandfather started the business with four tables.

In Hainan, the largest community of the Danjia people — fishermen who also live at sea in Fujian, Guangdong and Guangxi provinces — is based in Lingshui.

In 2021, the Danjia Floating Homestay Association began converting aging aquaculture rafts into floating homestays, offering visitors a taste of the traditional Danjia "boat-dweller" culture. The project, led by nine Communist Party members and 85 fishermen, now features glass-bottom boat rides, night fishing and beach-combing activities at low tide. A museum displays Danjia artifacts such as wooden planes, wedding fans and fishing tools to share the community's seafaring heritage.

"It's completely different from land-based stays," said visitor Sun Ye from Beijing, who returns annually for the "authentic waterborne lifestyle". "Local families teach us to fish and speak their dialect. We will keep coming back."

Marine leisure industries are seeing similar growth. Last year, Hainan hosted 1.26 million yacht tourists across 700 marine tourism companies, with 11 marinas now operational, according to the provincial department of tourism, culture, radio, television and sports. The Xisha Islands cruise route has become a staple, while international sailing competitions have anchored an expanding events calendar.