The South China Sea is located in the Indo-Pacific region which includes the tropical waters of the Indian Ocean and the Pacific Ocean. The South China Sea covers approximately 3.5 million square kilometers (Thi Lan Anh et al., 2025). It encompasses China, Vietnam, Indonesia, Malaysia, the Philippines, Brunei, and Taiwan (Trajano et al., 2017). The SCS is an important maritime area since it is estimated that around 30% of global trade across seas is connected by the waters (Thi Lan Anh et al., 2025).

The Con Dao Islands is one of the top tourist destinations in Vietnam (Vn Express, 2024). Surveys in the Con Dao Islands of Vietnam show the mass mortality (20%–90%) of coral reefs since 2005 (Vo et al., 2019). The combination of high water temperatures in a short period and the sudden decrease of salinity in the water contributed to the bleaching (Vo et al., 2019). These coral death events have occurred frequently at the islands, with the most severe instances being in 1998, 2010 and 2016 due to El Nino (Vn Express, 2024).

The marine protected area of the Nha Trang Bay is mainly focused on biodiversity conservation of coral reefs in the core zones of the Hon Mun and Hon Cau Islands (Vo et al., 2019). The coral reefs from these islands have favorable physical conditions in the reduction of heat stress which is important to viable reef rehabilitation (Vo et al., 2019). They currently have a healthy status, however, if degraded reef resilience would decrease.

The South China Sea is and will continue to become more acidic, as with other global marine ecosystems. The degree of acidification will be somewhat uniform throughout the South China Sea area (Trajano et al., 2017). The surface of the SCS will become 0.3 to 0.35 pH levels more acidic (Trajano et al., 2017). Unfortunately, there is not enough knowledge on the ability of coral reefs to adapt to this level of ocean acidification (Trajano et al., 2017).

Sea level rise driven by climate change impacts will worsen the conditions of coral reef habitats in these marine ecosystems.

The estimated changes of sea level rise ranges from 2 to 4 mm per year at the waters east of the Malaysia and from 4 to 6 mm per year off the waters of the

northwestern coast of Borneo island (Trajano et al., 2017).

The South China Sea (SCS) is a diverse marine ecosystem, hosting 76 percent of the world’s coral species, which is very high (Trajano et al., 2017). However, environmental degradation has continued to increase by both natural and human damage. According to the Southeast Asian Fisheries Development Centre in Bangkok, Thailand, 16 percent of live coral cover has been lost every ten years since 2007 (Trajano et al., 2017). Coral cover is the total cover of hard and soft corals (Vo et al., 2019). This means that by 2027 which is in the next two years, 48 percent of live coral cover in the SCS will be considered dead.

Unlike most coral reefs, the Spratly Islands is one of the few cases where the environment is mainly covered by dense coral coverage (McManus, 2017). The dense coral coverage characterized in the Spratly Islands is made up of small branching corals and boulder-like “massive corals” (McManus, 2017). Much of the damage shown is caused by China’s artificial island building (McManus, 2017).

These ongoing protests involve the disputed waters and coral reefs of the Scarborough Shoal (The Japan Times, 2016). The Scarborough Shoal has faced poaching and overfishing mainly by Chinese fishermen (McManus, 2017). A policy approach to assist coral reef protection suggested by McManus is the establishment of a Peace Park. A Scarborough Shoal Peace Park could ease conflict between the Philippines and the PRC. Benefits of a peace park for both countries include tourist income and protection of traditional fishing grounds for locals (McManus, 2017). Easing conflict would better support necessary bilateral collaboration and coral reef protection (McManus, 2017).

The Thitu Reefs is a larger area of reefs in the SCS, with rich fishing grounds (NPR, 2024). In 2015, the People’s Republic of China (PRC) was found harvesting giant clams in the reefs (McManus, 2017). PRC boats from these events were chopping down giant clams and corals in at least two dozen reefs of the region (McManus, 2017). This caused major ecological damage and contributed to continued conflict with the Philippines which is one of the claimants of these islands (NPR, 2024).

For coastal communities in the South China Sea, the loss of healthy coral reefs has impacted the avaliability of fish protein. Fishing is essential to the nutrition and livelihoods of locals. The SCS is a vital ecosystem for fisheries because it holds 22% of the world’s fish species (CSIS, 2023).

Artificial island building and dredging of complete coral reef structures has heightened international tensions around environmental resolutions. Dredging is the removal of silt, sediments, and other materials such as corals from the seabed (CSIS, 2023). Cutting, which is performed along with dredging, is the physical process of destroying coral reefs and other marine plants, creating long term damage.