Buoyed by its long coastline, beautiful bays, harbours and more than 3,000 islands, Vietnam understands – as do other coastal nations – the threats from climate change , illegal and unregulated fishing , rising sea levels and habitat destruction. While the tensions over sovereignty claims in the South China Sea still exist, Southeast Asian nations and China are embracing marine protected areas (MPAs) to support the health of the ocean. The science is clear: create a place of refuge in which marine life can thrive and the results provide more fish for all. It’s a practice that is proving successful. In the face of dire environmental challenges, more governments are committed to protecting up to 30 per cent of the ocean territory by 2030. This is especially important in Southeast Asia, which is home to some of our planet’s most biologically diverse coral reefs . A recent study in the journal Science on marine conservation confirms that although ocean ecosystems are complex and dynamic, the spillover benefits at Hawaii’s largest fully protected MPA supports the increased number of two migratory species, bigeye and yellowfin tuna. This is significant since previous research cast doubt on the potential for MPAs to provide refuge for migratory fish. With the collapse of fisheries in the South China Sea, marine protected areas offer a safety net that is a non-threatening measure for claimant nations to get behind. China knows it is in dangerous waters since it has entered the “ecological conservation redline”, which reflects Beijing’s urgency to protect marine spaces from development. In the past two decades, it has lost vast swathes of its mangrove cover and more than 80 per cent of its coral reefs. In an era of rapid environmental shifts and unprecedented economic development, China has joined ranks with Southeast Asian countries in undertaking the roll-out of MPAs. Within these no-development zones, conserving and restoring degraded coastal ecosystems are priorities. This stepped-up protection of its designated marine areas is visible in its more than 270 MPAs. A 2021 research article in Science Advances states that China’s MPAs “protect rare or endangered species and ecosystems. They are no-take, meaning any extraction of fish or other living resources is illegal.” According to the Marine Conservation Institute, only 3.6 per cent of the world’s oceans – 2.4 per cent in strict no-take zones – is protected by 11,169 implemented MPAs. In Southeast Asia , there are many challenges in implementation of these sanctuaries attributed to the lack of resources, often limiting their size, number and management capability. According to SDG Plus, the top challenges for creating MPAs in the world include poor prioritisation of marine areas to protect; faulty implementation of protection measures; unequal distribution, with developed countries leading in the creation of MPAs; and, loss of income for the local communities because of the creation of no-take zones. In addition to contributing to biodiversity conservation, an important role of protected areas is to promote peace and cooperation. This is particularly true with transboundary protected areas or peace parks, which can be used to solve border disputes , secure or maintain peace during and after an armed conflict and promote stable and cooperative relationships between neighbouring states. How Chinese money plugged the Mekong, and SE Asia’s lifeblood In a regional sea with complicated territorial and maritime disputes like the South China Sea, the development of a regional network of MPAs with marine peace parks as components offers the possibility of decreasing tensions and enhancing cooperation between claimants. From a political point of view, cooperation in MPAs in a disputed area might be accepted by relevant claimants more easily than in other issues. Unlike oil and gas exploitation and fisheries, the development of a regional network of MPAs does not require any type of commercial extraction and sharing of marine resources. There are policy advances derived from cooperative marine science projects, which offer benefits from the establishment of new MPAs in the South China Sea. For instance, at the regional level, a first common fisheries resource analysis relating to skipjack tuna in the South China Sea was completed in September 2022 with the support of the Centre for Humanitarian Dialogue and the participation of fisheries scientists from China, the Philippines, Malaysia, Indonesia and Vietnam. The report concluded that current fishing levels of adults skipjack tuna are probably sustainable in most parts of the South China Sea. However, there is a risk of overfishing younger tuna . In addition, the Ocean Risk and Resilience Action Alliance is establishing a blended finance facility with Blue Finance to implement sustainable, revenue-generating initiatives in pilot programmes planned in Indonesia and the Philippines. At the bilateral level, the Philippines and Vietnam plan to resume their joint oceanographic and marine scientific research expedition in the South China Sea. This collaboration ran from 1994 to 2007 and helped acquire important data about the alarming decline in coral reefs and reef fish in the South China Sea. The second phase could include additional participants such as China and other Southeast Asian coastal states, which could translate into more data for a South China Sea-based network of MPAs. These projects are stellar examples of the compliance with Article 242 of the UN Convention on the Law of the Sea that asks states and international organisations to promote international cooperation in marine scientific research for peaceful purposes. While there remain plenty of obstacles for regional marine scientific research cooperation, the prospects for networked MPAs could ensure peace-building and a surplus of goodwill and a fish savings account for future generations. James Borton is a senior fellow at Johns Hopkins/SAIS Foreign Policy Institute and the author of Dispatches from the South China Sea: Navigating to Common Ground. Vu Hai Dang is a research fellow at the Diplomatic Academy of Vietnam.