Scarborough Shoal

Scarborough Shoal, also known as Bajo de Masinloc in the Philippines and Huangyan Dao in China, is a disputed maritime feature located in the South China Sea. It consists of a small group of rocks and reefs surrounding a large lagoon, and it has become one of the focal points of territorial tensions in the region due to its strategic location, resource potential, and political symbolism.

Geographical Setting

Scarborough Shoal is situated approximately 220 kilometres (137 miles) west of Luzon Island in the Philippines and about 800 kilometres (500 miles) southeast of China’s Hainan Island. The feature lies within the eastern part of the South China Sea, near the entrance to the Luzon Strait, which connects the South China Sea with the Pacific Ocean.
The shoal is roughly 150 square kilometres in total area, consisting of a triangular chain of reefs and rocks enclosing a lagoon about 15 kilometres in diameter. The lagoon, with depths ranging from 10 to 20 metres, provides excellent anchorage for small vessels. However, the surrounding reefs are mostly submerged at high tide, with only a few rocks permanently above sea level.
Geologically, Scarborough Shoal is part of a coral atoll formation, built by biological and sedimentary processes on a volcanic base. The area supports a variety of marine life, including corals, fish, and shellfish, making it important for local fishing communities.

Historical Background

Historically, Scarborough Shoal has been visited by fishermen from neighbouring regions for centuries, particularly from the Philippines and China. The name Scarborough Shoal originates from the British East India Company ship Scarborough, which ran aground on the reef in 1784.
During the Spanish colonial period, the shoal was recognised by Spanish navigators and appeared on maps as Bajo de Masinloc, a name derived from the nearby Philippine coastal town of Masinloc in Zambales province. When the Philippines came under American administration in 1898, maps and records continued to include the shoal as part of Philippine territory.
China’s claim to the shoal dates back to historical maps and records referring to it as Huangyan Dao, allegedly used by Chinese fishermen since the Yuan Dynasty. However, international records of consistent Chinese administration or occupation before the 20th century remain limited.

Strategic and Economic Importance

Scarborough Shoal holds significant strategic and economic value in the South China Sea. It is located near vital international shipping routes through which a large proportion of global trade passes. Control over the shoal provides a potential naval and surveillance advantage, allowing oversight of maritime traffic entering or leaving the South China Sea.
Economically, the surrounding waters are rich in fishery resources, which are crucial for coastal livelihoods in the Philippines and neighbouring countries. Moreover, the broader South China Sea is believed to contain substantial reserves of oil, natural gas, and other marine resources, adding to the importance of territorial control over features like Scarborough Shoal.

The Territorial Dispute

The sovereignty of Scarborough Shoal is contested primarily between the Philippines and China, though Taiwan also maintains a similar claim as part of its broader South China Sea assertion.

• Philippine Claim: The Philippines bases its claim on proximity, historical usage, and its inclusion within the country’s Exclusive Economic Zone (EEZ) under the United Nations Convention on the Law of the Sea (UNCLOS). The shoal lies well within 200 nautical miles of Luzon and has long been used by Filipino fishermen.
• Chinese Claim: China claims “historical rights” over the shoal as part of its nine-dash line, a demarcation that encompasses nearly the entire South China Sea. China asserts continuous fishing and administrative presence since ancient times.
• Taiwan’s Claim: Taiwan mirrors China’s claim, citing the same historical reasoning.

Tensions escalated in April 2012, when a standoff occurred between Philippine and Chinese maritime vessels after Philippine authorities attempted to arrest Chinese fishermen for illegal fishing within the shoal’s lagoon. China subsequently deployed government ships and took de facto control of the area, effectively barring Filipino fishermen from entry.

The 2016 Arbitration Ruling

In 2013, the Philippines initiated legal proceedings against China under the dispute settlement provisions of UNCLOS, leading to a landmark ruling by the Permanent Court of Arbitration (PCA) in The Hague on 12 July 2016.
The tribunal ruled that:

• China’s claim of “historical rights” within the nine-dash line had no legal basis under international law.
• Scarborough Shoal’s rocks and reefs do not qualify as islands, as they cannot sustain human habitation or economic life, and thus are entitled only to a 12-nautical-mile territorial sea.
• The Philippines’ sovereign rights within its EEZ, including fishing rights around Scarborough Shoal, were affirmed.

However, the PCA ruling could not be enforced directly, and China rejected the verdict, maintaining its presence and control around the shoal.

Current Situation and Developments

Following the 2016 ruling, diplomatic relations between the Philippines and China fluctuated. While the Philippine government under President Rodrigo Duterte initially adopted a conciliatory approach to improve bilateral ties, Chinese coastguard vessels continued to patrol the area, often restricting Filipino fishermen’s access.
In recent years, the situation around Scarborough Shoal has remained tense:

• Chinese coastguard and militia ships regularly patrol the area and have reportedly installed temporary buoys and barriers.
• Filipino fishermen continue to operate under limited conditions, often escorted by Philippine maritime authorities.
• The Philippine Coast Guard has periodically removed Chinese barriers and asserted its right to operate within the country’s EEZ.
• The United States and other international actors have reiterated support for the 2016 arbitration award and called for adherence to international law.

Environmental and Ecological Concerns

The shoal’s coral reefs have suffered significant degradation due to illegal fishing practices such as blast fishing and cyanide use. Reports indicate that both Chinese and local fishermen have contributed to reef damage, threatening the marine ecosystem and biodiversity.
The area is part of the broader Coral Triangle, one of the world’s richest marine biodiversity zones. Conservationists emphasise that the continued militarisation and exploitation of Scarborough Shoal risk long-term ecological harm.

Geopolitical Implications

Scarborough Shoal is a strategic flashpoint in the broader South China Sea dispute, involving not only sovereignty issues but also major geopolitical rivalries between regional and global powers. Its proximity to the Philippines, a treaty ally of the United States, makes it a critical location for defence and security planning.
Control of the shoal enables enhanced maritime domain awareness, potential radar installations, and influence over sea routes connecting the Pacific and Indian Oceans. The dispute reflects broader tensions over freedom of navigation, territorial sovereignty, and regional influence between China and the United States, with ASEAN nations caught in between.

Significance and Outlook

Scarborough Shoal remains one of the most contested maritime features in Asia. For the Philippines, it represents national sovereignty, livelihood security, and adherence to international law. For China, it symbolises historical legitimacy and regional authority.
Efforts to de-escalate tensions include bilateral dialogues, ASEAN-led negotiations, and calls for the early conclusion of a Code of Conduct in the South China Sea. Yet, the absence of mutual trust and the continuing militarisation of the region make long-term resolution challenging.