Blue crab sparking an international incident? Sounds unlikely, but it is a perennial problem between China and South Korea at this time of year in the waters around the Korean Peninsula. Earlier this month, two Chinese fishing boats were seized by the Republic of Korea (ROK) maritime police after South Korean fishermen found them illegally fishing off Yeonpyeong Island in the Yellow Sea. Frustrated by illegal fishing, the South Korean fishermen had taken matters into their own hands and captured the Chinese boats before turning them over to the ROK authorities.

Just days later, on June 10, South Korean naval and marine forces carried out an operation with the United Nations Command (UNC) to repel Chinese vessels illegally fishing in the mouth of the Han River estuary near the disputed maritime border between the two Koreas. Although this appears to be first time the UNC has participated in such an operation since the Korean War, the U.S.-led command was involved because certain provisions of the 1953 Korean War Armistice Agreement cover the territory of the Han River estuary. The UNC has authority to police the southern part of the Military Demarcation Line (MDL) under the armistice and the operation was conducted within this demilitarized zone. This area is near but not on the disputed Northern Limit Line (NLL) between the two Koreas.

This is not the first time that Chinese vessels have clashed with South Korean military and police forces over illegal fishing in the Yellow Sea. According to the South Korean Ministry of Defense, Chinese fishing boats were found to be illegally operating in the area approximately 120 times in 2015 and 520 times in 2016 (as of May). More deadly clashes resulted in the death of a Chinese fishing boat captain in 2014, the killing of a member of the ROK coast guard in 2011, and the deaths of two Chinese fishermen in 2010.

Disputes been China and South Korea over illegal fishing in Korean coastal waters have been a growing problem since the early 2000s. According to the 2013 ROK Coast Guard White Paper, more than 2,100 illegal fishing boats and 540 fishermen were caught in South Korea’s exclusive economic zone (EEZ) between 2008 and 2012. Recent news reports cite even higher numbers. But this is not a simple bilateral matter between China and South Korea. The situation is complicated by overlapping maritime disputes and competing territorial claims in both the Yellow Sea and East China Sea.

Most relevant to the recent incidents between Chinese fishing vessels and ROK naval and marine forces is the NLL dispute between the two Koreas. Chinese fishermen often enter into fishing contracts with North Korea and then illegally cross the NLL to fish in South Korean waters. The long-standing conflict over this de-facto maritime border provides Chinese fishermen with an opportunity to continue their illegal fishing practices because of fears that actions against them could spark a military confrontation between North and South Korea. They take advantage of the fact that control of the waters around the five Northwest Islands in the armistice agreement and the area between the extended MDL and the NLL is disputed. In fact, Chinese illegal fishing is not just a persistent problem in South Korean-controlled waters, but in those patrolled by North Korea as well. The convergence of complicated trilateral interests between China, South Korea, and North Korea makes the maritime disputes difficult to resolve and ripe for further conflict.

The NLL dispute is unlikely to be resolved anytime soon and if anything appears to be getting worse since North Korean leader Kim Jong-un came to power in late 2011. Adding fuel to the fire is the fact that the applicable legal regimes are a tangled web of international law, bilateral fishing accords, the armistice agreement, and private fishing contracts. And even if the applicable law were clarified, the enforcement of maritime rules and norms would remain ineffective and spotty at best.

The NLL is perceived as an exclusively inter-Korean dispute not easily resolved through international law. The UN Convention on the Law of the Sea (UNCLOS) might technically apply to this dispute if Pyongyang eventually ratifies the convention, but neither South nor North Korea now recognizes it application as such. Settling this inter-Korean conflict using UNCLOS and its dispute resolution mechanisms could disadvantage one side or the other, which is a risk neither seems willing to take.

The Agreement on Fisheries between the Republic of Korea and China, signed in 2000, does not provide a good mechanism for resolution of the illegal fishing problem. The agreement is ambiguous with respect to illegal fishing in the area around the NLL and has no dispute settlement clause. China and South Korea are parties to UNCLOS, but even in the unlikely case that both agreed to submit to the convention’s dispute settlement processes and the issue was covered by the treaty’s provisions, the overlapping dispute with North Korea would likely make a resolution impossible.

Given that this problem is not easily resolved through legal means, the South Korean government should seek to address the problems that contribute to illegal Chinese fishing through diplomatic and political mechanisms. The ROK government should use both bilateral and multilateral means to encourage the Chinese government to tackle this issue more forcefully. The primary causes for the increase in illegal Chinese fishing activity include:

  1. Depletion of fish stocks in China’s coastal waters due to pollution and overexploitation of fishery resources;
  1. Growing demand for seafood in China, which allows Chinese fishermen to earn greater profits, increasing the incentives for illegal and aggressive fishing;
  1. Poor understanding of applicable maritime laws combined with traditional fishing practices, leading some Chinese fishermen to believe they have fishing privileges in Korean waters;
  1. Fear of accidental inter-Korean military confrontation in the grey zone around the NLL;
  1. Failure of diplomatic pressure to convince the Chinese government to police its own fishing vessels, combined with South Korea’s limited resources to effectively guard against illegal fishing.

To address these problems the South Korean government should:

  1. Work with China and its neighbors to reduce pollution and resupply fishery stocks in Chinese coastal waters. This could include more active enforcement of environmental treaties, norms, and regulations, increased participation in regional bodies dealing with these issues, and technical exchanges between Chinese and Korean experts.
  1. Encourage multilateral cooperation between other countries affected by illegal Chinese fishing practices, including Indonesia, Japan, the Philippines, and Vietnam.
  1. Create education programs for Chinese fishermen that include lessons about the dangers of operating near the NLL and the risks of illegal fishing.
  1. Strengthen efforts to improve emergency communication channels and confidence building measures between North and South Korea to lessen the possibilities of military confrontation. These could include establishing naval hotlines, implementing common radio frequencies for ships, and creating shared signals that demonstrate intent of vessels in disputed maritime regions.
  1. Explore the possibility of enlisting a neutral body to offer policy recommendations to regional governments on maritime disputes in the Yellow and East China seas.

Continue to meet with Chinese government representatives twice a year to address fisheries cooperation between the two countries, discuss ways to address some of the ambiguities and weaknesses of the applicable legal regimes, and allay Chinese concerns about disproportionate responses to the illegal fishing problem.

About Lisa Collins

Lisa Collins was a fellow with the CSIS Korea Chair. Prior to joining CSIS, she worked for seven years as a program officer at the Asan Institute for Policy Studies in Seoul, Korea. Her research interests include U.S.-ROK relations, nuclear nonproliferation and disarmament, human rights and refugee law, transitional justice, Northeast Asian security, and the intersection between international law and international relations.