Senkaku Islands See Surge in Chinese Patrols and Research Ships

Off Amami-Oshima in Kagoshima Prefecture, authorities recently observed a Chinese marine research vessel crossing the Japan–China median line. At the same time, Chinese government vessels (CGV) continue their near-daily patrols around the Senkaku Islands, Ishigaki City in Okinawa Prefecture, underscoring Beijing's growing assertiveness across the East China Sea.

Given China's long-standing strategy of exerting steady pressure to advance its maritime ambitions, Japan faces increasing calls to bolster its monitoring and defense posture.

Second Chinese Survey Ship Detected

A Chinese government marine research vessel has again been spotted operating near Amami-Oshima, this time in Japan's Exclusive Economic Zone (EEZ) without prior consent.

According to the 10th Regional Coast Guard Headquarters (Kagoshima), the Xiangyanghong 22 was confirmed in the area on September 26. Beginning on September 28, it carried out multiple unauthorized surveys despite repeated radio warnings from the Japan Coast Guard (JCG) to cease activity.

Until October 6, the Chinese government vessel continued deploying pipe-like equipment into the waters off Amami, with further operations confirmed on October 11.

Masahiro Ichijo, former head of the 11th Regional Headquarters (Naha) and now managing director of the Japan Coast Guard Association, noted that Beijing's intent may be political rather than scientific. "China has long surveyed the seabed topography and geology in this area," he said. "It's likely they've already gathered all the data they need. This latest mission may well be a political signal."

In addition, data from the vessel-tracking site VesselFinder and JCG sources confirmed that another Chinese research ship, the Xiangyanghong 18, crossed the Japan–China median line near the Senkaku Islands, Ishigaki City, on October 1. It was later observed operating off the Danjo Islands in Nagasaki Prefecture on October 5.

With this, two Chinese government survey vessels were active simultaneously in waters near Japan, underscoring Beijing's sustained maritime push in the East China Sea.

Larger Vessels Enable Year-Round Patrols

China's operations around the Senkaku Islands have grown increasingly persistent and provocative. Since Japan nationalized the islands in 2012, CGVs have made regular incursions into nearby waters. Once unarmed, these official government ships are now routinely equipped with machine guns, reflecting a steady escalation in their capabilities.

In the past, Chinese vessels would typically withdraw during typhoons or rough seas. However, the expansion and modernization of the fleet have made it possible for them to maintain patrols regardless of weather conditions.

According to the Japan Coast Guard's 11th Regional Headquarters, the current streak of continuous patrols is the longest on record. As of October 12, it had exceeded 300 consecutive days, with 328 days logged and a full year of unbroken presence now in sight.

National Spatial Plan

Analysts describe China's steady pressure in the East China Sea as its trademark salami-slicing strategy. Through a series of incremental, seemingly minor moves, Beijing gradually advances its attempted territorial control. Beijing employs the same tactic in the South China Sea, tightening its grip on disputed waters even in the face of international criticism.

China's sweeping National Spatial Plan, set for full-scale implementation in fiscal 2026, serves as a long-term blueprint for the strategic allocation of national resources. Experts caution that it could further entrench China's hegemonic ambitions in the East China Sea, particularly around the resource-rich Senkaku Islands.

Satellite imagery from the European Space Agency (ESA) has even detected discoloration in waters near the Japan–China median line off Amami, suggesting possible exploratory drilling activity.

"Heightened security vigilance is essential," warned Masahiro Ichijo.

Stronger Response

To counter the normalization of Chinese government patrols around the Senkaku Islands, Japan has steadily reinforced its maritime infrastructure and security posture.

In the wake of the 2012 nationalization, the Japan Coast Guard's 11th Regional Headquarters in Naha was initially forced to rely on reinforcements from patrol vessels across the country. Since then, extensive upgrades have transformed the Ishigaki Coast Guard Office in Okinawa into the front-line base for Senkaku operations.

By 2016, two new large patrol vessels had been commissioned, establishing a 14-ship system dedicated exclusively to territorial defense around the islands. Today, with more than 600 personnel, Ishigaki has grown into Japan's largest coast guard station, surpassing even Yokohama in scale and operational capacity.

Expanding Budget and Capabilities

Despite Japan's efforts to strengthen its defenses, China continues to expand and heavily arm its official government fleets. In response, the Japan Coast Guard has submitted a record budget request of ¥317.7 billion JPY (approximately $2.1 billion USD) for fiscal 2026. The proposal includes funding for two new large patrol vessels and improved coordination with the Ministry of Defense and other relevant agencies.

To reinforce Japan's position in maritime boundary disputes and counter unauthorized Chinese research activities, Tokyo also plans to upgrade its oceanographic survey technology and related equipment. These measures aim to enhance Japan's capacity to monitor, respond, and assert its maritime rights with greater precision and resilience.

(Read the article in Japanese.)

Author: Ryo Nishiyama, Naoki Otake, The Sankei Shimbun