Chinese research ships linger over Taiwan's and Japan's undersea cables

The ships traced irregular courses north of Taiwan, along its east coast and in the Bashi Channel to the south. They include the Xiang Yang Hong 22, operated by the Ministry of Natural Resources, and the Tongji, belonging to a university in Shanghai. According to Seoul Economic Daily, 24 undersea cables pass near Taiwan, 14 of them international. The stopping points coincide with lines linking Taiwan to Japan, the US, Singapore and the Philippines.

The same firm has detected ships tied to a Chinese university carrying out similar manoeuvres since 2024 in Japan's exclusive economic zone, east of Hokkaido and off Nagoya. On 9 October Takaichi described the cables as indispensable critical infrastructure, and the government included a cable protection item in its budget request for fiscal 2027. Taiwan has averaged 7–8 cable incidents a year in its coastal waters over the past four years.

The limits of the evidence are clear: it could not be verified that the ships collected cable data. The analysis relies on tracks from the automatic identification system (AIS), the positional broadcast that ships transmit. A deputy minister at Taiwan's Mainland Affairs Council said on 2 November that China could make more frequent use of non-military vessels. Hu Xijin, the former editor of Global Times, wrote on Weibo that the marine data could serve defensive purposes.