PRC Research Vessels Nearly Double Survey Time Around Taiwan in 2026

In 2026, Chinese research vessels near Taiwan nearly doubled their survey time compared to the previous year, according to Windward MIOC analysis of 52 vessels. The northern South China Sea saw a shift in fleet working time, with slow-speed survey and station work off Taiwan rising from 3,862 to 7,411 hours between January and September 2026.

This increase coincides with China's 2019-25 plan to boost domestic oil and gas production. The rise in survey time around Taiwan is primarily due to China Geological Survey and academic vessels, accounting for 78% of the additional time, mainly working over offshore oil, gas, and gas-hydrate areas. This trend was observed on both Taiwan's and the mainland's sides, with the fleet working time remaining relatively constant.

The increased activity appears to be concentrated around Japan's southwestern islands, where slow-speed working time rose about eightfold. Additionally, near Guam, the fleet adjusted its approach rather than leaving slow-speed work behind, as one vessel's role in deep-sea dives to Challenger Deep came to an end, leading to a switch to faster seabed mapping around Guam.

The source acknowledges that it is too early to determine if the 2026 increase around Taiwan reflects a recurring field program or a sustained reallocation of effort. More data from the winter and spring of 2027 will help clarify this distinction. The data reveals a diverse range of missions conducted by the fleet, including resource survey, academic oceanography, hydrothermal research, polar science, and defense-industry testing.

These various activities are supported by repeated measurements along fixed lines east and south of Taiwan, which aid in underwater acoustic modeling and research. Monitoring the fleet's activities will prove more informative than simply counting the presence of research vessels alone.