China’s presence at Scarborough Shoal in South China Sea ‘unprecedented’ in 2025: report

China significantly intensified its South China Sea patrols in 2025, maintaining an “unprecedented” nearly year-round presence at contested sites like Scarborough Shoal to assert maritime claims, according to a new US-based think tank report.

An analysis published on Thursday by the Asia Maritime Transparency Initiative (AMTI) – a research programme affiliated with the Centre for Strategic and International Studies – showed a substantial increase in China’s patrol presence as well as a broadening of its patrol coverage near Scarborough Shoal and Sabina Shoal.

The AMTI’s analysis drew on data from the Automatic Identification System, a tracking system that uses transponders on ships to provide real-time information to other vessels, coastal authorities and satellites.

It employed two metrics to quantify the Chinese coastguard’s (CCG) presence: ship days, which represent the total sum of days spent by every individual CCG vessel at a location, and calendar days, which refer to the number of distinct days in a year during which at least one CCG ship was present.

According to the institute, the Chinese coastguard achieved a nearly year-round presence near Scarborough Shoal, with patrols observed on 352 calendar days.

South China Morning Post