Monthly Patrol Days of Chinese and Philippine Vessels Near Scarborough Shoal

Chinese patrol presence consistently exceeds that of the Philippines from August 2024 to May 2025, with a sharp peak in January.

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• “Patrol Days” refer to the total number of calendar days a vessel spends within the designated observation area. A patrol is considered to begin when a vessel enters the defined zone and to end when it exits. All calendar days between the entry and exit dates (inclusive) are counted as Patrol Days.

Chart: CSIS/AMTI Source: Starboard Maritime Intelligence Get the data Created with Datawrapper