WHERE IN THE WORLD ARE THOSE PESKY CABLESHIPS? BY KIERAN CLARK
A GLOBAL ANALYSIS OF CABLE SHIP PATTERNS, INFRASTRUCTURE PROXIMITY, AND PROJECTED ACTIVITY USING AIS DATA
T
he global subsea cable network depends on a small, highly specialized fleet of installation and repair vessels whose work typically remains out of public view. AIS (Automatic Identification System) signals provide the only globally consistent window into this fleet’s behavior—but AIS reveals position, not purpose. Inferring mission profiles requires combining AIS tracks with known infrastructure locations, observed clustering patterns, and a model that interprets idle behavior in context. This updated analysis presents the latest geospatial results for November 2025, incorporating more than 9,200 AIS-derived idle points logged at sixhour intervals throughout the month. Compared to the September dataset, the November results show clear shifts: stronger clustering around East and Southeast Asia, noticeable increases in depot-linked maintenance signatures, and a continued surge in unclassified idle behavior. These shifts align with both seasonal repair cycles and the ongoing expansion of new-build activity across Asia. As in previous reporting, idle points—instances where vessels remained slow-moving or stationary long enough to indicate operations—were classified using a proximity-based model: • Installation when idling occurred near a cable factory • Maintenance when idling occurred near a cable depot • Unclassified when no facility proximity or vessel movement patterns provided sufficient context A 50 km threshold was used to associate vessels with facilities, with installation prioritized when both factory and
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depot fell within range. This mirrors behaviors observed in factory-adjacent staging zones, where vessels routinely load cable before deployment. This methodology continues to parallel approaches used in other mobility-driven industries—logistics, offshore energy, and fisheries—where positional dwell time and clustering are used to infer mission purpose. The goal remains the same: turning raw geographic data into operational insight when direct reporting is unavailable.
GLOBAL MAP OF OBSERVED BEHAVIORS
Figure 1 presents an updated geospatial view of cable-ship idling for November 2025, incorporating several thousand AIS-derived idle points across all major cable-serving