Port governance after offshore risk: overseas receiving corridors in China’s distant-water fishing

IntroductionIllegal, unreported, and unregulated fishing is governed across a chain that extends from offshore activity to port entry and downstream handling. Existing research has advanced offshore detection, vessel mobility analysis, and port-state governance, yet less is known about whether signal-bearing trajectories first return to dominant domestic ports or reappear in a smaller set of overseas receiving ports.MethodsUsing China’s distant-water fishing as a diagnostic case, we link event-level AIS gap signals to thefirst subsequent port call and benchmark those trajectories against routine port use and a same-quarter/type reference layer in the same quarterly windows. The design combines a corrected gap-event rebuild (12,229 events; 3,220 vessels), a routine comparison layer (40,000 confidence-4 port visits), full risk-pool tracing, 180-day first-post-gap linkage, and quarter- and vessel-type matched non-risk benchmarks.ResultsEvent-level linkage is observable for 4,149 of 12,229 corrected gap events (33.9%), and all routing conclusions are conditional on that linked layer. Within it, Chinese ports receive 98.95% of routine baseline visits and 98.70% of matched-benchmark visits; after gap events, Chinese ports account for 37.14% of first receiving links. Foreign first receiving ports concentrate follow-up work in a recurring corridor set, with Korea, Chile, and Fiji accounting for 57.7% of foreign first links.DiscussionThe sharpest divergence appears at first port re-entry. Signal-bearing trajectories often first reappear outside the dominant domestic chain, before later post-gap movement is counted. These first receiving ports mark where offshore signals can first meet port services, document checks, notification channels, and inspection prioritization in the observed trace layer.