Abstract

The Port State Measures Agreement (PSMA) provides a legally-binding mechanism to deter illegal, unreported and unregulated (IUU) fishing by foreign vessels through standardized reporting, inspections, information sharing, and port denial. To be more effective, region-wide 25 adoption and consistent implementation of PSMA are essential for ensuring IUU fishing vessels cannot easily land catches with identities that will receive less scrutiny or in locations with weaker governance. The PSMA also recognizes the centrality of tackling IUU fishing in domestic fleets, which account for more than 90% of port visits. Port State measures aligned with PSMA need to be applied to these fleets to prevent the flag-switching that allows vessels to 30 dodge oversight. Accelerating adoption and implementation of PSMA as well as extending port State measures to domestic fleets is crucial for reducing opportunities to hide illegal catches and maximize the potential of actions at port to address IUU fishing. One-Sentence Summary: Reducing IUU fishing risks will depend on consistent, regional 35 implementation of effective port State measures across both foreign and domestic fleets.