- Loitering is when a single vessel exhibits behavior indicative of a potential encounter event. Loitering is also estimated using AIS data, including vessel speed, duration in a given location, and distance from shore.
- Loitering occurs when a carrier vessel travels at average speed of < 2 knots, while at least an average of 20 nautical miles from shore.
- It is possible that loitering events do not indicate a potential transshipment, but another event in which a vessel may remain fairly steady, including maintenance or waiting outside of port for permission to dock
- Due to the individual definitions of loitering events and encounter events, it is possible for a loitering event to overlap with encounter events and to encompass one or more encounter events.
For both encounters and loitering events the duration can be filtered between 1 hour and greater than 48 hours based on user preference. This filter can enable a user to restrict possible transshipment events to those they consider more likely based on knowledge of duration of transshipment events.