What is the shadow fleet?
The shadow fleet, also called the dark fleet, describes ships associated with opaque ownership and shipping practices used to evade sanctions or other maritime requirements. It is a descriptive term, rather than one universally agreed vessel register.
The International Maritime Organization’s discussion of shadow fleet tankers identifies concerns including ageing ships, unclear ownership, inadequate insurance and increased risks of collisions and oil spills. These characteristics require evidence from several sources; a ship’s age or flag alone is not enough to classify it.
What is the Russian shadow fleet?
In discussion of Russia’s oil trade, the term refers to vessels and the operators behind them that support oil transport using opaque or high-risk practices associated with sanctions circumvention. The Council of the EU’s sanctions overview explains how its measures address shadow fleet shipping and related maritime risks.
A sanctions designation and an analyst’s shadow fleet classification answer different questions. Designations come from particular authorities and programmes; a research watch list may use additional criteria. Always check which list a vessel appears on and the basis for that entry before drawing conclusions from a map marker.
How can you track a shadow fleet vessel?
Shadowfleet.watch brings vessel search, received AIS positions and recorded observations into one map. A useful investigation starts with the ship’s identity and the observation time, then works outwards to its track and surrounding traffic.
- Find the ship. Search the vessel list by name, IMO number or MMSI. Use the IMO as the reference when comparing records across name changes. The tracker groups watch list matches by IMO and records changes to associated AIS identity information.
- Check when it was observed. A marker is a received position, not a guarantee of the vessel’s current location. Review the last observation time and the feed status before interpreting movement.
- Inspect the available track. Replay recent observations and compare the vessel with nearby traffic. A gap in recorded positions leaves the intervening route unknown.
- Open the event evidence. A recorded event has a shareable page with measurements, participating vessels and available track samples. Keep its link and timestamp when discussing the observation.
- Cross-check the explanation. Compare the cited list entry and other independent evidence with the map. The event definitions explain what triggered each observation and what it can establish.
Does an AIS gap mean a ship is hiding?
AIS is a radio system that shares vessel identification, position, course, speed and other information. The IMO’s AIS overview describes its navigational purpose and carriage requirements. A public tracking service only shows reports that reach its receiving network.
An absence of reports can reflect reception gaps, equipment or data delivery problems, or a transmitter no longer being observed. The map alone cannot establish the cause. Shadowfleet.watch uses reception history to give gaps context and pauses new gap detection during broad feed interruptions.
On an event page, tracks stop across long gaps rather than drawing a continuous voyage through missing observations. A returning position can establish separation from the last sighting, but not the path taken between them.
What do encounters and infrastructure alerts show?
A sustained close encounter can be a useful lead when researching possible ship-to-ship activity. The tracker records proximity, reported speed and duration. Those observations do not identify a cargo, measure a transfer or establish whether one took place.
For Baltic Sea monitoring, the map also includes subsea cables, pipelines and power links. Infrastructure proximity events show the named reference route alongside vessel tracks. Some routes are approximate, and the line shown comes from the current reference dataset. Proximity by itself does not demonstrate contact, anchor dragging or damage.
Which ships does Shadowfleet.watch cover?
Shadowfleet.watch is an independent tracking project at shadowfleet.watch. Its watch list uses sanctions data from the OpenSanctions maritime collection, together with curated additions. It covers multiple sanctions programmes, so the list is broader than Russian oil tankers and should not be treated as a complete global shadow fleet count.
A listed vessel may have no received AIS position. Conversely, nearby ships can appear as encounter counterparts without belonging to the watch list. The distinction is shown in vessel profiles.
General replay uses five days of raw position history. Recorded events are retained, and available event track samples are archived separately. Observations that expired before archiving began cannot be recovered. Read the full methodology and data sources before using the results in research or reporting.