The 35 reefers

This map shows 35 large refrigerated cargo ships (reefers) operating in 2013 in western African waters:

  • Each orange spot marks a point where the ship has emitted a signal.
  • A high density of signals generates a hotspot, identified by a circle. This marks a point where the ship has either switched off its engine or has reduced its cruising speed to a maximum of 1 knot (1 UK nautical mile/hour). This visualisation includes only hotspots at a minimum distance of 6 nautical miles from any port.
  • Each country's Exclusive Economic Zone (EEZ) border is marked by a thin grey line.Transhipment (moving catches from small fishing boats to reefers) in the EEZs of Senegal and Côte d'Ivoire is prohibited.
  • A reduced number of reefers, for example Izar Argia, are lacking in good enough signals for brief periods of time, in a way that their itineraries seem to cross over some peninsulas' tips by land.
  • The Meltemi's and Dolly 798's AIS signals have not enough quality to show a coherent pattern, so the authors decided not to include them in the visualisation.

What are we looking out for?

  • Straight lines and uniform, regular tracks indicate that ships are crossing an EEZ at cruise speed.
  • A higher frequency of hotspots and an erratic track pattern indicates that ships are operating in a specific area – and potentially seeking out fish transhipment business. (Sometimes however a hotspot is generated by the vessel simply waiting for instructions and changing direction, which is a normal manoeuvre.)

Select a Vessel

Tracking history


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