Analysis of vessel traffic and safety assessment of the Soya Strait

In order to acquire the true figure of vessels going through the Soya (La Perouse) Strait, an AIS (Automatic Identification System) receiving station was set up in November 2008 and data has been successfully stored. Both static and dynamic analyses were conducted. First, the Strait was divided into eight sections and directions and the numbers of vessels crossing each section were counted. Second, the area was divided into 1 km square grids, then each grid was examined as to whether two or more ships were in the same grid at the same time. As a result from the first analysis, vessels are crossing both bounds of west to east and east to west in each section. Large vessels with hazardous materials are likely to be congested in the northern part of the strait to keep away from the Reef Nijo and save petroleum, and dangerous crossings have actually occurred periodically. Lane separation or other traffic regularity needs to be established through international cooperation.