Abstract
The preferred direction of attempted directional swimming of eels in experimental circular tank was investigated. Observation on stationary eels revealed 2 main preferred directions: north and south. The direction east was always the most neglected. In migratory eels from distant inland localities directional preference was found to be the same as in stationary eels, though only at the beginning of the migration season. The marginally preferred direction was NW. Migratory eels caught close to the North Sea during the high season of migration preferred mostly the direction north; marginally preferred were also the directions NW and W. The most neglected was found to be the direction east.