In collaboration with shipbuilder Jaczon BV and the American sonar supplier Farsounder Inc, TNO has developed a system to differentiate various species of pelagic fish (herring, mackerel, horse mackerel and sprat). Using a broadband forward-looking sonar, fish can be categorised in real-time, which enables the minimisation of a significant amount of undesired by-catch in the pelagic fishing sector. As part of the “Sonar for Fish Classification” (SOFIC) project, TNO has developed and successfully tested a prototype. New sonar data can help to constantly improve this TNO algorithm for fish recognition.

The incidence of undesired by-catch is becoming an increasing challenge to the fishing sector, and the pressure to reduce it is growing with the introduction of new European legislation, namely the catch landing requirements that stipulate that by-catch may no longer be thrown overboard while current regulations state that this must be done for non-quota and undersized fish. This means that throughout the sector there is a growing need to fish more selectively.


For Schevening-based shipbuilder Jaczon BV (part of Cornelis Vrolijk), sustainable fishing and business have always been central to its operation. So it is an important objective of the shipbuilder to collaborate on sustainable management of pelagic fishing, including the maintenance of healthy ecosystems. “Selective fishing is one of the possible solutions in which Jaczon BV is investing to achieve its aims for sustainable fishing.” Selective fishing means that only the required fish species and sizes are recognised and caught. TNO is contributing its unique sonar knowledge to make this possible,” says Eric Roeleveld, Operations Manager of Jaczon BV.