Navigation and Seamanship (1+1)

6.1.4. Fishing with sonar

The echosounder indicates the bottom of the sea and fish under the vessel, the sonar can search a whole area, horizontally, in all directions. Further, it can be adjusted to any angle by tilting the transducer, or used vertically, for which purpose the transducer is moved into the same position as that of an echosounder. The sonar has mostly been used for pelagic fishing methods such as purse seining and mid water trawling. It is also quite useful for assessing bottom conditions and configurations, which are of interest for bottom trawling and other bottom fishing techniques.