Effects of a geophysical survey on catching success in longline fishing
Original version
This report is not to be cited without prior reference to the authorAbstract
The effects on longline catches of a geophysical survey conducted during the winter fishery
for cod (Gadus morhua) were studied. Spatial extent of the effects was investigated by
comparing the catch rates of longlines set at various distances from the survey tracklines, and
duration of the effects was studied by analysing the catch rates of longlines soaked after the
sound emissions ended. Catch reduction of 55-80% was observed for longlines set within the
seismic survey area. The results indicated that the acoustic device used caused a 24-h duration
and 5-miles spatial extent of reduced catches.