Improved catch on cod (Gadus morhua), haddock (Melanogrammus aeglefinus) and Greenland halibut (Reinhardtius hippoglossoides) with a new hauling technique in the Norwegian mechanized bottom longline fishery

摘要

A new hauling method was tested and compared to conventional hauling techniques in the Norwegian mechanized longline (autoline) fishery in April and May 2007. The 51-m-long Norwegian combined gillnetter-longliner M/V "Loran" currently is the only vessel that has a hauling well mounted in the side of the vessel. The line is hauled through an adjustable hatch at the waterline. The well is 3-m high, 2-m long, and 1.5-m deep and is equipped with a conveyor belt that carries fish up to the hauler room. In total, we used 99 2-h series of data collection to compare the hauling methods. The new technology increased the catch significantly: 2.3% for cod, 6.2% for haddock, and 8.8% for Greenland halibut. The new hauling technique reduces hard labour for the crew because no gaff is needed and fewer fish are lost. The results and possible advantages of this technology are discussed in view of responsible fishing techniques.