actively stimulating fish behaviour
to improve escape panel selectivity
Target species:
Norway lobster, cod
Area, Vessel
The study was carried out in 2013 in the North Sea and Western Skagerrak on board the commercial twin-trawler HM 128 Borkumrif (28 m and 728 kW).
Norway lobster, cod
Area, Vessel
The study was carried out in 2013 in the North Sea and Western Skagerrak on board the commercial twin-trawler HM 128 Borkumrif (28 m and 728 kW).
Gear type:
demersal
Gear modification
The standard gear was a 90 mm diamond mesh codend with a 270 mm diamond mesh escape panel positioned 4-7 m from the cod-line. The experimental gear was identical but with a stimulation device. The stimulation device was made from three 3.4 m long ropes. Each rope had one 20 cm float in the middle and three smaller oval floats placed 40 cm apart on either side. The float ropes were only fixed to the lower netting in the four panel section to allow the passage of seaweed and litter. To compensate for the extra flotation three leaded lines were mounted below the string of floats. It was hoped that the line of floats would stimulate cod to escape through the large mesh panel.
demersal
Gear modification
The standard gear was a 90 mm diamond mesh codend with a 270 mm diamond mesh escape panel positioned 4-7 m from the cod-line. The experimental gear was identical but with a stimulation device. The stimulation device was made from three 3.4 m long ropes. Each rope had one 20 cm float in the middle and three smaller oval floats placed 40 cm apart on either side. The float ropes were only fixed to the lower netting in the four panel section to allow the passage of seaweed and litter. To compensate for the extra flotation three leaded lines were mounted below the string of floats. It was hoped that the line of floats would stimulate cod to escape through the large mesh panel.
Results:
By actively stimulating escape behaviour the number of cod escaping through square mesh panel can be increased. The float ropes did not effect the catches of Nephrops.
By actively stimulating escape behaviour the number of cod escaping through square mesh panel can be increased. The float ropes did not effect the catches of Nephrops.
Further information:
Jordan Feekings (jpfe@aqua.dtu.dk) Krag et al., 2016. Improving escape panel selectivity in Nephrops directed fisheries by actively stimulating fish behaviour. CJFAS, 10.1139/cjfas-2015-0568
Jordan Feekings (jpfe@aqua.dtu.dk) Krag et al., 2016. Improving escape panel selectivity in Nephrops directed fisheries by actively stimulating fish behaviour. CJFAS, 10.1139/cjfas-2015-0568
Citation :
Krag, L.A. et al.
, 2017.
actively stimulating fish behaviour
. In O’Neill, F.G. and Mutch, K. (Eds): Selectivity in Trawl Fishing Gears. Scottish Marine and Freshwater Science Vol 8 No 1.