The Behaviour of Cod When Approaching and Entering a Pelagic Trawl
description
Transcript of The Behaviour of Cod When Approaching and Entering a Pelagic Trawl
![Page 1: The Behaviour of Cod When Approaching and Entering a Pelagic Trawl](https://reader038.fdocuments.in/reader038/viewer/2022110102/56813ddf550346895da7abb9/html5/thumbnails/1.jpg)
The Behaviour of Cod When Approaching and Entering a
Pelagic Trawl
Shale Rosen, Terje Jörgensen and Arill Engås
Insitute of Marine Research
Postboks 1870 Nordnes
N-5817 Bergen Norway
Nor-Fishing Technology Conference 2008
Trondheim, Norway 11-12 August 2008
![Page 2: The Behaviour of Cod When Approaching and Entering a Pelagic Trawl](https://reader038.fdocuments.in/reader038/viewer/2022110102/56813ddf550346895da7abb9/html5/thumbnails/2.jpg)
Research Question:
How do cod react to approach and passage of pelagic trawl?
Applications:
•Fishing strategy for efficient capture•Net design for efficient capture•Design and placement of selectivity devices
![Page 3: The Behaviour of Cod When Approaching and Entering a Pelagic Trawl](https://reader038.fdocuments.in/reader038/viewer/2022110102/56813ddf550346895da7abb9/html5/thumbnails/3.jpg)
Tracking Distinct Schools of Cod From Vessel to Extension of Net
Fish pass under vessel13:31:52
536 m in 328 sec 167 m in 105 sec
School in extension of net13:39:05
Same school enters mouth of net13:37:20
1.6 m/sec
Measured velocity through water:
1.6 m/sec
1.6 m/sec
![Page 4: The Behaviour of Cod When Approaching and Entering a Pelagic Trawl](https://reader038.fdocuments.in/reader038/viewer/2022110102/56813ddf550346895da7abb9/html5/thumbnails/4.jpg)
Calculations of Swimming Speed
sec
m 1.6
sec
m 1.6
WaterThrough Speed Trawl Time
Covered Distance Speed Swimming
sec
m 0
Cod in pelagic trawls do not appear to exhibit horizontal swimming behaviour!