Project aim: access any losses to the catch when using the Swedish Grid
In 2009 BIM conducted further trials in the Irish Sea on the use of this selective fishing method. We access any losses of prawns (Nephrops) and marketable fish when using the grid.
Our methods: trials with industry
Our observer was onboard the mfv ‘Matter Dei’ in Area VIIa during two, three day fishing trips.
The trials were conducted using a twin-rig catch comparison with one trawl rigged as standard and the other with a Swedish Grid.
Our observer:
- weighed all catches of Nephrops and marketable fish during normal commercial fishing activity and
- noted any issues with the performance and onboard handling of the grid
It was necessary to increase floatation at the top of the
grid to prevent it sinking into the soft mud of the Irish Sea.
The Grid got blocked by crab, seaweed and other
marine debris during the trawl which may have affected the catch.
Seeing the benefits: loses to the Nephrops catch minimised
Some losses to the catch when using the grid were observed, however, adoptions made to the floatation of the gear indicated that loses could be minimised.
The use of the Swedish Grid significantly reduces by-catch of cod allowing the important prawn fishery to continue while rebuilding the Irish Sea cod stocks.
The effectiveness of the grid is apparent in this example of
clean Nephrops from a grid trawl
Potential for further improvements:
Adjustments to the installation of the grid could also be of benefit.