Catch comparison trials of the flip flap netting grid trawl

Authors: 

Drewery, J., Watt, M., Kynoch, R.J., Edridge, A., Mair, J. and O'Neill, F.G.

Year: 

2012

Journal/Publisher Name: 

Marine Scotland Science Report

Volume (Issue #): 

08/12

Page #s: 

16

Contact information: 

Marine Scotland Science, Marine Laboratory, 375 Victoria Road, Aberdeen, AB11 9DB
Summary: 

At sea trials were conducted comparing the catch composition and weight of standard Nephrops scraper trawls and a new trawl termed the Flip Flap netting Grid trawl (FFG).  The FFG includes a 160 mm mesh size netting in the top wing and top sheet netting panels, flip-flap netting grid, and fish outlet hole and 200 mm square mesh panel fitter in front of the fish outlet hole. The FFG trawl resulted in a ~30% reduction (number) of small cod around 32 cm in length but not in fish smaller than this.  A 33% reduction was seen for cod sized 35 cm and a 76% reduction for cod 87 cm in size.  In addition, there was a 73% reduction in cod by weight.  For haddock, there was a 51% reduction of haddock around 21 cm, 67% for fish 30 cm in size (MLS) (and weight), and a 73% reduction for fish 44 cm in size.  For the smallest whiting (26 cm) there was a 62% reduction, at the MLS (27 cm) there was a 64% reduction and for 48 cm fish an 84% reduction. By weight, there was an 82% reduction.  Catches of Nephrops were similar for the two gear types.