Trawl gear Technology and Trawl selectivity course

Seafish Training course at Sintef Flume Tank, Hirtshals on Trawl gear Technology and Trawl selectivity For fishery managers / researchers/ legislators on  Wednesday 24th and Thursday 25th February 2016

Course objectives

A - To familiarise the participants with a trawl gear rig and demonstrate relevant design features in relation to fish capture
B - To give a basic understanding of trawl gears used in UK fisheries and explain their respective catching mechanism 
C - To improve the understanding of exactly what the various selectivity devices are and how they work.
D - To discuss the pros and cons of each one in relation to different species and different fisheries.
E - To clarify any problems that the industry may encounter in using each device with reference to economics, handling on board, fitting and current regulations.

Suggested Course Timeline (this may be altered to include items of specific interest if possible and practical)

Wednesday 24th February:

8.45am   Assemble at Hirtshals flume tank
9.00 - 12.00 Flume Tank, working through schedule (see below)
12.00 - 12.45  lunch at North Sea Centre
12.45 - 16.00 Flume Tank, working through schedule (see below)

Thursday 25th February

8.30- 11.45 Flume Tank, working through schedule (see below)
11.45 - 12.00 Round up of course and thanks.
2.00 -   Lunch at North Sea Centre

If required it may be possible continue working at the flume tank in the afternoon to look at specific gears and selective devices requested by course participants.

Planned Flume Tank schedule

  1. Introduction to the Sintef Flume Tank. Mike Montgomerie (Seafish) and Kurt Hansen (Sintef)
  2. Demonstration of basic trawl - to demonstrate the various parts of a trawl and explain their purpose.  (Mike Montgomerie)
  3. Demonstration of some of the basic alterations that are made to a trawl. (9.30 - 10.15)
  4. Demonstration of trawls and selective devices commonly used in UK waters. (Mike Montgomerie)

Explanations of where the trawls are used, what species they are used to target and why they are rigged in the way they are with reference to the behaviour of the particular species, and the local environment. Some will already have had modifications fitted in them to improve selectivity. This will be discussed while the trawl is in the tank.

Gears to be used:

Beam Trawls    Sole trawls Nephrops trawls  Scraper Trawls 
Hard ground trawls Pelagic Trawls Pair Seine nets Pair Trawl Nets
Twin Rig Triple Rig Quad Rigs

Semi Pelagic Rigs

Gill Nets Trammel Nets


Selective devices to be demonstrated - Each will be explained in relation to what fishery it is used in, its main purpose, how efficient it is (reference will be made to results of scientific trials).  There will be discussion to cover fitting of the device into a trawl, handling on board the vessel, economics of using the device and how it fits into legislation.

  • Beam trawls.  - Gear used as part of roller ball project and project 50%
  • Square mesh panels. - Examples that are in current legislation and various others that have been trialled in UK waters
  • Coverless, low headline trawls. - Demonstration of coverless prawn trawl compared to a standard prawn trawl.
  • Large mesh top panels - demonstration of various versions of large mesh fitted in trawls.
  • Various rigid grids in nephrops and shrimp trawls
  • Separator panels and inclined separator panels
  • Various forms of inclined panels. (including Gamrie Bay flip flap and Faithlie cod excluder)
  • T 90 netting and codends.
  • 4 panel codends. (Seltra style codends)
  • Square mesh codends
  • Flying door rig.

4b - Demonstration of selectivity and discard reduction devices that have not already been covered.

It may be possible to include other devices if there are specific requests. (Mike Montgomerie)

The course is free for participants to attend but they will have to fund their own travel and accommodation.