This work was carried out as part of the Fisheries Science Partnership (FSP)
programme. The primary objective of the project was to obtain data on the
differences between the currently permitted and proposed new trawl
configurations, principally to move from the widespread use of 80mm mesh cod
end to a default of 100mm. This information will help to provide evidence on
the performance of more selective trawl configurations to inform on proposed
changes to technical measures regulations in the southwest otter trawl mixed
fishery.
For this purpose, two trials lasting 6 days each took place in ICES Division
7e on the twin-rig otter trawler Rockfisher (SU6) in the months of October to
December 2020. The vessel conducted simultaneous comparative tows of the
control gear and two experimental gears. The first trial compared two trawls,
both with 100mm cod ends, and one with an 80mm square mesh panel (SMP) and the
other with 100mm SMP. A total of 19 paired hauls were collected for this
trial. The second trial compared 100mm cod end with an 80mm SMP to an 80mm cod
end with an 80mm SMP (as normally used by the vessel). A total of 14 paired
hauls were completed for the second trial.
At each station sampled, shot and haul, positional, times, depths and towing
speed information were recorded, and for all species of fish length
distribution data were taken, including collecting data on the benthic
component of the catch.
