|Ship name (ship code)||Caspian (7401)|
|Cruise period||2008-06-27 — 2008-07-06|
|Port of departure||Macduff, United Kingdom|
|Port of return||Peterhead, United Kingdom|
1. To assess the performance of large mesh netting panels inserted into belly sheet and lower wings of a commercial whitefish trawl in reducing cod by-catches.
2. To carry out underwater observation of the rigging of the large mesh panels and observe cod behaviour when encountering them using self-recording CCD cameras.
Staff and equipment will join Caspian (BF38) at MacDuff on 27 June 2008. Staff will then commence rigging the large mesh panel into one of the vessels whitefish twin trawls. The other trawl will be left unmodified to allow a comparison to be made against the test net.
Initially the test net will be modified by inserting an 800mm diamond mesh panel into the first 160mm diamond mesh belly section. The dimensions of the panel will be approximately 32 meshes across by 5 meshes deep and positioned between the two existing tearing strips. The joining ration between the 160mm and 800mm netting will be 5:1. Depending on results, further panel positions will be assessed such as in the second belly panel and lower wings. If the optimum panel positions are established then the 800mm diamond mesh will be replaced by 400mm diamond mesh netting. During the trials, CCD cameras will be suitably positioned to allow observations to be made on the rigging of the large mesh panel configurations and the behaviour of cod when encountering them.
Throughout the trials, the twin trawl method will be used to assess the performance of the large mesh panels. Selectivity will be measured for cod, anglerfish and megrim but other species will be sampled as available. Both nets will be fished with 70mm codends with the standard net sampling the population on the grounds and the other net with the different large mesh panel configurations.
After initial rigging has been completed, the intention is for the vessel to sail to commercial fishing grounds around the Shetland Isles. Fishing will commence during 28 June and continue until 5 July with ship's accommodation used throughout the charter trials. The cruise will end at Peterhead on 6 July when staff and equipment will return to Aberdeen. Normal contacts will be maintained with the Laboratory.
|Chief scientist||Robert J Kynoch (Fisheries Research Services Aberdeen Marine Laboratory)|
|Specific||Fishing grounds around the Shetland Isles|