Russa Taign 0408H
Cruise summary report
|Ship name (ship code)||Russa Taign (74RT)|
|Cruise period||2008-05-19 — 2008-06-01|
|Port of departure||Peterhead, United Kingdom|
|Port of return||Peterhead, United Kingdom|
1. To develop procedures for twin trawling the GOV with the vessel's own commercial whitefish trawl.
2. To collect twin trawl samples on selected tows from the IBTS surveys and from the skippers own recommended clear tows.
The scientific team joined Russa Taign in Peterhead at 1000 on 19 May. The remainder of the day was spent rigging the two nets in the twin trawl configuration. The vessel sailed at 0700 to commence trials with the rig off Peterhead. These continued until midday when skipper and SIC were content the gear was fishing well. Sampling tows were then started at 1200. Sample tows were carried out for 30 minutes at approximately 3.5 knots, using both gears. This pattern was continued throughout the cruise. In general, a site was chosen for each days work based on clear tow data from the IBTS or the vessel's plotter. Locations were off Peterhead, Buchan Deeps, Fair Isle, Scalloway Deeps, west of Shetland and Copensay. All catches were worked up separately for the two nets. Target species were cod, haddock, whiting, plaice, lemon sole, saithe, hake, and anglers. The full catch of these species were measured and LF established. The nets were monitored with Scanmar for height, wingspread and water speed/symmetry. The catch was also landed in Scalloway on the evening of the 27 May.
Operations were completed at 1400 on the 31 May. The vessel then steamed to Peterhead arriving at approximately 0100 on the 1 June. Gear was offloaded on the morning of the 1st June, with staff leaving Peterhead around 1200.
70 sampling tows were carried out during the survey, of which 4 were foul. A map was produced showing the tow positions.
Results have not been fully analysed, however, good catches were obtained for cod, haddock, whiting, plaice and lemon sole. Preliminary indications are that the two nets took similar weights of cod, haddock and lemon soles, while the commercial net had higher catches (approximately 2:1 ratio) for whiting and plaice. Good relationships between the catch bulk in the two nets were obtained for haddock, plaice and lemon sole (R2 over 60%). Whiting showed a weak relationship, and there was no relationship for cod. It should be emphasised that these results are very preliminary, and based only on the catch weights.
The data will be analysed in depth at FRS and at present, no clear conclusions can be drawn.
Full results will be prepared for FRS reports and publication.
|Chief scientist||David G Reid (Fisheries Research Services Aberdeen Marine Laboratory)|
|Cruise report||(0.04 MB)|
|Track charts||(00 MB)|