FRV Scotia 1015S
|Ship name (ship code)||FRV Scotia (748S)|
|Cruise period||2015-07-30 — 2015-08-20|
|Port of departure||Aberdeen, United Kingdom|
|Port of return||Aberdeen, United Kingdom|
1. To complete an internationally coordinated demersal trawling survey in the North Sea in ICES area IV.
2. To obtain temperature and salinity data from the surface and seabed at each trawling station using a SEABIRD 19+ CTD.
3. Collect additional biological data in connection with the EU Data Collection Framework (DCF).
Loading of the trawl gear will provisionally take place on 27 July with rigging and testing being completed on the same day. Loading of the scientific gear will also take place on the same day. Scotia will then sail on the morning of Thursday 30 July. The first station will be Northeast of Peterhead at Buchan Deeps and once the safety drills have been completed Scotia will then proceed to the first station where a shakedown haul will be completed in advance of the first real haul in order to check the net configuration and the Scanmar units. An operational daily survey plan will be formulated by the SIC subsequent to meetings with both the Fishing master and the Captain.
There are 84 programmed rectangles to be surveyed. 10 of these rectangles may be dropped depending on the progress of the other survey participants. It was decided at the Bergen meeting in April 2015 that the IBTSWG would propose a tow duration experiment during the Q3 North Sea survey. For every rectangle within the survey area where two trawls are currently undertaken, one would be of 30 minutes duration whilst the other would be of 15 minutes duration. This will allow a dual set of abundance indices to be calculated for the assessed species, which will be evaluated in time for IBTSWG 2016. As a parameter of diversity, species richness will also be compared. The reduction of stations as well as the tow duration experiment should allow additional stations to be sampled in the area to the south and west of Shetland. Contact will be maintained with the other survey participants prior to and during the survey and a decision will be made regarding these additional stations once the survey is underway. Trawling will be undertaken during the hours of daylight, which will vary depending on the vessels latitude at any given time. The GOV survey trawl will be used during the survey with the short 47m sweeps used throughout the survey area. Two groundgear types will be utilised during the survey, the lighter A rig being used on all the survey stations south of 57'30N and the heavier B rig being utilised on all the stations north of 57'30N. The scanmar system will be used to monitor the headline height, wingspread and door spread for each haul. Bottom contact data from each trawl will also be collected using the NOAA bottom contact sensor, which will be mounted in the centre of the ground-gear. In addition to the routine sampling, biological data will be collected for target species in line with the EU data regulation. All fish will be processed in accordance with Standing Instructions.
CTD casts will be taken at every trawl station. These provide surface and bottom temperature and salinity information. Reverser bottles affixed to the CTD wire will also be used to collect water samples that will be analysed back at the lab and will provide information on salinities, nitrates, silicates and phosphates. In addition, the ships thermosalinograph will be run continuously throughout the survey and will provide sea surface temperature and salinity data.
|Chief scientist||Finlay Burns (Marine Scotland Aberdeen Marine Laboratory)|
|Specific||Northern North Sea|