R1/12
Not to be cited without prior reference to the Marine Laboratory, Aberdeen FRV Scotia
Cruise 1008S REPORT
5 – 29 August 2008 Personnel
K A Coull (SIC) C G Davis
I Penny K Summerbell L Ritchie
E Guiry (5–16 August) H Drewery (16–29 August)
R Eades (JNCC)
A Batty (JNCC)
Objectives
1. To undertake an internationally co-ordinated demersal trawling survey of the North Sea.
2. Obtain temperature and salinity profiles at each trawling station.
3. Obtain low nutrient water seawater samples from statistical rectangle 45F1 (or an adjacent rectangle.
Out-turn days per project: 25 days – RV0809 Narrative
Due to the vessel having to undergo repair between voyages, sailing was delayed until 5 August. The vessel sailed from Aberdeen at 1500 and completed one haul at the trawling station off Aberdeen. A further 4 stations were successfully completed off the east coast of Scotland the following day and with the extended weather forecast indicating favourable weather, the decision was taken to work on the northern part of the survey area first. The vessel then proceeded in a northerly direction, covering stations off the northeast coast, Moray Firth, Orkney and southeast Shetland regions. With continuing good weather, the stations west of the Shetland Isles were completed on 12 August. Scotia then worked easterly, entering Norwegian waters on the evening of 13 August. A further 3 stations were completed in this area before docking in Stavanger for the mid cruise break on the morning of 15 August. Scotia departed from Stavanger at 0900 on 16 August and completed 2 stations in the Norwegian Sector before returning to complete a series of stations around the Fladen area. Scotia then completed the southern stations within the Norwegian Sector on 20 August, with the stations in the Danish sector being completed on the morning of 22 August. The southern stations in the Dutch and German territorial waters were
the evening of 27 August, 3 additional stations off the east coast of Scotland were completed in support of the international coverage.
Scotia then returned to Aberdeen at 2330 on 28 August, with unloading taking place during 29 August.
Results
The survey was successfully completed with the standard 87 stations being sampled and an additional two stations in statistical rectangles 40E8 and 41E7 being completed to support the international coverage. All catch data was processed at sea and on returning to Aberdeen, all otoliths were read and results processed within the sea-going suite of software programmes.
The charts shown below give an indication of the survey indices for juvenile (0+) cod, haddock, whiting and Norway pout for the period 1990 – 2008.
Number 0+ cod per 10 hours
0 20 40 60 80 100 120 140 160
1990 1992 1994 1996 1998 2000 2002 2004 2006 2008
Number 0+haddock per 10 hours
0 10000 20000 30000 40000 50000 60000
1990 199
2 1994
1996 199
8 2000
2002 2004
2006 2008
no per 10 hours
Number 0+whiting per 10 hours
0 5000 10000 15000 20000 25000
1990 1992
1994 1996
1998 2000
2002 2004
2006 2008
Number 0+Norway pout per 10 hours
0 10000 20000 30000 40000 50000 60000
1990 1992
1994 1996
1998 2000
2002 2004
2006 2008
Numbers of juvenile cod (0+) were down on last year’s numbers and more in line with the long term trend. Distribution of juvenile cod (Figure 1) was restricted to inshore stations off the Scottish coast. Numbers of juvenile haddock showed an increase on the last year but with the exception of the 2005 year class, the survey indices for this species in recent years
Length, weight, sex and maturity data were collected from several species, as defined by WGIBTS. Frozen samples of fish were also collected in order to fulfil requests received from several sources, including:
• Sea Mammal Research Unit;
• Food Standards Agency;
• Aberdeen University.
The ship’s thermosalinograph was run continuously throughout the cruise and a CTD and reverser bottle were deployed at each station to obtain temperature and salinity profiles.
Samples of low nutrient sea water were collected in the region of statistical rectangle 45F1.
The Scanmar system was used at each station to monitor headline height, wing spread, door spread and distance covered by the fishing gear.
K A Coull 7 October 2008
Seen in draft: Captain Eric Casson
4 2 0 2 4 6 8 53N
54N 55N 56N 57N 58N 59N 60N 61N 62N
0
2 0
0 0
0 0
0 0
0 0
0 0
0 72 4
0 0
0 0
0 0
0 0
0 0 0 0 0
0 0 0 0 0
0 0 0
0 0 0 0 0 0
0 0
0 0 0
0 0
0 0 0
0 0
0 0
0 0 0 0
0 0
0 0 0
0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0
0 0
0 0 0 0
0 6
Quarter 3 - Groundfish Survey 2008
52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
Distribution of Juvenile (0+) cod (number per hour)
Figure 2
4 2 0 2 4 6 8
53N 54N 55N 56N 57N 58N 59N 60N 61N 62N
4 4620 0
610 362
42 0
32 0
44 2 12 306
6 1144 192
12 0
4 0
0 0
0 92
0 2 0 0 0
0 0 6 9 70
30 16 28
50 30 36 14 18 26
230 134
178 2 30
0 2
2 0 0
0 0
10 2
0 24 0 2
0 0
0 0 0
0 0 0
8 0 0 0 0 0 0 0 4 4
0 0 0
0 0
0 0 82 12
270 4964
Quarter 3 - Groundfish Survey 2008
52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
Distribution of Juvenile (0+) Haddock (number per hour)
4 2 0 2 4 6 8 53N
54N 55N 56N 57N 58N 59N 60N 61N 62N
2152 19786 8
10 26
80 4
318 0
16 0 3588 8 1306 34416 4224
2 0
740 8
6 0
20 100 18 0 2 0 0
0 0 0 153 38
352 24 38
0 8 304 2234 2774 1762
1130 2590
238 0 2
48 22
8 36 14
0 2
418 36
10 418 0 2
2 8
636 3214 84
1112 3116 142
176 14 0 0 22 0 2 0 14 72
0 4 4
0 86
26 6 0 4
114 9390
Quarter 3 - Groundfish Survey 2008
52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
Distribution of Juvenile (0+) Whiting (number per hour)
Figure 4
4 2 0 2 4 6 8
53N 54N 55N 56N 57N 58N 59N 60N 61N 62N
2818 47982 0
0 6
0 0
0 24
0 0 1696 21290
788 68764 7394
0 28
2482 15488
976 200
384 0
1558 61772
298 0 0
1724 48 0 0 0
0 0 458
8734 926 0 0 0 226
22 46
0 318 0
18 0
0 0 0
0 0
0 0
0 0 0 0
0 0
0 0 0
0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0
0 0
0 0 14450 0
8740 37016
Quarter 3 - Groundfish Survey 2008
52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
Distribution of Juvenile (0+) Norway pout (number per hour)
53N 54N 55N 56N 57N 58N 59N 60N 61N 62N
Quarter 3 - Groundfish Survey 2008
52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
05/08
28/08
