Bundesforschungsanstalt für Fischerei
Institut für Seefischerei
Palmaille 9, 22767 Hamburg D Tel. 38905 179 D Fax 38905 263 D 15.9.2005 D Az.: Dr.Ehr./
WH290bre.doc
„WALTHER HERWIG III"
Cruise 290
REPORT 17.07. – 15.08.2006
Personnel
Name Institution
1. Dr. Siegfried Ehrich ISH-BFA (1. leg) 2. Dr. Rudolf Kafemann ISH-BFA 3. Dipl. Biol. Christoph Bucher ISH-BFA 4. Herr Dirk Tinnemeyer ISH-BFA 5. Herr Sascha Bednarz ISH-BFA 6. Herr Hermann Neumann ISH-BFA 7. Herr Piet Linde ISH-BFA 8. Herr Claus Scholz ISH-BFA
9. Dr. Ingrid Kröncke Forsch. Senckenberg 10. Dipl. Biol. A. Markert Forsch. Senckenberg 11. Herr Daniel Bode FTZ Westküste 12. Herr Moritz Mercker FTZ Westküste (1. leg) 13. Frau Henriette Dries FTZ Westküste (2. leg) Objectives
1. To participate in the ICES co-ordinated 'International Bottom Trawl Survey' in the North Sea, 3. quarter 2. Biological monitoring of the fish fauna in 6 small areas (boxes)
3. Distribution of temperature, salinity and nutrients in the area of investigation 4. Monitoring of the benthic epifauna in the boxes and in the German Bight 5. Monitoring of seabirds
6. Comparison fishing with FRV “Scotia”
Narrative (Fig. 1)
W. Herwig III left Bremerhaven the 17th of July 2006. The scientific programme started next morning at ICES-rectangle 38F7. During this day another 3 rectangles were monitored by taking samples of fish, water (nutrients, temperature, salinity) and benthic epi-fauna (Tab. 1). The vessel than worked in the boxes C, L and M (3 days each). The first 2 days of the 4 days in box D a comparison fishing experiment was carried out together with the Scottish FRV “Scotia”. After a two days break in Aberdeen (Scotland) the standard
programme was continued at box B. After two days fishing in 8 ICES-rectangles in the German Bight, 3 days in Box A and another 11 rectangles the scientific program ended the 13th of August. The next day was used to check the fishery winches. The 'W. Herwig III' docked at Bremerhaven the 15th of August.
Tab. 1: Activities (stations) during the cruise
area
GOV-
hauls CTD nutrients 2m-beamtrawl v.Veen grab
Box A 21 15 4 9 9
Box B 20 14 6 9 9
Box C 21 15 9 9 9
Box D 24 18 5 12 12
Box L 21 15 6 9 9
Box M 20 15 6 9 9
ICES-rectangles 23 23 23 23 23
total 150 115 59 80 80
Results (Tab. 1 and Figs. 2-7)
A total of 150 half an hour and valid hauls were made using the GOV trawl equipped with the standard ground gear, of which 127 hauls were carried out in the boxes to monitor changes in species compositions and 23 hauls in different ICES-rectangles as part of the IBTS Q3 survey, mainly within the German Bight.
At 115 stations salinity, temperature and at 59 stations nutrients were measured. Epibenthos was sampled by a 2m beam-trawl at 80 stations and 80 grab samples were taken to investigate the sediment.
The preliminary number at age data for the recruiting year-classes of the commercial important species and the catch data were submitted to the co-ordinator of the IBTS-Q3 survey and ICES resp. to make these data available to the ICES assessment working groups within due time.
Fig. 1 shows the area of investigation. The mean species compositions in the 6 boxes and the variability within the time periods are shown in Figs.2 to 7.
Dr. S. Ehrich; Dr. R. Kafemann
a re a s :
5 2E 5E 6E 7E 8E 9F 0F 1 F 2F 3 F 4F 5 F 6F 7 F 8F 9 G 06 2 °
4 4
5 9
3 6 4 8
4 0
3 2 5 0
4 2 5 7
3 4 5 3
4 6
3 8 5 5
3 0 2 9
5 1
5 0 ° 5 1
4 3
5 8
3 5 4 7
3 9
3 1 4 9
6 1
4 1 5 6
3 3
5 2 4 5
6 0
3 7
5 4
5 ° W4 3 2 1 0 1 2 3 4 5 6 7 8 9 1 0 1 1 ° E
D
L M
B
C
A
Fig. 1: „Walther Herwig III“. Cruise no. 290. Area of investigation and boxes
0 200 400 600 800 1000 1200 1400 1600 1800 2000
1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
year
mean catch rate (kg/30min)
others sprat scad mackerel herring whiting cod plaice dab
Box A
Fig. 2: Box A: German Bight: Main species composition (kg/30min) from 1987 to 2006 (summer)
0 200 400 600 800 1000 1200 1400 1600 1800 2000
1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
year
mean catch rate (kg/30min)
others sprat mackerel herring whiting haddock cod dab
Box B
Fig. 3: Box B. English coast. Main species composition (kg/30min)
from 1987 to 2006 (summer)
0 50 100 150 200 250 300 350 400 450
1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
year
mean catch rate (kg/30min)
others herring whiting haddock cod dab
Box C
Fig. 4: Box C. Danish coast. Main species composition (kg/30min) from 1986 to 2006 (summer)
0 500 1000 1500 2000 2500 3000 3500
1986 1987
1988 1989
1990 1991
1992 1993
1994 1995
1996 1997
1998 1999
2001 2002
2003 2004
2005 2006 Jahr
mittlerer Fang (kg/30min)
andere Makrele Hering Stintdorsch Wittling Schellfisch Kabeljau Limande Kliesche
Box D
Fig. 5: Box D. Scottish coast. Main species composition (kg/30min)
from 1986 to 2006 (summer)
0 200 400 600 800 1000 1200 1400 1600 1800 2000
1999 2001 2002 2003 2004 2005 2006
Jahr
mittlerer Fang (kg/30min)
andere Hering Makrele Seelachs Wittling Schellfisch
Box L
Fig. 6: Box L. Norwegian coast. Main species composition (kg/30min) in 1999 and from 2001 to 2006 (summer)
0 200 400 600 800 1000 1200 1400
1999 2001 2002 2003 2004 2005 2006
Jahr
mittlerer Fang (kg/30min)
andere Stintdorsch Hering Makrele Seelachs Wittling Schellfisch Kabeljau
Box M
