Federal Research Institute for Rural Areas, Forestry and Fisheries

Thünen-Institute of Sea Fisheries

Palmaille 9, 22767 Hamburg Telephone +4940 38905-108 Telefax +4940 38905-263 09.10.2017 Az.: Pa./vS/4197

„SOLEA“ Cruise 738 REPORT 18.08. – 04.09.2017

Personnel

Name Institution

Kay Panten SF Colin Buster-Mensah SF David Hofmann SF Thomas Kehlert SF Karin Krüger SF Dimitri Schuschkow SF

Objectives

1. Participation in the ICES co-ordinated “International Beam Trawl Survey” in the North Sea 2. Determination of temperature and salinity in the area of investigation

Narrative (Fig. 1)

FRV “Solea” left the port of Cuxhaven in the afternoon on 18th August. Working started the next day by sampling the ICES statistical rectangle 39F7. Due to strong wind, the fishing had to be stopped from noon until the next evening. On the following four days nine rectangles could be processed in the south-western part of the study area. A technical defect forced on 25th August a repair stay in the port of Esbjerg. From 26th to 29th August further 10 rectangles were processed. Then a second repair stay in Esbjerg was necessary. The remaining four rectangles between Jammerbucht and Limfjord were fished from 31st August until 2nd September. The work in the FFH area "Sylter Außenriff" was carried out on 3rd September. Due to a medical emergency in the family of a member of the scientific

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crew, the trip was already finished on the morning of 04th September in Cuxhaven. The return trip to Hamburg took place the same day.

Results (Fig. 2 – 8)

A total of 71 valid hauls with a standard duration of 30 minutes were conducted with the 7m beam trawl. At 66 stations salinity and temperature were measured. The distribution of composition shows the usual geographic pattern with dab as the most frequent fish species, followed by plaice, grey gurnard and lemon sole. Towards the North of the investigation area the importance of dab in the biomass decreases. Here, plaice is only occurring sporadically with some larger (up to 50 cm) individuals.

Dipl.-Biol. K. Panten

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F3 F4 F5 F6 F7 F8 F9 58°N

44

57.5°N 4950 51 52

30 55 53 43 29 32 54 31 60 33 34 36 59 56 35 57°N 58 57 28 61 37 25 62 27 38 42 26 39 63 56.5°N 40

43 42 41 17 18 19 41 44 16 45 20 56°N 46 47 14 21 48 15 23 13 40 22 24

55.5°N 12 5 9 11 6 10 4 3 39 7 8 2 1 55°N 6766 64 68 65 69 7071 38

54.5°N

37

54°N

36

53.5°N

35

53°N 3°E 4°E 5°E 6°E 7°E 8°E 9°E

10°E 10°E

Fig. 1: “Solea“, Cruise no. 738, Haul positions and area of investigation

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Catch composition in kg and length distribution during Beam Trawl Survey

Merlangius Solea solea; 26.8 merlangus; 17.6 Neptunea antiqua; Eutrigla gurnardus; Asterias rubens; Hippoglossoides Callionymus lyra; 25.9 platessoides; 19.7 183.9 31.6 510.6 other Fish; 57.9 other Fish; 90.1 Amblyraja radiata; Pagurus bernhardus; Buglossidium luteum; Pagurus bernhardus; 58.9 169.9 32.8 283.2

Microstomus kitt; Buccinum undatum; Pleuronectes Astropecten 68.3 91.9 platessa; irregularis; 263.5 1007.0 Porifera; 77.9 ; 159.3 Limanda limanda; Invertebrates; Luidia sarsii; 75.7 261.0 1015.1 Liocarcinus Asterias rubens; 73.7 Invertebrates; depurator; 88.0 1563.9 Brissopsis lyrifera; Liocarcinus holsatus; 61.3 68.1 Astropecten Luidia sarsii; 25.4 Pleuronectes irregularis; 53.2 platessa; 319.3 Arctica islandica; 17.4 Spatangus Alcyonium digitatum; purpureus; 33.0 Limanda limanda; 1138.6 17.1 Colus gracilis; 30.3 Colus gracilis; 16.3

other Invertebrates; other Invertebrates; 164.2 115.0

Fig. 2: Catch composition in 39-43F4&5 Fig. 3: Catch composition in 39-43F6&7, 43F8&9 (offshore) (inshore)

140 140

120 120

100 100

80 80

60 60 rel.[‰] Frequency rel.[‰] Frequency

40 40

20 20

0 0 5 10 15 20 25 30 35 40 5 10 15 20 25 30 35 40

Length class [cm] Length class [cm] Fig. 4: Length distribution of Dab in 39-43F4&5 Fig. 5: Length distribution of Dab in 39-43F6&7, 43F8&9

80 160

70 140

60 120

50 100

40 80 rel. [‰] Frequency rel.[‰] Frequency 30 60

20 40

10 20

0 0 5 10 15 20 25 30 35 40 45 50 55 60 65 5 10 15 20 25 30 35 40 45 50 55 60 65 Length class [cm] Length class [cm] Fig. 6: Length distribution of Plaice in 39-43F4&5 Fig. 7: Length distribution of Plaice in 39-43 F6&7, 43F8&9

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Catch composition and length distribution during FFH Monitoring

Asterias rubens; other Fish; 14.6 295.9

Arnoglossus Liocarcinus holsatus; laterna; 4.4 133.8 Callionymus Pagurus bernhardus; lyra; 4.6 68.8 Agonus cataphractus; 5.3 Astropecten irregularis; 14.6 Buglossidium Invertebrates; luteum; 8.9 541.9 Liocarcinus depurator; 6.9 Pleuronectes platessa; 30.4 Cancer pagurus; 6.9

Spisula solida; 6.6 Limanda limanda; ; 1.9 38.8 lutraria; 1.5

Carcinus maenas; 1.3

other Invertebrates; 3.6

Fig. 8: Catch composition in FFH-Area „Sylter Aussenriff“