Institut für Seefischerei

(1)

Institut für Seefischerei

Palmaille 9, 22767 Hamburg Telefon 040 38905-108 Telefax 040 38905-263 09.09.2011 Az.: Pa../v.S./3305

„SOLEA“

Cruise 644 REPORT 16.08. – 01.09.2011

Personnel

Name Institution

Kay Panten SF

Thomas Kehlert SF

Christine Petersen-Frey SF

Christian Braun SF

Theresa Conradi SF

Birger Kreutz Multimar

Objectives

1. To participate in the ICES co-ordinated “International Beam Trawl Survey” in the North Sea 2. Biological monitoring of the fish fauna in proposed FFH protected areas in the German Bight 3. Distribution of temperature and salinity in the area of investigation

Narrative (Fig. 1)

The port of Cuxhaven was left on 16.8., steaming over night with good weather conditions to the area scheduled for the Beam Trawl Survey west of Sylt, north of the Danish border (ca. 55°N). On the fourth day of the survey priority was given to monitoring the FFH area “Dogger Tail End”. The following days the offshore stations were sampled with different courses depend on wind direction and wind force. On August 26 the BTS was finished and a gale-force wind forced the stay in Esbjerg Harbour for four days. With this opportunity the representative of multimar left the ship with the up to now attained aquarium stock. Back at sea the FFH monitoring was continued at “Sylter Außenriff”. Due to loss of time “Borkum Riffgrund” can’t carried out this year. The cruise ended in Cuxhaven in the evening on 31.8.

(2)

Results (Fig. 2 – 7)

A total of 55 half an hour and valid hauls were made using the 7m beam trawl. Additional 22 15min hauls were carried out in the FFH areas. At 61 stations salinity and temperature were measured.

The species composition distribution showed the usual geographic pattern with dab as the most frequent fish, followed by plaice and grey gurnad.

Toward the north and the west soon the importance of long rough dab and starry ray in the biomass increases. Still, in the survey area some larger (up to 50 cm) plaice can be found, although quite sporadically.

Also in the FFH areas, nothing unusual was caught. In the Sylt area the common starfish (Asterias rubens) dominates with more than 80% in the catch composition.

Dipl.-Biol. K. Panten

(3)

2°E 3°E 4°E 5°E 6°E 7°E 8°E 9°E

53°N

53.5°N 54°N 54.5°N 55°N 55.5°N 56°N 56.5°N 57°N 57.5°N

58°N F2 F3 F4 F5 F6 F7 F8

44

43

42

41

40

39

38

37

36

35

Dogger Tail End

Sylter Aussenriff

Borkum Riffgrund

1 3 2 4 6 5 7 8

10 9 11 12 13 1514 1716 18

19 20 212223

24 25

26 27

28 29 30 31

32

33 35 34

36 37

3938 40 41 42 43

44 45

46 47

48 49

50 5251

53 54 55 57 55

58 59

60 61

62 63 64 65 66 67

6968 7170 7273 74757677

Fig. 1: “Solea“, Cruise no. 644 , Haul positions and area of investigation

(4)

Catch composition and length distribution during Beam Trawl Survey

MERLUCCIUS MERLUCCIUS

0.50%

MICROSTOMUS KITT 1.76%

HIPPOGLOSSOIDES PLATESSOIDES

1.89%

RAJA RADIATA 2.57%

Invertebrates 35.01%

SPATANGUS PURPUREUS 1.58%

NEPTUNEA ANTIQUA 1.43%

ECHINOCARDIUM 1.38%

APHRODITA ACULEATA 1.62%

ASTERIAS RUBENS 2.16%

BUCCINUM UNDATUM

2.63%

PAGURIDAE 2.91%

LUIDIA SARSI 3.20%

ASTROPECTEN IRREGULARIS

4.56%

LIMANDA LIMANDA 13.19%

PLEURONECTES PLATESSA

14.41%

EUTRIGLA GURNARDUS

29.00%

PORIFERA 4.63%

other Fish 1.67%

ECHINUS 1.17%

other Invertebrates 7.74%

BUGLOSSIDIUM LUTEUM

0.65%

PSETTA MAXIMA 0.48%

RAJA RADIATA 0.42%

EUTRIGLA GURNARDUS 0.94%

other Fish 3.23%

15.69%

ECHINOCARDIUM 2.15%

PAGURIDAE 2.17%

MACROPIPUS HOLSATUS

5.96%

6.41%

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

0 30 60 90 120 150

0 5 10 15 20 25 30 35 40

Length class [cm]

rel. Frequency [%]

0 30 60 90 120 150

0 5 10 15 20 25 30 35 40

Length class [cm]

rel. Frequency [%]

Fig. 4: Length distribution of Dab in 39-43F4&5 Fig. 5: Length distribution of Dab in 39-43F6&7

0 30 60 90 120 150

0 5 10 15 20 25 30 35 40 45 50

Length Class [cm]

rel. Frequency [%]

0 30 60 90 120 150

0 5 10 15 20 25 30 35 40 45 50

Length class [cm ]

rel. Frequncy [%]

Fig. 6: Length distribution of Plaice in 39-43F4&5 Fig. 7: Length distribution of Plaice in 39-43 F6&7

(5)

Catch composition and length distribution during FFH Monitoring

35.14%

Invertebrata 18.17%

BUCCINUM UNDATUM

0.91%

NEPTUNEA ANTIQUA 0.49%

PORIFERA 0.62%

1.63%

PAGURIDAE 4.31%

5.92%

other Fish 4.54%

4.84%

MICROSTOMUS KITT 7.16%

Fig. 8: Catch composition in FFH-Area „Dogger Tail End“

5.34%

PAGURIDAE 1.69%

0.35%

0.49%

POMATOSCHISTUS MINUTUS

0.30%

other Fish 0.71%

Fig. 9: Catch composition in FFH-Area „Sylter Aussenriff“