Presentation of the mackerel- ecosystem survey (IESSNS)
2. July – 12. August 2014
Leif Nøttestad
Principal scientist (PhD)
Materials and methods
• Vessels: M/V ”Brennholm” M/V ”Vendla”, M/V ”Finnur Fridi”
og R/V ”Arni Fridriksson”
• Survey period: 2 July – 12 August 2014
• Area coverage: 2.45 millioner km2
• 58°N - 77°N og 26°E - 42°W
• Standarized 30 min pelagic trawling with Multpelt 832
• Multi-frequency echosounder and multibeam sonars
• Plankton sampling WP2 net 0-200 m depth
• CTD measurements 0-500 m depth
• Underwater video cameras inside the trawl
• ADCP, light measurements and weather observations
• Whale observations
Trawl stations during the IESSNS survey 2014
Makcerel catch rates (kg)
Mackerel distribution (kg/km2)
Age-disaggregated internal consistancy plot
Consistancy plot for each
year class
Mackerel average weight (g)
Average length (cm) for NEA mackerel
60°
65°
70°
75°
55° 40° 30° 20° 10° 0° 10° 20° 30°
Mackerel July 2014
34
37
39 38
39 34
38
Age and length distribution of mackerel
Acoustic density for NSS herring within the area covered
60°
65°
70°
75°
55° 40° 30° 20° 10° 0° 10° 20° 30°
Herring July 2014
Average lenght distribution NSS herring
60°
65°
70°
75°
55° 40° 30° 20° 10° 0° 10° 20° 30°
Herring July 2014
34 32
26
Length and age distribution NSS herring
Distribution and overlap of mackerel and herring
Temperature at 10 m depth
60°
65°
70°
75°
55° 40° 30° 20° 10° 0° 10° 20° 30°
Temperature 0m July-aug. 2014
10
Temperature at 20 m depth
60°
65°
70°
75°
55° 40° 30° 20° 10° 0° 10° 20° 30°
Temperature 20m July-aug. 2014
10
5
12
Temperature at 50 m depth
60°
65°
70°
75°
55° 40° 30° 20° 10° 0° 10° 20° 30°
Temperature 50m July-aug. 2014
6
5
10
7
Temperature at 200 m depth
60°
65°
70°
75°
55° 40° 30° 20° 10° 0° 10° 20° 30°
Temperature 200m July-aug. 2014
5
4
9
7
Surface temperature anomaly July 2014
Surface temperature anomaly July 2013
Plankton distribution and concentrations
60°
65°
70°
75°
55° 40° 30° 20° 10° 0° 10° 20° 30°
plankton
July-August 2014
5
10 5
15
Marine mammal observations
