Cruise inventory

FRV Clupea 0807C

Cruise summary report

Cruise Info. 
Ship name (ship code)FRV Clupea (74CU)
Cruise identifier0807C
Cruise period2007-06-01 — 2007-06-14
StatusCompleted
Port of departureFraserburgh, United Kingdom
Port of returnFraserburgh, United Kingdom
PurposeFisheries
ObjectivesObjectives

The primary objective of this monitoring cruise was to determine the abundance of sandeels on the main sandbank fishing grounds (the Wee Bankie, Marr Bank and Berwick's Bank) within the northwestern North Sea sandeel closure area. The absolute abundance index is derived through combination of a demersal trawl survey index of sandeel abundance in the seabed sediments and an estimate of the abundance of sandeels in the water column determined by acoustic survey. The cruise thus had the following objectives:

1. To carry out an acoustic survey to determine an abundance estimate for sandeels in the in the water column. Three frequencies, 38, 120, and 200 kHz were used to aid species recognition. This acoustic survey also produced herring and sprat abundance estimates. Concentrations of fish were sampled using the pelagic trawl to determine species composition and length frequency distributions. Sub samples of the fish caught were weighed and had otoliths removed to establish length-weight relationships and age composition.

2. To carry out a demersal trawl survey to determine an abundance index for sandeels in the seabed sediment. This demersal trawl survey also produced abundance indices for herring and sprats, the two other main "prey" species, as well as abundance indices for the major piscivorous fish predators in the area, whiting, haddock and cod. At each trawl station, the length frequency of all fish species caught was determined. Sub-samples of sandeels, herring, sprats, cod, haddock, and whiting were weighed to determine length-weight relationships. Otoliths were removed from sandeels and clupeids to determine age composition. Sub-samples of the gadoid predators were retained and frozen for subsequent dietary and age composition analysis if required.

3. Simultaneously with the demersal trawl survey, hydrographic survey was undertaken using a Seabird 19 CTD sampler fitted with a fluorometer to dete
Chief scientistSimon Greenstreet (Fisheries Research Services Aberdeen Marine Laboratory)
ProjectMF07N
Coordinating bodyFRS
Cruise reportFRV Clupea 0807C cruise report 0807c.pdf — access key 'C' (0.15 MB) 
Ocean/sea areas 
GeneralNorth Sea
SpecificNorthwestern North Sea
Measurements 
Physical oceanography 
Surface measurements underway (T,S)Quantity: number of stations = 19
Description: hydrography
Water bottle stationsQuantity: number of stations = 19
Description: water samples for chlorophyll analysis
Subsurface temperature and salinity measurementsQuantity: number of stations = 19
Description: hydrography
Biology and fisheries 
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of stations = 19
Description: water samples for chlorophyll analysis
BirdsQuantity: number of surveys = 4
Description: 5 minute seabird surveys
Mammals and reptilesQuantity: number of specimens = 13
Description: marine mammal sightings: minke whale, bottlenose dolphin, white-beacked dolphine, porpoise and grey seal
Pelagic fishQuantity: number of stations = 4
Description: pelagic trawl
Demersal fishQuantity: number of stations = 19
Description: demersal trawling
Acoustic reflection on marine organisms.Quantity: number of surveys = 3
Description: acoustic surveys
Other biological/fisheries measurementDescription: sandeel and clupeid otolith samples
Geology and geophysics 
Single-beam echosoundingQuantity: number of surveys = 3
Description: acoustic surveys
Data held at BODC 
Series/Profiles 
19  CTD/STD cast
Electrical conductivity of the water column
Chlorophyll pigment concentrations in water bodies
Vertical spatial coordinates
Salinity of the water column
Temperature of the water column
Reference numbers
Electrical conductivity of the water column
Chlorophyll pigment concentrations in water bodies
Vertical spatial coordinates
Salinity of the water column
Temperature of the water column
Reference numbers

BODC idDate/TimeLocationDoc.
9055612007-06-08 06:40 56° 27' 29" N  2° 7' 55" W  View metadata report for BODC series reference number 905561
9055732007-06-10 07:05 56° 27' 8" N  1° 47' 17" W  View metadata report for BODC series reference number 905573
9055852007-06-10 09:10 56° 17' 34" N  1° 49' 36" W  View metadata report for BODC series reference number 905585
9055972007-06-10 11:05 56° 7' 10" N  1° 51' 17" W  View metadata report for BODC series reference number 905597
9056042007-06-10 12:55 56° 2' 28" N  2° 1' 45" W  View metadata report for BODC series reference number 905604
9056162007-06-11 05:55 56° 2' 17" N  1° 39' 41" W  View metadata report for BODC series reference number 905616
9056282007-06-11 08:10 56° 1' 54" N  1° 21' 22" W  View metadata report for BODC series reference number 905628
9056412007-06-11 10:05 56° 7' 0" N  1° 31' 27" W  View metadata report for BODC series reference number 905641
9056532007-06-11 12:20 56° 16' 50" N  1° 31' 44" W  View metadata report for BODC series reference number 905653
9056652007-06-11 13:50 56° 12' 7" N  1° 39' 55" W  View metadata report for BODC series reference number 905665
9056772007-06-12 04:45 56° 7' 10" N  2° 30' 24" W  View metadata report for BODC series reference number 905677
9056892007-06-12 06:35 56° 2' 25" N  2° 19' 32" W  View metadata report for BODC series reference number 905689
9056902007-06-12 08:25 56° 7' 56" N  2° 9' 16" W  View metadata report for BODC series reference number 905690
9057082007-06-12 10:15 56° 12' 7" N  1° 59' 59" W  View metadata report for BODC series reference number 905708
9057212007-06-12 12:20 56° 17' 15" N  2° 11' 25" W  View metadata report for BODC series reference number 905721
9057332007-06-12 14:03 56° 11' 38" N  2° 20' 12" W  View metadata report for BODC series reference number 905733
9057452007-06-13 05:40 56° 21' 46" N  2° 22' 7" W  View metadata report for BODC series reference number 905745
9057572007-06-13 07:45 56° 27' 2" N  2° 30' 39" W  View metadata report for BODC series reference number 905757
9057692007-06-13 10:45 56° 22' 1" N  1° 57' 50" W  View metadata report for BODC series reference number 905769