Cruise inventory

RV Lough Foyle LF/18/92

Cruise summary report

Cruise Info. 
Ship name (ship code)RV Lough Foyle (74LG)
Cruise identifierLF/18/92
Cruise period1992-07-19 — 1992-07-31
StatusCompleted
Port of departureBelfast, United Kingdom
Port of returnBelfast, United Kingdom
PurposeFisheries
ObjectivesPelagic fish acoustic survey
1. To estimate the biomass and age-compostion of the mixed Manx and Mourne stocks of herring in the northern Irish Sea.
2. To dertermine the distribution and biomass of sprat.
3. To further improve acoustic survey methods on Lough Foyle.
Chief scientistMike Armstrong (Department of Agriculture for Northern Ireland)
Cruise reportRV Lough Foyle LF/18/92 cruise report lf18_92.pdf — access key 'C' (0.24 MB) 
Ocean/sea areas 
GeneralIrish Sea and St. George's Channel
SpecificNorth Irish Sea
Track chartsRV Lough Foyle LF/18/92 cruise track — lf18_92track.pdf (00 MB) 
Measurements 
Biology and fisheries 
ZooplanktonQuantity: number of measurements = 2
Description: Near the Targets on tow 23 adult and young herring were caught. On tow 24 a catch of sprats and jellyfish. The transducers were successfully calibrated.
Pelagic fishQuantity: number of measurements = 4
Description: 4 trawl samples tows 1-4 were taken during the day.
Pelagic fishQuantity: number of measurements = 1
Description: Tow 25 was to fish a mixture of herring and sprat.
Pelagic fishQuantity: number of measurements = 2
Description: Near the Targets on tow 23 adult and young herring were caught. On tow 24 a catch of sprats and jellyfish. The transducers were successfully calibrated.
Pelagic fishQuantity: number of measurements = 4
Description: Tows 19-22 were completed mainly containing sprats and herring. Tow 22 was unsucessful as the target was probably plankton.
Pelagic fishQuantity: number of measurements = 4
Description: Tows 15-17 were aimed at catching adult herring. Tow 16 was unsuccessful. Tow 18 was to catch sprats and young herring.
Pelagic fishQuantity: number of measurements = 1
Description: Tow 12 was taken, the haul being sprats again. The echosounder was also calibrated.
Pelagic fishQuantity: number of measurements = 3
Description: Tows 9, 10 and 11 contained mainly spats again.
Pelagic fishQuantity: number of measurements = 4
Description: Tows 5-8 were taken from Dundalk Bay to Lambay Island, trawl consisted mainly of sprats.
Demersal fishQuantity: number of measurements = 3
Description: Tows 9, 10 and 11 contained mainly spats again.
Demersal fishQuantity: number of measurements = 4
Description: Tows 15-17 were aimed at catching adult herring. Tow 16 was unsuccessful. Tow 18 was to catch sprats and young herring.
Demersal fishQuantity: number of measurements = 1
Description: Transects were surveyed and it was noted that concentrations of herring were found at the Targets.
Demersal fishQuantity: number of measurements = 1
Description: A grid of transect was surveyed between the Calf of Man and Douglas. Herring targets were found to have risen from the seabed after dark and were fairly abundant.
Demersal fishQuantity: number of measurements = 1
Description: Tow 25 was to fish a mixture of herring and sprat.
Demersal fishQuantity: number of measurements = 3
Description: They followed transect 26, deviating to investigate the ''herring peaks'' before finally reaching transect 30.
Demersal fishQuantity: number of measurements = 4
Description: Tows 19-22 were completed mainly containing sprats and herring. Tow 22 was unsucessful as the target was probably plankton.
Demersal fishQuantity: number of measurements = 4
Description: Tows 5-8 were taken from Dundalk Bay to Lambay Island, trawl consisted mainly of sprats.
Demersal fishQuantity: number of measurements = 2
Description: Near the Targets on tow 23 adult and young herring were caught. On tow 24 a catch of sprats and jellyfish. The transducers were successfully calibrated.
Demersal fishQuantity: number of measurements = 4
Description: 4 trawl samples tows 1-4 were taken during the day.
Acoustic reflection on marine organisms.Quantity: activity duration in days = 10
Description: Acoustic surveys. 25 midwater trawls also completed