Cruise inventory

RRS James Clark Ross JR19943001 (JR06 Leg 2)

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS James Clark Ross (74JC)
Cruise identifierJR19943001 (JR06 Leg 2)
Cruise period1994-02-01 — 1994-03-03
StatusCompleted
Port of departureGrytviken, South Georgia and the South Sandwich Islands
Port of returnStanley, Falkland Islands (Malvinas)
PurposeResearch
ObjectivesUndertake large scale oceanographic/hydroacoustic transects in the Scotia Sea using underway monitoring and CTD casts, with reference to remote sensed data, to investigate large and mesoscale variability. To undertake a study of predator/prey interactions between the major bird and seal populations based in South Georgia and their food in the ocean nearby. Devoted to squid and fish consumers. Twin-ship work to study meso- and fine-scale distribution of krill swarms with MV Africana. The main use of ship time was a squid biomass study. This cruise was subtitled "Predator/Prey Cruise"; its primary objective to provide cross programme links between the Pelagic Ecosystem Studies (PES) and the Higher Predator programme. This was facilitated by the introduction of remote sensing techniques that could give real-time information on sea-surface temperature and the location of satellite tagged predators. This primary objective was approached by investigating the following areas:

(1) The multiple aims of PES long term monitoring programme (specifically resources)
(2) Shipborne observations of sea-birds
(3) The use of remote sensing data

Almost total lack of swarming krill (Euphausia superba) in the Scotia Swa and around South Georgia. Exceptionally low breeding success rates among bird and seal populations but allowed observations of SO food-web when ecosystem was under severe biological stress. Krill not available in high densities. 'Squid/fish' site was oceanic, close to the polar front and phytoplankton biomass was low with nanoplankton dominating. Squid biomass survey -suite of net hauls using a variety of nets with acoustic and oceanographic observations characterized the composition and size structure of the pelagic community in the upper 1000m of the water column. Predator-prey links.

Results:

1. Zooplankton samples were taken with vertically hauled Z nets for copepod egg production and grazing experimen
Chief scientistMartin G White (British Antarctic Survey)
ProjectPelagic Ecosystem Studies
Coordinating bodyBritish Antarctic Survey (BAS)
Cruise reportRRS James Clark Ross JR19943001 (JR06 Leg 2) cruise report jr06.pdf — access key 'C' (7.42 MB) 
Ocean/sea areas 
GeneralSouth West Atlantic Ocean (limit 20W)
SpecificS Ocean; esp. around South Georgia
Track chartsRRS James Clark Ross JR19943001 (JR06 Leg 2) cruise track — trk3951a.html RRS James Clark Ross JR19943001 (JR06 Leg 2) cruise track — trk3951b.html
Measurements 
Physical oceanography 
Surface measurements underway (T,S)Quantity: number of surveys = 4
Description: large scale transects
Surface measurements underway (T,S)Quantity: number of stations = 21
Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients
BathythermographQuantity: number of surveys = 4
Description: large scale transects
BathythermographDescription: XBTs between stations and on passage
BathythermographQuantity: number of stations = 176
Description: (lef 1 and 2 combined) physical oceanographic data measured during CTD casts - surface to near seabed
Water bottle stationsQuantity: number of stations = 14
Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis
Water bottle stationsQuantity: number of stations = 21
Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients
CTD stationsQuantity: number of hauls = 8
Description: microbial production and respiration determined from CTD cast water samples
CTD stationsQuantity: number of stations = 14
Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis
CTD stationsQuantity: number of stations = 21
Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients
CTD stationsQuantity: number of stations = 176
Description: (lef 1 and 2 combined) physical oceanographic data measured during CTD casts - surface to near seabed
Subsurface temperature and salinity measurementsQuantity: activity duration in days = 54
Description: physical oceanographic measurements from 8m depth
Subsurface temperature and salinity measurementsQuantity: number of stations = 176
Description: (lef 1 and 2 combined) physical oceanographic data measured during CTD casts - surface to near seabed
Current profiler (eg ADCP)Quantity: number of surveys = 4
Description: large scale transects
Current profiler (eg ADCP)Quantity: activity duration in days = 54
Description: continuous below surface shipborne ADCP
Current profiler (eg ADCP)Quantity: number of stations = 176
Description: (lef 1 and 2 combined) physical oceanographic data measured during CTD casts - surface to near seabed
Chemical oceanography 
OxygenQuantity: number of hauls = 8
Description: microbial production and respiration determined from CTD cast water samples
PhosphateQuantity: number of surveys = 4
Description: large scale transects
PhosphateQuantity: number of stations = 14
Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis
PhosphateQuantity: number of stations = 21
Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients
PhosphateQuantity: activity duration in days = 30
Description: inorganic seawater nutrients measured - continuous and discrete samples
PhosphateQuantity: activity duration in days = 54
Description: measurements from underway continuous sampling during vessels operation from 8m depth
PhosphateQuantity: number of stations = 176
Description: (leg 1 and 2 combined) measurements from standard depths sampled with CTD rosette - from surface to near seabed or 3000m
NitrateQuantity: number of surveys = 4
Description: large scale transects
NitrateQuantity: number of stations = 14
Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis
NitrateQuantity: number of stations = 21
Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients
NitrateQuantity: activity duration in days = 30
Description: inorganic seawater nutrients measured - continuous and discrete samples
NitrateQuantity: activity duration in days = 54
Description: measurements from underway continuous sampling during vessels operation from 8m depth
NitrateQuantity: number of stations = 176
Description: (leg 1 and 2 combined) measurements from standard depths sampled with CTD rosette - from surface to near seabed or 3000m
NitriteQuantity: number of surveys = 4
Description: large scale transects
NitriteQuantity: number of stations = 14
Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis
NitriteQuantity: number of stations = 21
Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients
NitriteQuantity: activity duration in days = 30
Description: inorganic seawater nutrients measured - continuous and discrete samples
NitriteQuantity: activity duration in days = 54
Description: measurements from underway continuous sampling during vessels operation from 8m depth
NitriteQuantity: number of stations = 176
Description: (leg 1 and 2 combined) measurements from standard depths sampled with CTD rosette - from surface to near seabed or 3000m
Total - NQuantity: activity duration in days = 54
Description: measurements from underway continuous sampling during vessels operation from 8m depth
Total - NQuantity: number of stations = 176
Description: (leg 1 and 2 combined) measurements from standard depths sampled with CTD rosette - from surface to near seabed or 3000m
AmmoniaQuantity: number of surveys = 4
Description: large scale transects
AmmoniaQuantity: number of stations = 14
Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis
AmmoniaQuantity: number of stations = 21
Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients
AmmoniaQuantity: activity duration in days = 30
Description: inorganic seawater nutrients measured - continuous and discrete samples
AmmoniaQuantity: activity duration in days = 54
Description: measurements from underway continuous sampling during vessels operation from 8m depth
AmmoniaQuantity: number of stations = 176
Description: (leg 1 and 2 combined) measurements from standard depths sampled with CTD rosette - from surface to near seabed or 3000m
SilicateQuantity: number of surveys = 4
Description: large scale transects
SilicateQuantity: number of stations = 14
Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis
SilicateQuantity: number of stations = 21
Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients
SilicateQuantity: activity duration in days = 54
Description: measurements from underway continuous sampling during vessels operation from 8m depth
SilicateQuantity: number of stations = 176
Description: (leg 1 and 2 combined) measurements from standard depths sampled with CTD rosette - from surface to near seabed or 3000m
Biology and fisheries 
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of surveys = 4
Description: large scale transects
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of hauls = 8
Description: microbial production and respiration determined from CTD cast water samples
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of stations = 14
Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of stations = 21
Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of experiments = 15
Description: gut evacuation experiments to quantify chlorophyll in copepod
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: activity duration in days = 54
Description: phytoplankton estimates from underway measurements of fluorescence
Particulate organic matter (inc POC, PON)Quantity: number of hauls = 8
Description: microbial production and respiration determined from CTD cast water samples
ZooplanktonQuantity: number of stations = 14
Description: vertical Z nets
ZooplanktonQuantity: number of hauls = 5
Description: LHPR for copepods (0-200m)
ZooplanktonQuantity: number of surveys = 5
Description: twin ship studies, acoustic detection of krill
ZooplanktonQuantity: number of experiments = 7
Description: incubation copepod grazing experiments
ZooplanktonQuantity: number of hauls = 130
Description: vertically hauled Z nets
ZooplanktonQuantity: number of hauls = 8
Description: multinets with 100 specimens measured
ZooplanktonQuantity: number of hauls = 62
Description: gellatinous zooplankton species and distribution
NektonQuantity: number of hauls = 62
Description: composition and size structure of zoonekton
BirdsQuantity: number of surveys = 4
Description: large scale transects
BirdsQuantity: activity duration in days = 30
Description: observations of birds and seals link predators and prey
Mammals and reptilesQuantity: activity duration in days = 30
Description: observations of birds and seals link predators and prey
Pelagic fishQuantity: number of hauls = 62
Description: (from both legs) 2650 caught, composition and vertical distribution of fish
Acoustic reflection on marine organisms.Quantity: number of surveys = 4
Description: large scale transects
Acoustic reflection on marine organisms.Quantity: number of surveys = 2
Description: hydro-acoustic grid - near parallel N-S transects
Acoustic reflection on marine organisms.Quantity: number of surveys = 5
Description: twin ship studies, acoustic detection of krill
Acoustic reflection on marine organisms.Quantity: activity duration in days = 54
Description: continous hydroacoustics of upper water column (EK500)
TaggingsQuantity: number of specimens = 6
Description: Satellite tracking, 4 Grey-headed albatrosses and 2 King penguins
Other biological/fisheries measurementQuantity: activity duration in days = 54
Description: station data, cruise track records etc
Meteorology 
Routine standard measurementsQuantity: number of surveys = 4
Description: large scale transects
Data held at BODC 
Discrete samples 
37  CTD frame plus rosette samplerAmmonium and ammonia concentration parameters in water bodies
Silicate concentration parameters in the water column
Nitrate concentration parameters in the water column
Nitrite concentration parameters in the water column
Phosphate concentration parameters in the water column