RRS James Clark Ross JR19943001 (JR06 Leg 2)
Cruise summary report
| Cruise Info. | |
| Ship name (ship code) | RRS James Clark Ross (74JC) |
| Cruise identifier | JR19943001 (JR06 Leg 2) |
| Cruise period | 1994-02-01 — 1994-03-03 |
| Status | Completed |
| Port of departure | Grytviken, South Georgia and the South Sandwich Islands |
| Port of return | Stanley, Falkland Islands (Malvinas) |
| Purpose | Research |
| Objectives | Undertake 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 scientist | Martin G White (British Antarctic Survey) |
| Project | Pelagic Ecosystem Studies |
| Coordinating body | British Antarctic Survey (BAS) |
| Cruise report |  (7.42 MB) |
| Ocean/sea areas | |
| General | South West Atlantic Ocean (limit 20W) |
| Specific | S Ocean; esp. around South Georgia |
| Track charts |  |
| Measurements | |
| Physical oceanography | |
| 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 |
| Surface measurements underway (T,S) | Quantity: number of surveys = 4 Description: large scale transects |
| Bathythermograph | Description: XBTs between stations and on passage |
| Bathythermograph | Quantity: number of stations = 176 Description: (lef 1 and 2 combined) physical oceanographic data measured during CTD casts - surface to near seabed |
| Bathythermograph | Quantity: number of surveys = 4 Description: large scale transects |
| Water bottle stations | Quantity: 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 stations | Quantity: number of stations = 21 Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients |
| CTD stations | Quantity: number of hauls = 8 Description: microbial production and respiration determined from CTD cast water samples |
| CTD stations | Quantity: number of stations = 14 Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis |
| CTD stations | Quantity: number of stations = 176 Description: (lef 1 and 2 combined) physical oceanographic data measured during CTD casts - surface to near seabed |
| CTD stations | Quantity: number of stations = 21 Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients |
| Subsurface temperature and salinity measurements | Quantity: 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 measurements | Quantity: activity duration in days = 54 Description: physical oceanographic measurements from 8m depth |
| Current profiler (eg ADCP) | Quantity: activity duration in days = 54 Description: continuous below surface shipborne ADCP |
| Current profiler (eg ADCP) | Quantity: number of surveys = 4 Description: large scale transects |
| 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 | |
| Oxygen | Quantity: number of hauls = 8 Description: microbial production and respiration determined from CTD cast water samples |
| Phosphate | Quantity: number of stations = 14 Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis |
| Phosphate | Quantity: number of surveys = 4 Description: large scale transects |
| Phosphate | Quantity: activity duration in days = 54 Description: measurements from underway continuous sampling during vessels operation from 8m depth |
| Phosphate | Quantity: 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 |
| Phosphate | Quantity: activity duration in days = 30 Description: inorganic seawater nutrients measured - continuous and discrete samples |
| Phosphate | Quantity: number of stations = 21 Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients |
| Nitrate | Quantity: activity duration in days = 54 Description: measurements from underway continuous sampling during vessels operation from 8m depth |
| Nitrate | Quantity: number of surveys = 4 Description: large scale transects |
| Nitrate | Quantity: number of stations = 14 Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis |
| Nitrate | Quantity: activity duration in days = 30 Description: inorganic seawater nutrients measured - continuous and discrete samples |
| Nitrate | Quantity: number of stations = 21 Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients |
| Nitrate | Quantity: 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 |
| Nitrite | Quantity: activity duration in days = 30 Description: inorganic seawater nutrients measured - continuous and discrete samples |
| Nitrite | Quantity: number of surveys = 4 Description: large scale transects |
| Nitrite | Quantity: number of stations = 14 Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis |
| Nitrite | Quantity: activity duration in days = 54 Description: measurements from underway continuous sampling during vessels operation from 8m depth |
| Nitrite | Quantity: number of stations = 21 Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients |
| Nitrite | Quantity: 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 - N | Quantity: 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 - N | Quantity: activity duration in days = 54 Description: measurements from underway continuous sampling during vessels operation from 8m depth |
| Ammonia | Quantity: number of surveys = 4 Description: large scale transects |
| Ammonia | Quantity: 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 |
| Ammonia | Quantity: activity duration in days = 54 Description: measurements from underway continuous sampling during vessels operation from 8m depth |
| Ammonia | Quantity: number of stations = 14 Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis |
| Ammonia | Quantity: number of stations = 21 Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients |
| Ammonia | Quantity: activity duration in days = 30 Description: inorganic seawater nutrients measured - continuous and discrete samples |
| Silicate | Quantity: activity duration in days = 54 Description: measurements from underway continuous sampling during vessels operation from 8m depth |
| Silicate | Quantity: number of surveys = 4 Description: large scale transects |
| Silicate | Quantity: number of stations = 14 Description: water samples taken at 6 depths 0-200m for chlorophyll and at 6 depths >200m for nutrient analysis |
| Silicate | Quantity: number of stations = 21 Description: total for 2 fine scale transects (83 and 85), water samples for chlorophyll and nutrients |
| Silicate | Quantity: 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 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: activity duration in days = 54 Description: phytoplankton estimates from underway measurements of fluorescence |
| 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: number of hauls = 8 Description: microbial production and respiration determined from CTD cast water samples |
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of surveys = 4 Description: large scale transects |
| Particulate organic matter (inc POC, PON) | Quantity: number of hauls = 8 Description: microbial production and respiration determined from CTD cast water samples |
| Zooplankton | Quantity: number of hauls = 5 Description: LHPR for copepods (0-200m) |
| Zooplankton | Quantity: number of hauls = 130 Description: vertically hauled Z nets |
| Zooplankton | Quantity: number of stations = 14 Description: vertical Z nets |
| Zooplankton | Quantity: number of hauls = 62 Description: gellatinous zooplankton species and distribution |
| Zooplankton | Quantity: number of hauls = 8 Description: multinets with 100 specimens measured |
| Zooplankton | Quantity: number of experiments = 7 Description: incubation copepod grazing experiments |
| Zooplankton | Quantity: number of surveys = 5 Description: twin ship studies, acoustic detection of krill |
| Nekton | Quantity: number of hauls = 62 Description: composition and size structure of zoonekton |
| Birds | Quantity: number of surveys = 4 Description: large scale transects |
| Birds | Quantity: activity duration in days = 30 Description: observations of birds and seals link predators and prey |
| Mammals and reptiles | Quantity: activity duration in days = 30 Description: observations of birds and seals link predators and prey |
| Pelagic fish | Quantity: number of hauls = 62 Description: (from both legs) 2650 caught, composition and vertical distribution of fish |
| Acoustic reflection on marine organisms. | Quantity: activity duration in days = 54 Description: continous hydroacoustics of upper water column (EK500) |
| 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 = 4 Description: large scale transects |
| Acoustic reflection on marine organisms. | Quantity: number of surveys = 5 Description: twin ship studies, acoustic detection of krill |
| Taggings | Quantity: number of specimens = 6 Description: Satellite tracking, 4 Grey-headed albatrosses and 2 King penguins |
| Other biological/fisheries measurement | Quantity: activity duration in days = 54 Description: station data, cruise track records etc |
| Meteorology | |
| Routine standard measurements | Quantity: number of surveys = 4 Description: large scale transects |
| Data held at BODC | |
| Discrete samples | |
| 37 CTD frame plus rosette sampler | Nitrite concentration parameters in the water column Phosphate concentration parameters in the water column Silicate concentration parameters in the water column Ammonium and ammonia concentration parameters in water bodies Nitrate concentration parameters in the water column |
