RRS John Murray JM2/80

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS John Murray (74MJ)
Cruise identifierJM2/80
Cruise period1980-05-02 — 1980-05-15
Port of departureBarry, United Kingdom
Port of returnBarry, United Kingdom
Objectives1) To compare the vertical distributions and diurnal migrations of the development stages of Calanus Finmarchicus, Thysanoessa Longicaudata and Sagitta Maxima from the open ocean with Calanus Helgolandicus, Thysanoessa Inermis and Sagitta Elegans from the Celtic Sea.

2) To measure the feeding rates of all species used in the experimental programme under ambient conditions

3) To obtain fresh material for length/dry weight measurements and to deep freeze material for the determination of carbon, nitrogen, ash and calorific content, of all species used in the experimental programme.
Chief scientistBob Williams (Institute of Marine Environmental Research, Plymouth)
Cruise reportRRS John Murray JM2/80 cruise report john_murray2_80.pdf (0.08 MB) 
Ocean/sea areas 
GeneralNorth East Atlantic Ocean (limit 40W)
Track chartsRRS John Murray JM2/80 cruise track — trk2441.html
Physical oceanography 
Surface measurements underway (T,S)Description: Cont. recording on Celtic Sea Site.
CTD stationsQuantity: number of stations = 7
Biology and fisheries 
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of stations = 42
Particulate organic matter (inc POC, PON)Quantity: number of stations = 42
Biochemical measurements (eg lipids, amino acids)
PhytoplanktonQuantity: number of stations = 42
ZooplanktonQuantity: number of stations = 42
Description: also 30 feeding exp.;distribution,biomass,population structures
SestonQuantity: number of stations = 42
Other biological/fisheries measurementQuantity: number of stations = 42
Description: particle size analysis