RRS Challenger CH8/83

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Challenger (74CH)
Cruise identifierCH8/83
Cruise period1983-06-06 — 1983-06-20
Port of departurePlymouth, United Kingdom
Port of returnFalmouth, United Kingdom
Objectives1. To determine the horizontal and vertical distribution of mackerel eggs and larvae in relation to temperature, salinity, oxygen, chlorophyll, light and plankton concentration.
2. To compare estimates of mackerel egg abundance taken by UOR sampling and by standard 20" plankton sampler hauls.
3. To investigate the horizontal variability of mackerel egg numbers and to estimate the point haul variance of standard plankton hauls for mackerel eggs.
4. To determine the density and buoyancy of mackerel eggs through development.
5. To estimate the natural mortality rate of mackerel eggs.
Chief scientistStephen H Coombs (Institute of Marine Environmental Research, Plymouth)
ProjectICES International Mackerel Egg Survey
Coordinating bodyICES
Cruise reportRRS Challenger CH8/83 cruise report ch8_83.pdf (0.18 MB) 
Ocean/sea areas 
GeneralNorth East Atlantic Ocean (limit 40W)
SpecificN.E. Atlantic/ Great Sole Bank
Track chartsRRS Challenger CH8/83 cruise track — trk2920.html
Physical oceanography 
Surface measurements underway (T,S)Quantity: track kilometres = 2222.4
BathythermographQuantity: number of profiles = 54
Water bottle stationsQuantity: number of samples = 4
Description: S surface only
Subsurface temperature and salinity measurementsQuantity: track kilometres = 1666.8
Biology and fisheries 
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: track kilometres = 1666.8
ZooplanktonQuantity: number of stations = 12
Eggs and larvaeQuantity: number of samples = 68
Description: survey:distribution,energy transfers,population
Acoustic reflection on marine organisms.Quantity: track kilometres = 2222.4