Title Processed CTD continuous observations from the West Coast Hake Biomass on the Africana Voyage 039, January 1986
Project West Coast Hake Biomass
Authors

Gavin Tutt
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientific Technician; contact details: email: Gtutt@environment.gov.za

Tarron Lamont
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientist; contact details: email: tlamont@environment.gov.za

Publisher Department of Forestry, Fisheries and the Environment (2022)
Contributors

Contact Person: Gavin Tutt
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientific Technician; contact details: email: gtsglider@gmail.com

Contact Person: Tarron Lamont
Oceans and Coastal Research, Department of Forestry, Fisheries and the Environment (DFFE); role: Marine Scientist; contact details: email: tarron.lamont@gmail.com

Abstract This is processed downcast Conductivity-Temperature-Depth (CTD) continous data from the West Coast Hake Biomass on the Africana Voyage 039, collected between 08 January and 05 February 1986. The cruise operated in the Benguela Current Large Marine Ecosystem (BCLME) region on the west coast of South Africa. The objectives of this cruise were to survey by means of trawling the abundance of adult and recruiting hake; to investigate the diurnal cycle of hake and other demersal species; to investigate the environment and ecological interrelationships of hake and other demersal species; to carry out acoustic target identification of mesopelagic species with RMT 8 nets; to make a few experimental trawls in deep water to search for the other species of monkfish and to determine the offshore limit of hake distribution; if possible to rendezvous with Spanish and Soviet vessels and to carry out standardisation trawls in parallel and to conduct net mouth-opening experiments with transducers on each wing of the net.
Methods Neil Brown MK3 and MK4 Conductivity-Temperature-Depth (CTD) instruments were used to measure pressure, temperature and conductivity through the water column during research and monitoring cruises between 1983 and 2000. Temperature was converted from the IPTS-68 scale to the ITS-90 scale, and salinity was computed from conductivity measurements on the 1978 Practical Salinity Scale, according to UNESCO (1991) algorithms. UNESCO (1993) quality control procedures were applied to the data, and obvious erroneous values resulting from problems including electronic spikes, data collection in air, inadequate flow through the conductivity cell, among others, have been removed. Any additional calibrations or corrections have been specified in each data file, where applicable and available.
Data
Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
Temporal extent 08 Jan 1986 – 04 Feb 1986
Geographic extent

Benguela Current Large Marine Ecosystem (BCLME) region on the west coast of South Africa

North: -24.0
South: -36.5
West: 13.5
East: 20.0

Vertical extent Max: -740.9 m
Min: 0.0 m
Keywords Africana, Africana 039, Conductivity, CTD, Depth, Neil Brown CTD, SOUTH ATLANTIC OCEAN, Temperature
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