Name: Processed CTD discrete observations from the Shoal Ecology Cruise on the Africana Voyage 018, April 1984
License: https://creativecommons.org/licenses/by-sa/4.0/legalcode

DOI: 10.15493/DEA.MIMS.13122022

Title	Processed CTD discrete observations from the Shoal Ecology Cruise on the Africana Voyage 018, April 1984
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 Conductivity-Temperature-Depth (CTD) discrete data from the Shoal Ecology Cruise on the Africana Voyage 018 collected between 9 and 19 April 1984. 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 obtain a broad picture of pelagic fish shoal distribution in relation to the prevailing mesoscale environmental features; to investigate intensively the diel shoal behaviour pattern of anchovy, pilchard and round herring, with particular reference to their feeding behaviour in relation to food supply. If time permitted the plan was to carry the investigation out in two areas of contrasting environmental features ie St Helena Bay and off Saldanha Bay. Shoals of fish close to strong environmental gradients (in a horizontal plane) will be surveyed to investigate the effect, if any, upon diel behaviour patterns on either side of the gradient. A number of extended lines, traversing the gradient will be steamed with plankton and fish being sampled on an ad hoc basis. It could well be that this investigation would be given a higher priority than the intensive survey off Saldanha.
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) Cite 10.15493/DEA.MIMS.13122022 Style Terms of use These data are made available with the express understanding that any such use will properly acknowledge the originator(s) and publisher and cite the accession numbers and/or associated Digital Object Identifiers. Anyone wishing to use these data should properly cite and attribute the data providers listed as authors in the metadata provided with each dataset. It is expected that all the conditions of the data license will be strictly honoured. Use of any material herein should be properly cited using the dataset’s persistent identifiers such as accession numbers and DOIs. I agree to the terms of use
Temporal extent	09 Apr 1984 – 19 Apr 1984
Geographic extent	Benguela Current Large Marine Ecosystem (BCLME) region on the west coast of South Africa North: -32.2 South: -32.7 West: 17.6 East: 18.4
Vertical extent	Max: -79.6 m Min: 0.0 m
Keywords	Africana, Africana 018, Conductivity, CTD, Depth, Neil Brown CTD, SOUTH ATLANTIC OCEAN, Temperature
Related resources	This digital object is described by https://unesdoc.unesco.org/ark:/48223/pf0000090489 This digital object is described by https://unesdoc.unesco.org/ark:/48223/pf0000138825 This digital object is new version of Raw CTD discrete observations from the Shoal Ecology Cruise on the Africana Voyage 018, April 1984 (10.15493/DEA.MIMS.15122022) This digital object is part of Shoal Ecology on the Africana Voyage 018, April 1984 (10.15493/DEA.MIMS.03122022)

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