Processed CTD continuous observations from the West Coast Hake Biomass Survey on the Africana Voyage 069, January 1989

Here we present processed downcast Conductivity-Temperature-Depth (CTD) continuous data collected between 05 and 26 January 1989 during Voyage 069 on the FRS Africana, in the Benguela Current Large Marine Ecosystem (BCLME) region on the west coast of Southern Africa. Neil Brown MK3 and MK4 CTD instruments were used to measure pressure, temperature and conductivity through the water column during research and monitoring cruises between 1983 and 2000. The West Coast Hake Biomass Survey was multi-disciplinary. The main target was to determine, by means of the swept area method, the present status of the hake resource on the South African west coast. In carrying out this study, it was possible also to collect some information on the environment and zooplankton (including squid larvae) in the vicinity of the catches and to determine some ecological interrelationships of hake and other demersal fish species, to investigate squid distribution, to study some aspects of the biology and distribution of sharks and skates, to study the feeding ecology of demersal species of little commercial importance and to look closely at demersal communities. A diurnal study was also carried out successfully and some deep-water trawls were made to collect rare and interesting specimens. While in South West African waters, a comparison of the trawling capabilities of the M.F.V. Chica Touza and R.S. Africana was attempted and much biological material was collected for routine studies of demersal fish in those waters. Throughout the cruise, otoliths and squid beaks were collected for stomach content studies, and in-depth research was conducted into horse mackerel.