West Coast Hake Biomass on the Africana Voyage 079, January 1990

The West Coast Hake Biomass Survey on the Africana Voyage 079 was conducted from 4 to 29 January 1990. The objectives of the cruise were to survey by means of trawling the abundance of adult and recruiting hake in South African waters, to investigate the diurnal cycle of hake and other demersal species, to investigate the environmental and ecological interrelationships of hake and other demersal species, to make some experimental trawls in deep water to determine hake distribution limits and collect deep-water specimens of fish and squid; to collect routine biological material on demersal species from Namibian waters (if time permitted); to investigate the occurence, distribution and abundance of squid and squid larvae; to study demersal community interrelationships; to study the biology of sharks and selected non-commercial fish species; to investigate zooplankton scattering layers and their influence on the feeding behaviour of small hake; to obtain coverage of chlorophyll-fluorescence distribution at the sea surface as part of an ongoing monitoring programme; to collect data concerning currents on the South African shelf region from as close to the surface to as close to the bottom as possible; and lastly to train oceanographic research assistants.