Pelagic Pre-Recruit Mesopelagic Biomass Survey on the Africana Voyage 090, March 1991

The Pelagic Pre-Recruit Mesopelagic Biomass Survey was conducted on the Africana Voyage 090 from 05-19 March 1991. The objectives of the cruise were to get an estimation of the biomass and population structure of epi-pelagic pre-recruit fish off the West Coast by means of echo-integration and midwater trawling; get an estimation of an epi-pelagic pre-recruit biomass index using quantitative Methot trawls; get an estimation of the biomass and population structure of mesopelagic fish using echo-integration and midwater trawling; to investigate the behaviour of pelagic pre-recruit fish in relation to oceanographic variables; get a collection of biological material for age, oil content, diet and condition studies on pelagic pre-recruits; to determine oxygen concentrations in rock lobster distribution areas; the profiling of currents by means of the acoustic doppler current profiler; and testing the feasibility of the acoustic assessment of juvenile hake.