| Title | West Coast Demersal Survey on the Africana Voyage 133, January 1996 |
|---|---|
| Authors |
Cooper, R |
| Publisher | Department of Forestry, Fisheries and the Environment (2026) |
| Contributors |
Contact Person: Tutt, Gavin Project Leader: Lamont, Tarron |
| Abstract | The West Coast Demersal Survey was conducted on the Africana Voyage 133 from 12 January to 20 February 1996. The objectives of the cruise were to survey by means of trawling the abundance of adult and recruiting hake in South African waters; to conduct routine biological and length frequency sampling of demersal species; to investigate the environmental and ecological inter-relationships of hake and other demersal species; to investigate the occurrence, distribution, reproduction and abundance of squid species; to investigate the distribution and biology of demersal species in water at depths greater than 500 m by means of demersal trawling; to sample catches for hake sex ratios and frequency of gill parasites; to conduct demersal environmental studies including intercalibration of bottom temperature measurements with commercial trawlers, CTD and ADCP measurements at ALL trawl stations and other specified stations, and box cores and transmissometer profiles at HODSA sites on the Namaqualand coast; the collection of specimens for the South African Museum; the sampling and collection of larval nematodes from squids and the sampling of anisakids from various fish species; to intercalibrate the trawling gear performance of FRS Africana and Dr Fridtjof Nansen by means of joint trawling in order to enable the comparisons of biomass estimates by the two vessels and the estimation of total hake biomass for the region; to estimate demersal fish biomass and, in particular, hake biomass using echo-integration techniques, and compare them with bottom-trawl estimates; to estimate the proportion of the hake population above the headline of the demersal sampling gear, investigate the causes for the pelagic behaviour of Cape hakes and determine prevalent areas of occurrence; and to carry out intercalibration exercises between AIDA, interfaced to the Simrad EK400 echo-sounder system, and the EP500 post-processing system interfaced to the Simrad EK500 echo-sounder system. |
| Data | |
| Temporal extent | 12 Jan 1996 – 20 Feb 1996 |
| Geographic extent |
Benguela Current Large Marine Ecosystem
North: -28.5 |
| Keywords | Africana , OCEANS , SOUTH ATLANTIC OCEAN , West Coast Demersal Biomass Survey |
| Related resources |
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