South Coast Demersal Biomass Survey on the Africana Voyage 102, April 1992

The South Coast Demersal Biomass Survey was conducted on the Africana Voyage 102 from 31 March to 21 April 1992. The objectives of the cruise were to conduct a random stratified bottom trawl survey to assess the biomass, abundance, and distribution of hake, sole, horse mackerel, squid and other trawl species; to investigate the hydrology and current profiles of the South Coast and to relate this to the distribution of the major demersal trawl species. This included five transects extending from specified areas on the South Coast and approximately perpendicular to the coastline outwards toward the main stream of the Agulhas Current; to survey acoustically the major squid spawning grounds to determine the extent of aggregation of squid shoals at the time of the year; to do a selected number of mid-water trawls to test for the abundance of kingklip and hake and other demersal species as close as possible to the bottom and in midwater over grounds normally inaccessible to bottom trawl gear; to conduct routine biological sampling of the main demersal species; to sample squid intensively to establish their distribution and abundance on the South Coast; to collect shells and other marine organisms for the Mossel Bay Museum; to obtain mature live sole for land-based experimental research and sole ovaries for histological analysis; to collect sharks and rays for the South African Museum; to sample for squid and other fish eggs and larvae using bongo nets; to collect and identify fish species as well as collect unusual specimens for taxonomic work; to do seal observations; and to collect the following specific material for land-based research: Snoek gut contents, Kob, Rocks, South Coast rock lobster, crabs, and any other unusual specimens, echinoderms, mackerel and myctophiids.

南岸底栖生物量调查是在1992年3月31日至4月21日的非洲之旅102号航次中进行的。此次航次的目的是通过随机分层底拖网调查，评估鲽鱼、鳎鱼、鲅鱼、乌贼及其他拖网物种的生物量、丰度和分布；研究南岸的水文和洋流特征，并将其与主要底栖拖网物种的分布联系起来。这包括从南岸指定区域向外延伸的五条测线，大致垂直于海岸线，直至阿古拉斯洋流的主流；通过声学调查主要乌贼产卵地，以确定该年份乌贼群聚集的程度；进行一系列中层拖网作业，以测试近底和中层水层中皇带鱼和鲽鱼及其他底栖物种的丰度，尽可能接近海底并在通常无法使用底拖网工具的陆地上进行；对主要底栖物种进行常规生物学采样；对乌贼进行密集采样，以建立其在南岸的分布和丰度；为莫塞尔湾博物馆收集贝壳和其他海洋生物；获取成熟活鳎鱼用于陆地实验研究以及鳎鱼卵巢用于组织学分析；为南非博物馆收集鲨鱼和鳐鱼；使用邦戈网收集乌贼和其他鱼类的卵和幼虫；收集和鉴定鱼类物种，以及收集罕见标本用于分类学研究；进行海豹观测；并收集以下特定材料用于陆地研究：鳀鱼肠内容物、狗鱼、岩石、南岸岩石龙虾、螃蟹以及其他罕见标本、棘皮动物、鲅鱼和鲀类。