| Summary: | Progress Code: completed Statement: The stations provide a fairly complete coverage. This cruise is the third in a series of six cruises, providing a good coverage of the area over different seasons and conditions. This cruise was to have been a more detailed experiment in collaboration with Japan, South Africa and France. Due to resupply problems, sampling had to be reduced. Data collection: Two methods were used for sample collection. A rectangular midwater trawl net (RMT8) was used for the collection of juvenile and adult krill, Euphausia superba. Horizontal tows were also made were krill swarms were located using a Simrad EK 120 echo-sounder. Oblique tows using bongo nets were used to collect krill larvae. Ship-board processing: The large and fragile zooplankton were initially separated from the rest of the specimens, and all specimens were preserved in Steedman's solution. Krill catches from swarms were weighed using a clock-faced spring balance, and part of the catches (greater than 200 specimens) were preserved in Steedman's solution. Post-ship processing: The RMT8 krill samples were sorted into juvenile, male and female, and body length (using a slide caliper) and body wet weight (using a Mettler top-pan balance) were measured. Male and female Krill were further classified into maturation stages according to the system of Makarov and Denys (1981). Non-krill zooplankton in the RMT8 samples were identified to species to the lowest possible taxonomic level. Specimens of juvenile and adult krill were collected using the bongo net. These specimens were used to obtain supplementary body length and maturation stage data, but not for quantitative calculation of biomass or density. Euphausiid larvae were sorted from the bongo net samples, and identification was based on Makarov (1980). The larvae of Euphausia superba and Euphausia crystallorophias raised from eggs in the laboratory were also used as a reference for identification. Logically consistent. Different nets were used to establish consistency and ...
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