| Summary: | Progress Code: completed Statement: During the second half of the cruise the use of the conical nets were discontinued. This cruise provides data from the first of six cruises, which provides a good coverage of the area over varying seasons and conditions. Data collection: Three net types were used for the collection of species; rectangular midwater trawl (RMT8), bongo nets, and conical nets. Routine stations were taken as close to solar midday and midnight. At each station a 'blind' MT horizontal haul at a nominal depth of 62m, an oblique bongo tow from a notional 200 m to the surface, a horizontal surface tow, and a vertical tow with conical nets were taken. Conical surface tows and vertical tows were discontinued in the second half of the cruise due to problems. Ship-board processing: The entire catch was weighed as accurately as possibly immediately it was onboard, and large specimens (medusae etc.) were also individually weighed. Euphausia superba were separated, and the remainder of the catch was sorted into major groups, eg. pteropods, fish, etc., and preserved. A random sample of at least 200 Euphausia superba were, measured, sorted for sex and maturity stage and preserved as a separate sample. The remaining Euphausia superba was either frozen or preserved. Post-ship processing: The catches were sorted into individual species, weighed and counted. Consistency can be established through comparison of different net methods. Oceanography and phytoplankton data were also collected at the net sampling stations, so there is consistency between the oceanography and biology data. The cruise track was established at the beginning of the expedition to eliminate any bias, and was followed as closely as weather and ice conditions allowed. Stations were taken as close as possible to solar midday and midnight. See the attached documentation for more information. This dataset contains results from the First International BIOMASS Experiment (FIBEX) cruise of the Nella Dan. It is the first cruise in a series of six ...
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