The distribution and composition of mesopelagic fish assemblages in the Southern Ocean and their relation to major water masses

Fieldwork was undertaken on Voyage 7 of 1997/98 season (April/May 1998) aboard Aurora Australis. The plan was to repeat the transect sampled in September 1996 to investigate seasonal differences between Spring and Autumn. We anticipated being able to sample further south on this voyage because the ice would be at close to its minimum extent.

Sixteen stations were successfully sampled with the MIDOC multiple opening/closing net at 1000-750m, 750-500m, 500-250m and 250-0m depth ranges. The stations were at the following approximate positions: 47o14S:145o43E, 47o57S:145o14E, 49o54S:144o28E, 50o28S:144o15E, 51o15S:144o45E, 52o04S:144o24E, 52o59S:144o52E, 54o00S:145o01E, 53o59S:145o56E, 53o37S:144o32E, 57o00S:145o08E, 59o00S:144o56E, 58o12S:145o44E, 63o41S:139o03E, 64o17S:140o41E, 61o03S:139o40E.

It was originally intended to sample 18 stations, some of which during both day and night, for a total of 26 samples, but consistently bad weather and the necessity to divert to Davis to pick up helicopters prevented the full programme being completed.

However, data for the transect sampled in September of 1996 are available as a collection in the biodiversity database at the provided URL - MIDOC Fish catch from 1996/97 Voyage 1 WASTE (WOCE Antarctic Southern Transect Expedition).