The biennial South Georgia Groundfish Survey was undertaken in January 2006 on board the FPRV Dorada. Sixty-three random trawls were undertaken, with 12.3 tonnes of mackerel icesfish caught, which produced biomass estimates of between 91000 and 117000 tonnes. The catches were dominated by fish of 20-25 cm (putative 2+), but unusually large numbers of fish of ~ 50 cm were also caught to the N and NE of South Georgia. Fish in spawning condition (Stage IV) were found at the eastern end of the island and at Shag Rocks. Spent fish were found throughout the survey area, suggesting that spawning may occur from December. The diet of icefish was dominated by Antarctic krill (82 % by weight), with Antarctomysis sp. (A. ohlini and A. maxima) and Themisto gaudichaudii the other main prey species Toothfish catches (548 kgs) were dominated by the same single cohort that was first detected as putative 1+ fish in 2003. The toothfish diet was dominated by Patagonotothen guntheri. Acoustic observations were made in association with both demersal and pelagic data and will help discriminate icefish from other scatterers.
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