DEMOGRAPHIC STUDIES OF ANTARCTIC KRILL IN THE SOUTH ORKNEY ISLANDS AREA 2009, FIELDWORK AND PRELIMINARY RESULTS

This study documents methods and data collection during commercial Antarctic krill (Euphausia superba) fishery with the vessel “Saga Sea” in the South Orkney Islands area. We present preliminary results regarding krill demography from the sampling period in January-March, 2009. Total body length was measured from 7520 individuals and ranged from 16-58mm (average: 47 ± 4.5mm). Sex and maturation stages was determined from 4678 individuals and consisted of ~19% juvenile and sub adults, ~17% adult males and ~64% adult females (overall adult sex ratio: 1:4). The proportion of immature krill was similar throughout the study period; whereas the proportion of males decreased and the female proportion increased. This field work was part of the Antarctic Krill and Ecosystem Studies (AKES) and the purpose was also to explore the possibilities for using commercial fishing vessels as a research platform in the Southern Ocean.