Preliminary results on the composition and abundance of the krill stock in the southern Bellingshausen Sea (Antarctic, CCAMLR Subarea 88.3)

Krill sampling was carried out onboard RV ‘Polarstem’ from January 25 to March 11, 1994 south of 66°S, between 68°W and 120°W. Krill Euphausia superba abundance and biomass was in the lower range of values generally found in the Antarctic Peninsula and Elephant Island region. A distinct spatial separation for size groups was observed for krill, with small size groups being more abundant in the East Wind Drift zone and larger ones further north under the influence of West Wind Drift waters. The overall krill length frequency distribution was similar to the composition reported from the South Shetland Island region for the same summer period. The recruitment index for krill indicated a poor recruitment success of the 1992/93 year-class in the region (R1 = 0.076). Both results indicate large scale effects on the krill stock. Spawning was late during the studied season, no larvae were found in the area. These findings were discussed in the light of recently described correlations between winter sea-ice conditions, krill spawning and recruitment success and let to the conclusion that recruitment of the 1993/94 kri11 year-class will be poor.