Demography of Antarctic krill in the Lazarev Sea (Subarea 48.6) and the Elephant Island area (Subarea 48.1) in 2004

Standardized krill net sampling surveys were conducted in the Lazarev Sea (Subarea 48.6) in April 2004 and in the Elephant Island area (Subarea 48.1) in January and February/March 2004. Krill densities in the Elephant Island area were below the long-term average which mark a substantial decline after the good krill years in 2001 and 2002. Krill density was lower in the Lazarev Sea, even after taking substantial day/night differences in the catches into account. Recruitment indices of one-year- old (R1) and two-year-old krill (R2) were calculated for both areas, showing low values for R1 and high, but different values for R2. Spatial distribution of krill density and size/age classes is discussed for the Lazarev Sea. Information are given on the development of maturity stages and “re-juvenation processes” after the spawning season. Distribution and density of krill calyptopis and furcilia larvae are provided for the Lazarev Sea.