Note on maturity of krill in relation to interannual fluctuations of food environment in the seas around the South Shetland Islands

Relationship between food environment and maturity of krill around the South Shetland Islands is discussed. Data during 91/92 austral summer shows that when chlorophyll concentration in fraction larger than 2um was high, feeding activity of krill was also high in the natural environment. 5 years data from commercial krill trawlers indicates that percentages of occurrence of gravid female was high when the feeding activity of the krill was high through out the season.
Therefore, interannual fluctuations of maturity populations are governed by the food environment, the phytoplankton stock in the size fraction larger 1 in krill namely by than 2um.