The oceanographic sampling is part of a long-term monitoring program that started in 1991, during which the water column in Potter Cove is sampled weekly in summer and bi-weekly in winter, whenever the meteorological conditions allow it at several sampling stations in the Cove. A Sea-Bird SBE CTD (Sea-Bird Electronics Inc., USA) was used for data on seawater temperature and conductivity (transformed in salinity). Average Sea Surface Temperature (SST) and salinity were extracted from the upper meter from the long-term monitoring station in inner Potter Cove (E1).