The explorers and naturalists who first visited Antarctica were struck by the large numbers of whales, seals and seabirds in such a harsh environment (summarized in Everson, 1977). Scientific expeditions in the twentieth century confirmed these observations, and also established that an even greater abundance of many different trophic levels occurred at the ice edge. Hart (1942) noted that phytoplankton were more abundant near the ice edge mad suggested that there was a distinct ice-edge flora, and Marr (1962) noted that krill (Euphausia superba) were concentrated at the interface between pack ice and open water. Routh (1949) observed that seabirds were very abundant at the ice edge and suggested that the enhancement was due to the high plankton concentrations found in the area. All of these observations suggested that the ice edge played a potentially important role in the ecology of the southern ocean.