Until recently, what we knew about the lives of baleen whales in the Southern Ocean was chiefly based on research conducted during the Antarctic summer. The reason: in the winter, there were virtually no biologists on site to watch for the animals. Experts from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) have now used permanently installed underwater microphones, which have been recording for the past nine years, to successfully gather and analyze whale observation data from the Weddell Sea.