In order to get insights into the communication system of a species, we need to study the nature of the signal (i.e. visual, auditory, olfactory, or tactile), the mechanisms of signal production, the medium of transmission (air or water), and functions of signals. Because in an aquatic environment, sound travels much farther than light, cetaceans (whales and dolphins) have strongly increased their sensitivity for acoustical stimuli. In this chapter, I will focus on the techniques currently used for studying the main communication vehicle for whales: acoustic signals.
Keywords: Balaenoptera musculus, Balaenoptera physalus, pop-ups, playback calls, communication in water