Communication and Perception
There are 3 categories of vocalizations used by killer whales: whistles, discrete calls, and clicks. Vocalizations are used both for communication and navigation. They use discrete calls and whistles when communicating within and among pods. Each pod has their a discrete dialect that sounds slightly different from that of other pods. This dialect has been shown to stay the same in a pod for up to six generations. Clicks seem to be used only for echolocation. Killer whales do have good vision, but in dark water their vision is not helpful in catching prey or navigating. As in other Odontoceti, killer whales use sonar to perceive their aquatic environment.
The whale's ears are very small openings behind the eyes, which have no outer flap. The killer whale hears the whistles and clicks through an auditory bulla (earbone complex) in its lower jaw. The sound waves enter through the jaw where they then enter into the earbone complex. In this auditory bulla, there are bones that are like the bones found in the human ear. They waves travel trough these bones, then enter into the brain via an auditory nerve. (Bower, 2000; Deeke, Ford, and Slater, 2005; Estes et al., 2006; Mann et al., 2000; Miller, 2006; Norris, 2002)