While researchers have studied dolphin communication for decades, science has only been able to generalize what signals are used during behaviors. This is because technology has not been available to localize or tell us which individual is talking and what signals they are emitting.
When researchers record communication and behaviors, typically a hydrophone and separate video recording device is used. Acoustic and visual recordings are synced, and while some researchers are able to associate physical behaviors to concurrent acoustic signals – neither video nor acoustic recording give an indication on who spoke the signal. So, it has been difficult to say what animals and signals are meant to act as a back-and-forth conversation. However, slowly but surely technology has advanced, and scientists are one step closer to localizing the ‘whistler‘.
Dr. Herzing from the Wild Dolphin Project began preliminary work using a new localizing device. This custom underwater device uses three hydrophones and camera to simultaneously record audio and video. The recordings are interpreted by a specialized software that will identify a whistle in real time. When watching the recording, the software will mark a ‘whistler’ with either: a yellow star if it emits a whistle, or a red square if it emits a click.
Scientists have also developed novel technology capable of tracking the strength and projection of a dolphin’s echolocation. Dr. Amundin and colleagues have been working on the ELVIS project.
The ELVIS system includes an array of hydrophones and specialized software that visually tracks a dolphin’s echolocation beam. A dolphin is given the opportunity to choose a symbol on a screen – each symbol representing a food reward. Upon approach, a dolphin can point via their echolocation and ELVIS will follow the beam, showing both the strength of the signals and indicating the choice.
It is truly incredible the advances we have made in our technology and all the new questions we can work to answer!