Projects/ 4-channel UDDAS

The 4-channel UDDAS (which stands for Underwater Dolphin Data Acquisition System) is an acoustic/video diver-operated recording system developed by Michiel Schotten during his earlier research at the Hawaii Institute of Marine Biology.  With this system, which can be taken underwater by a diver, it has become possible to record the complete frequency range of dolphin sounds up to about 240 kiloHertz, or 240,000 vibrations per second (which is about 10 to 15 times higher than the highest sound that humans can hear – see introduction to dolphin acoustics).

What’s more, by combining the sound recordings from four different underwater microphones (or hydrophones), one can also localize the sounds in 3-D space, and thus attribute the recorded sounds to individual dolphins that are visible on the simultaneous video recordings.  This way it becomes possible to associate different types of sounds with different dolphin behaviors, which solves a number of recording challenges, and is thus a first but crucial step in decoding wild dolphin communication.

A detailed technical description of the system can be found here.  Recordings have been made of Atlantic spotted dolphins (Stenella frontalis) and bottlenose dolphins (Tursiops truncatus) during fieldwork with the Wild Dolphin Project in The Bahamas.  The 4-channel UDDAS has been documented here.  Its realization has been made possible by a number of sponsors who generously donated parts.