Watch the interview with Dr. Whitlow Au
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About Dr. Au
Dr. Whitlow Au is the Chief Scientist for the Marine Mammal Research Program at the Hawaii Institute of Marine Biology. Dr. Au has studied the mesopelagic boundary community and the acoustics of snapping shrimp, but his primary research is sound production and reception in whales and dolphins. His book, The Sonar of Dolphins, describes dolphin echolocation in detail. Dr. Au’s research focuses on how dolphins produce, detect, and use sound to understand their environment. He has also examined the effect of sound on whales and dolphins.
Dolphin Sound Production Research
Dr. Whitlow Au studies sound production and reception by marine animals, concentrating on dolphins. His work has examined the ability of a dolphin to transmit, receive, and process sounds. Dr. Au discovered that a dolphin changes its echolocation clicks depending on how far it is from to its target. A dolphin decreases its click interval (the amount of time between successive clicks) and decreases the amplitude of the clicks as it nears its target. Originally, it was thought that dolphins made clicks less often when they were further away because they were trying to remain hidden. Dr. Au, however, showed that it is a result of the way dolphins process information from their clicks. A dolphin waits until it hears the echo from a click before making another click. Therefore, as a dolphin approaches its target, the distance between the animal and the target decreases, allowing the dolphin to decrease its click interval. As this is occurring, the dolphin also decreases the amplitude of its clicks. Dr. Au has compared dolphin echolocation to bat echolocation and other types of sonar to study similarities and differences between various animals.