Dolphin Vocalization

As I have been accepted into an internship program this summer in Florida to assist in caring for and training dolphins, I wanted to look into some of the behaviors of these amazing marine mammals. One that particularly interested me was the vocalization used by them for different situations.

In my research, I discovered that there are four typical sound types that dolphins emit, and they are whistles, clicks, burst pulsed sounds, and chirps. Whistles, burst pulsed sounds, and chirps are typically used for communication, while clicks are used for echolocation. Using these sound variations,  researchers can look at many different aspects of dolphin ecology and physiology. One study I came upon looked at whether or not there are metabolic costs of sound production in Tursiops truncatus, and it is the first study to provide empirical data on the subject. The researchers performed 14 experimental trials per dolphin on two adult males and took oxygen consumption measurements. They found that on average, the metabolic rates for each experimental trial were 1.2 times higher in the vocal period than the resting values.

Other studies I found discussed different aspects such as identifying echolocation targets using different learned sounds as labels for the objects. These sounds produced can also be used to identify members of a pod. Typically in these cases, the dolphins use what is referred to as a signature whistle, which can be used by researchers as well to identify the dolphins themselves as they each have unique vocal patterns.

In my presentation, I hope to hit on as many different aspects of dolphin vocalization as I can in my allotted time. There are many studies that have been done on this behavior, and I look forward to potentially seeing some different methods and data collection of this behavior being exhibited by my supervisors at my internship this summer. This area of marine biology dealing with marine mammals fascinates me, and I hope to share some more knowledge about these beloved creatures with the class.

http://www.dolphinear.com/dolphin-vocalizations.html

http://jeb.biologists.org/content/216/9/1624.long

http://scitation.aip.org/content/asa/journal/jasa/131/1/10.1121/1.3664074