Bioacoustics is the study of sound produced by living organisms and how sound affects them. It’s an important area of research especially in the marine world as sound is amplified underwater and acoustic interactions are thought to be just as important as visual interaction.
Cetaceans produce 3 distinct types of noise:
Whistles – This type of repertoire is considered to be used for social communication and individual recognition. Dolphins have signature whistles that are unique to each individual and are used to distinguish between members of the pod. This applies for interspecies and intraspecies recognition.
Echolocation clicks – echolocation clicks are used for spatial orientation as well as finding prey. This type of communication repertoire reflects off the prey and back to the cetacean and thus providing spatial information.
Burst pulses – Burst pulses have many different forms but they are all a series of very rapid clicks, indistinguishable to the human brain, that are thought to be used for social communication. They are the most produced vocalization, however, they are the least studied as well.
My project is using the array hydrophone, which is a 4-hydrophone system used to passively monitor high and low frequency sounds in order to collect recordings and compare how Delphinus delphis, Stenella coeruleoalba and Tursiops truncatus use burst pulses. The first step of this project is to analyze the recordings we have that include burst pulses and try to categorize them based on different parameters such as peak frequency, minimum frequency and duration. Once the burst pulses have been categorized then we’ll be able to compare the use of them between species.
This is an important area of research as so little has been done on it before, therefore it can be used as a baseline for future studies for example, research investigating anthropogenic impact on cetacean communication.
Beth Jones,
Bsc Biological sciences, University of Cardiff, Wales
