Mechanism
Structure and Production of Whale Song
Humpback whale songs are made up of notes that are single uninterrupted
sounds lasting a few seconds. The frequency of these sounds vary from
10 to 20 kHz, and the hearing limit of whales can be as high as 24 kHz.
The volume of the songs can reach up to 189 dB. A
collection of four or six notes is called a sub-phrase, lasting about
10
seconds. Two sub-phrases make up a phrase, and a whale will
generally
repeat the same phrase for two to four minutes. This is considered a
theme, a collection of which constitutes a song. A whale will repeat a
song, which can be up to 30 minutes long, for hours or even days.
Activate the image link below to hear an example of a humpback whale
song:
Image courtesy of wikipedia.org
Whales generate their songs by forcing air through their nasal
cavities, producing sequences of low notes which vary in amplitude and
frequency. A song pattern typically lasts 10 - 20 minutes and can be
repeated for hours. A humpback whale's unique song develops gradually
over time, likely both as a result of interaction with other
conspecifics and individual composition.
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