Click on the link above the Graph to hear the song of the Humpback whale.
The following article is extracted from 'Ear on the Sea' E-zine (available for FREE - Click on the Banner above)
Without a doubt, the most interesting aspect of the Humpback
whale is it's song. Only males sing! So it is assumed they use
their songs to attract females and discourage other males. These
songs last upwards of 30 minutes and are composed of 2 to 10 main
components - always repeated in the same order. The song changes
slowly over many months but the songs remain recognizable to the
one sung last year. Over a period of five years, or so, the
songs are completely different.
In any given breeding ground, there's an almost infinite variety
of timbre, volume and frequencies to be heard. All of the males
in the area sing the same song. Small variations sometimes occur
which are picked up by the other males allowing the songs to
evolve over many years into new tunes.
If you watch a male singer, you'll see him surface for air, then
dive under the surface to a depth of 15 metres or so. There with
head pointed slightly downwards he begins his song.
Why do they sing? No one has yet deciphered the exact message,
but it seems likely that songs attract mates. In the breeding
grounds one often sees a female, a calf and an 'escort'. Many
scientists believe that the 'escort' is the male singer who
accompanies the female waiting for her to come into heat after
the recent birth of the calf. If one theory is correct, the
etherial songs are mostly designed to sooth and woo the female
and only secondarily to warn off other males. Other observations
seem to suggest that the songs are a method of establishing a
"dominance hierarchy in the breeding grounds."
SOUND IS EVERYTHING:
All of this is hidden from your eyes. To understand the whale
and all other sea creatures you must listen to their sounds. In
the sea, you might say that senses are reversed. On land, sight
is the most important. You can see much further than you can
hear. In the sea the opposite is true - you can hear much further
than you can see. So whales, dolphins, fish and other creatures
that inhabit the depths have developed very sophisticated sound
transmission and receiving organs. That's why marine biologists
make use of hydrophones to study and record underwater sounds.
It has been said, but is still unproven, that humpback whales can
communicate from 'equator to pole'. Not their songs necessarily,
but other sounds - grunts, bellows, moans - some sounds that we
can hear and some that are below the range of human hearing but
which carry great distances - thousands of miles - in deep
underwater sound channels. If they do, who are they communicating with? Can a whale in a northern hemisphere breeding ground signal its distant cousin in Antarctica? These are questions that are still to be answered.
One thing that is more likely, is that humpback whales are
probably the source of the many legends and myths about sea
monsters. Early sailors would have encountered the the eerie
songs of the Humpback whale and heard them through the hulls of
their ships. The Humpback whale's voice is very strong - much
greater than that of the Gray whale. If you happened to be
swimming near a singing whale your whole body would vibrate - an
encounter that would be guaranteed to feed a myth for centuries!