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Birdsong Explained
Birds
usually sing to defend a breeding territory
and attract a mate. Birds also make other sounds
usually referred to as calls. These are made at any time of the
year whereas songs are usually heard before and during the breeding
season. Calls can be used to keep a feeding
flock together like the calls of a flock of Long-tailed
Tits moving along a hedgerow. Calls can also be used to warn
of danger such as the loud calls of a Blackbird when
it is startled. Calls are usually short bursts of simple
sounds.
Songs on the other hand are usually very complicated.
Different species of birds have developed different songs. This
enables different species to sing at the same time without confusing
each other. Birds that nest in colonies or loose groups tend to
have less complicated songs. Examples of this type of song would
be Rooks or House Sparrows. Birds that defend a territory tend
to have more elaborate songs.
In
a woodland different species sing at different levels.
For example wrens usually sing from low bushes while Blackbirds
will sing from the top of the tallest trees. This also helps each
bird to be heard by others of the same species. If they all sung
from the same height the songs would be harder to separate and
there would be fierce competition for singing places!
Studies have shown that young birds learn how to sing the song of
their own species though some will rob phrases from other
species. The Starling is notorious for mimicking
other birds and other sounds. They have been records mimicking
car alarms and even a referee's whistle.
Blackbirds and Sedge Warblers also "steal" phrases from other
birds.
Birds
of the same species have been shown to have accents just
like humans. Irish Chaffinches have a different accent
to Scandinavian Chaffinches. The study of recordings of birds
songs have also shown that no two birds of the
same species have exactly the same song. This
is exactly the same as someone from China thinking that all Irish
people sound the same.
Also, birds have to learn to sing, just like we learn to
talk. Young birds practice during their first year and fine tune
it from year to year.
The
dawn chorus is just like an orchestra. The different
species are like different instruments and when all sing together
the sound is amazing.
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