Page 26 - Complete Birds of Britain and Europe (DK - RSPB)

INTRODUCTION

SONG AND CALLS

irds’ voices are remarkably far-carrying and can
Bconvey a variety of messages to other birds.A bird
will use many vocal sounds but each type is normally
constant within a species.This helps us to use song and
calls to identify individual birds. Usually it is the males
that sing to attract females for mating and to repel
other males from their nesting area.
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UNIQUE INSTRUMENTS
Birds have no voice box or larynx, but
a muscular organ called the syrinx at muscle KEEPING IN TOUCH
the base of the windpipe.A series of Many calls are contact notes,
membranes are stretched and relaxed by SYRINX which are used by birds as
A bird can use the
bunches of muscles, and vibrate as air cartilage muscles within the syrinx, they go about their everyday
passes across them. Some birds have a rings which are attached to lives. Such calls help to keep
flocks and family groups
simple syrinx so produce little variety rings of cartilage, together as they feed or
of song. But complex ones produce to change the sound move about, even when
great variations in pitch and quality. membrane that is produced. they are within thick cover.
VARYING FUNCTIONS AGGRESSIVE DEFENCE
It can be difficult to distinguish between a Loud, harsh cries are given by terns, gulls, and
song and a call but basically they have different skuas, such as this Long-tailed Skua, when they
functions.A song is primarily used to attract a chase intruders that venture too close to their
mate or to defend a territory. It can be varied nests. Their alarm notes have an obvious urgency,
sounding hysterical if their chicks are threatened.
and intricate, made up of a complex set of
notes. Calls are usually simpler and are used to
pass on information – such as an alarm call
warning of a predator. Such calls are high and
thin, to penetrate through dense woods. Birds
also call in flight, purely to keep in touch.
CONSTANT REPETITION
The Song Thrush is easy to identify when in song.
It sings a few notes – mellow or loud and
challenging – in a short phrase. Each quick burst
of notes is repeated two or three times before
another theme is introduced.

UNMUSICAL PERFORMANCE
The Fulmar sits on its nesting ledge and greets its
mate as it flies by, or settles alongside it, with a burst of
raucous, throaty cackling. To us the calls are coarse and
unmusical, but they probably help Fulmars to identify
each other and are an important part of courtship.

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