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Description:
The Song Thrush
is a small to medium sized member of the thrush family, being
smaller than Blackbird, slightly larger than a Redwing and
about 15% smaller than a Mistle Thrush. Song Thrushes usually
have warm-brown upperparts, although some individuals show
colder tones more akin to those seen on the Mistle Thrush.
The underparts are predominantly white, with a warm brown-buff
wash on the sides, which extends and strengthens in colour
under the wing (this is distinct from the strong red-brown
colour seen in the Redwing). The brown spots on the underparts
tend to arranged in lines on the flanks. The tail is proportionally
shorter than in the Mistle Thrush and lacks any obvious white
colouration.
The song consists
of a series of vigorous, simple phrases, less rich than that
of the Blackbird, but with a penetrating quality. The fluting
notes are often interspersed with harsh, impure tones and
some mimicry of other species.
Ecology & Behaviour:
As a garden bird,
the Song Thrush is most likely to be seen alone or in pairs,
although during the winter, groups may feed alongside Blackbirds,
Redwings and Fieldfares. Song Thrushes are usually seen feeding
on the ground, or heard smashing snails against stones. The
flight is typically fast and direct and may be accompanied
by a short call note.
Song Thrushes
can be very early nesters and the young may be on the wing
by the end of March in a good season. In common with other
thrushes, mud is incorporated into the nest but the Song Thrush
does not bother with a grass lining – she lays her lovely
blue eggs onto a smooth mud inner surface which makes their
nests quite easy to recognise.
Careful analysis
or BTO ring-recoveries has shown that poor survival of young
birds through their first winter could explain the observed
drop in the Song Thrush population. Between 1962 and 1973,
winter survival probability for first year birds was 48.4%
compared to only 40.5 between 1975 and 1993 – a drop
of nearly 20%. There does not seem to be any comparable decline
in nest productivity or in the survival rate of adult birds
once they have made it through this winter bottleneck.
Garden BirdWatch links
A 'Focus On' article on the Song
Thrush appeared in issue 10 of the Bird
Table magazine. Garden BirdWatch participants can download
a copy of this article from the participant only pages.
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