The yellow wagtail (Motacilla flava) is a slim and graceful bird that is recognisable from its bright yellow summer colouring and its characteristic running movements with tail and head wagging.
Distribution
and habitat
The yellow
wagtail spends its winters in tropical and southern Africa and its summers in
Europe, where it can be seen virtually anywhere except Ireland and Iceland. In
the United Kingdom it is
found mostly in England
(apart from the far southwest) and eastern Wales . Its habitat is mainly water
meadows, pastures and boggy moorland. It is often present where cattle are
grazing, as it likes to feed on insects that breed in cattle dung, although not
exclusively so.
Loss of
habitat would appear to be the main reason for the decline of yellow wagtail
numbers in Great Britain since the 1980s, which is why the bird is on the red
list of endangered species.
Description
The yellow
wagtail is some 16-17 centimetres (6.5 inches) in length. Males have bright
yellow underparts in summer, and are yellowy-green on top. The colouring of
female yellow wagtails is less bright, with the green colouring tending more
towards brown than on the males. In winter, male yellow wagtails more closely
resemble the females. The legs are black.
There are a
number of distinct subspecies of yellow wagtail, with the differences being
most clearly seen in the colouring of the head feathers. The most common
subspecies seen in the United
Kingdom is “flavissima”, which has a bright
yellow forecrown and supercilia (stripes above the eyes) and is yellow-green on
the main crown and cheeks. Other varieties include blue-headed (“flava”),
grey-headed (“thunbergi”), black-headed (“feldegg”), ashy-headed
(“cinereocapilla”) and white-headed (“leucocephala”).
Behaviour
The yellow
wagtail has a markedly undulating flight although it spends most of its time on
the ground, walking or running with tail wagging and head darting to and fro.
It will sometimes flutter into the air or perch on a fence, wire or bush. When
not nesting, the yellow wagtail is a gregarious bird and it will roost
communally, with sometimes as many as a thousand birds flocking in reedbeds
near ponds and lakes.
Food for
yellow wagtails consists of beetles, caterpillars, spiders and small molluscs.
The yellow wagtail
has a loud “twee-ipp” call and a short irregular warble. The call can be heard
on the appropriate page of the RSPB (Royal Society for the Protection of Birds)
website.
Breeding
Yellow
wagtails return to their breeding grounds in late March or early April, when
they form smaller flocks that later break up as pairs form to establish nesting
territories that are vigorously defended by the male birds. A nest is built by
the female yellow wagtail on the ground in May or June. This comprises a
structure of grass stems lined with soft material such as animal hairs, wool or
feathers. The whole construction will be concealed in a clump of grass that acts
as a roof.
Four, five or
six eggs will be laid, these being incubated by the female alone for up to 14
days with the male standing guard close by. Both parents feed the young, who
leave the nest after about 10 days although they will continue to be fed by
their parents for another two weeks or so before they fledge. A second brood is
often raised. They leave for their winter quarters in August or September.
© John Welford
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