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Wagtails

©Derek Middleton/FLPA

©Mike Lane/FLPA

The grey wagtail tends to prefer more watery habitats than its cousin the pied wagtail.

If there’s a bird walking purposefully, if a little erratically, across your closely cropped lawn, picking up insects and pumping its tail up and down as it does so, there’s a pretty good chance it is a pied wagtail. The commonest of our three wagtail species, the pied is also the easiest to identify: no other British breeding bird has the combination of black and white plumage, slender shape and long tail.

Yet, despite its elegant appearance and endearing habits, the pied wagtail is often overlooked. Perhaps this is because it does not join the tits, finches and sparrows squabbling on the bird table or seed feeders.

Instead, it wanders quietly but efficiently around short grass or pavements, using its sharp bill to grab the tiniest insects and other invertebrates that hide away between blades of grass or paving stones – an ecological niche it appears to have taken for itself alone.

Male and female pied wagtails do have different plumages, though you may need a close look to be of which one you are looking at. Males have a dark, almost black, back, and a black bib and throat contrasting with snow-white cheeks. The female also has white cheeks and a black bib, but her back is greyer. Youngsters have a less contrasting plumage, with a yellowish tinge to the head and face, giving them a rather dingy appearance, as if they forgot to wash.

The other two kinds of wagtail found in Britain are often confused with each other. Both have varying amounts of yellow in their plumage, but while one is, appropriately, called the yellow wagtail, the other, equally attractive bird is saddled with the rather misleading name of grey wagtail. So people often claim to have seen ‘yellow wagtails’ in the middle of winter, when this species has already migrated to Africa, and what they are actually seeing is a grey wagtail sporting a lemon-yellow plumage.

Confused? Well, the name ‘grey’ isn’t entirely wrong: grey wagtails do have a grey head and upper parts, while the yellow wagtail is olive-green above. Yellow wagtails are also much more yellow overall, with the colour extending from the face and throat all the way down the under parts, whereas the yellow on a grey wagtail is confined to the breast and belly. Female grey wagtails, and males in winter, have even less yellow on them: just a small patch underneath the tail.

The two differ in their chosen habitat as well. Grey wagtails are birds of fast-flowing rivers and streams. Like the dipper, they perch on rocks on the bank or in midstream, bobbing up and down before flying into the air to seize an unsuspecting fly. They usually build their nest in a small crack or crevice in the stone beneath a bridge. In winter, they will venture farther afield, sometimes turning up in unexpected places such as shopping-centre car parks, where, like their cousin the pied wagtail, they can find food and warmth.

Yellow wagtails also like water, but of a more sedate kind: they breed in wet meadows, often alongside cattle, whose dung attracts plenty of insect food. Since World War II, much of this precious habitat has been destroyed by being ploughed up for intensive arable or livestock farming. As a result, the yellow wagtail is a much less common sight than it used to be.

Unlike its two relatives, the yellow wagtail migrates south after breeding, heading across the Bay of Biscay and Spain to Africa, where it spends the winter south of the Sahara among the big game of the African plains. In spring, it returns by a slightly different route, crossing the Sahara in a single hop in just three days, before arriving safely back in southern Britain by the middle of April.

During the winter months, the pied wagtail must often cope with very low temperatures and shortages of food. It increases its chances of survival by gathering in large, noisy roosts, often in very light places such as shopping centres or industrial estates, where it can be warm and safe from predators such as tawny owls.

©Derek Middleton/FLPA

The yellow wagtail is a summer visitor to Britain, breeding on wet meadows.