Species of the day: Pied Wagtail

By James Duncan

Learning & Engagement Officer

The chirpy Pied Wagtail (Motacilla alba) is a bird summed up nicely by both its common and latin name, translated quite literally to 'white wagging tail.' The Pied Wagtail is actually a British breeding subspecies (yarrellii) of the more widely distributed White Wagtail, a species found extensively across the Palearctic, Asia and North Africa. It's a bird that has many names in folklore, including the widespread "willie wagtail" and charming "peggy dishwasher." The second of these is thought to have derived from a time when clothes, pots and dishes were washed by a stream or village well. Either the Wagtails' pied plumage resembled a maid's apron or more likely, the rhythmic bobbing motions of attending birds imitated those of the cleaning being carried out. Whatever the reason, the Pied Wagtail is a bird frequently found near water, enthusiastically and energetically chasing insects, flicking the characteristic tail. Of course, this behaviour isn't unique to the Pied member of the family and there's a number of possible, and still disputed reasons for that 'wag.' It may serve as a useful device for flushing out and disturbing insect prey when on the ground. Equally it may prove useful to signal a bird's level of alertness and vigilance to predators. It may to a lesser extent even signal social status and assist in attracting a mate.

Water-based habitats aside, the Pied Wagtail is typically a bird of open country and farmland though is of course a remarkably familiar sight in urban areas. Its cheeky, exuberant habits have helped it take advantage of living in close proximity to us, where ample opportunities for both feeding and nesting exist. You may spot them in their search for easy-pickings, in the form of dead insects on cars, or fulfilling their reputation for selecting an unusual nest site (preferably a hole). Like Blue Tits and Robins, they may nest virtually anywhere, no location too bizarre or out of bounds. Their conspicuous sense of tireless activity makes them unmistakable, something captured beautifully by English poet John Clare in 'Little Trotty Wagtail.' Here's an excerpt -

"Little trotty wagtail he went in the rain,
And tittering, tottering sideways he neer got straight again,
He stooped to get a worm, and looked up to get a fly,
And then he flew away ere his feathers they were dry."

The Pied Wagtail is what's known as a partial migrant, with birds in the northern uplands leaving breeding territories and moving south during the winter, whereas most individuals in the balmy south are largely resident all year round. Like all passerines, they need to keep warm through winter as their diminutive bodies lose heat quickly owing to the ratio between surface area and volume. To that end, Pied Wagtails are renowned for their huge communal roosts. Though this can happen even in summer, winter aggregations of many thousand are not uncommon and this may occur not just at natural sites, such as reed-beds, but within the hustle and bustle of our towns and cities. They're predominantly taking advantage of a phenomenon known as the 'urban heat island' effect, where heat loss from buildings raises the surrounding ambient temperature. There is of course safety in numbers and individuals struggling to find food will almost certainly find benefit in 'information sharing', even if that means nothing more than following others to feeding sites.    

Pied Wagtail - male © Derek Middleton