by Richard Jones

I was in Peckham Rye Park on Monday and saw a wagtail strutting about by the small stream that runs past.

Richard JonesI was in Peckham Rye Park on Monday and saw a wagtail strutting about by the small stream that runs past. They're not rare birds, but I watched it for some time thinking I had not seen one in ages. Although maybe not really a suburban garden bird, it was quite at home in the ornamental grandness of the recently renovated Rye.

It got me wondering why wagtails wag. A lot of energy is expended twitching about like that so there must be some good purpose in it all. Luckily, the internet birder forums have got there first and there's been a lively discussion on line, in which I'm pleased to note that no solid consensus has been reached.

My first thought was that it might be analogous to the head bobbing used by some larger birds as they strut forwards. This is the equivalent of a human pumping their arms backwards and forwards as they run - conservation of angular momentum, to give it the full scientific title. Sure enough this idea has been mentioned, but so have lots of others.

It has been suggested that tail bobbing might flush out insect prey (they bob more in poor light), be a recognition signal to other wagtails nearby or to disguise them against the rippling and splashing background of the moving water that they regularly frequent.

Who knows? My favourite though, is that they wag their tails because they are happy.

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Gardeners' World Web User 10/10/2008 at 20:05

Although they aren't garden birds "waggies" do come into towns alot during the winter. One dark winter evening I was doing some Christmas shopping and could hear lots of bird noise. Looking up there was a tree full of Pied Wagtails! I assume they had gone there to roost as it was warmer. The amazing thing was the people around seemed oblivious to them.

Gardeners' World Web User 23/10/2008 at 23:19

I had a very unusual visitor to my back yard last summer Richard. It was a wagtail in all its finery,except it had a yellow breast. Saw it two days in a row,and it had what looked like a twig,wedged in its foot. I would love to know what it was ?

Gardeners' World Web User 25/10/2008 at 20:52

Hello Spud, Chances were that it was a yellow wagtail, although it could have been a male grey wagtail. Hope that helps.

Gardeners' World Web User 16/12/2008 at 18:57

can anyone tell me if they have known a grey wagtail to fly at window purposely time and time again, this has been hapening to me foe weeks now.

Gardeners' World Web User 22/01/2009 at 19:28

hi yes i have had a yellow wagtail doing the same to my window since november.

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