Pied Wagtails in the Dark

At 5pm this evening I was coming out of the side of Reading Station (the tradesman's entrance - I find it quicker than trying to fight my through the concourse to get to the main entrance).  It was already dark and, as I was about to cross the road, a flock of 30 - 40 small long-tailed birds flew up into the air and then alighted again on some bushes near the RailAir Bus terminal.  Their general behaviour reminded me of a flock of starlings but they were whitish against the black sky.  I went over to the bushes to get a closer look and saw that they were pied wagtails - a whole flock of them in Reading town centre at night!  I suppose that they were migrating south as a group in order to escape from the recent cold weather.

Update on Tue 2004-12-21 by Tristram Brelstaff

This morning at just before 7am I saw two pied wagtails on the same bush as the flock settled on yesterday evening.  The rest must have moved on during the night.