Pied wagtails are fairly common at Croome. There is however another form of this wagtail called the white wagtail (which is confusingly not white). The main difference between the two is that adult pied wagtails have a black back, and adult white wagtails have a distinctly grey back. Juveniles tend to be all sorts of shades of grey so you can't easily distinguish them until they are fully grown.
I spotted a small flock of these wagtails feeding around the feet of the resident cattle at Croome (those are its feet in the background). This behaviour is very similar to the yellow wagtail (but these clearly are not yellow!)
