White Wagtail

 Motacilla alba

Appearance
Black, white and grey plumage 
Black throat and crown

White face

So, apparently there are nine subspecies of White Wagtail. The Moticilla alba yarrellii (Pied Wagtail) is the most common in the UK. However, the Motacilla alba alba (White Wagtail), which is found in continental Europe, migrates through Britain from early March to May and again from mid-August to early November.  Your guess is as good as mine which one this is.  I saw it in Thame, Oxfordshire today. 

Learn more about the White Wagtail. 

Gray Wagtail

Motacilla cinerea

Appearance

Long black and white tail

Gray head and back

Bright yellow belly and vent

Breeding male

     Black throat

     White moustache

While visiting the picturesque village of Castle Combe in the Cotswolds, I spied this bird walking along the shoreline of the river. Not surprisingly, its tail was wagging up and down incessantly. 

Learn more about the Gray Wagtail. 

Pied Wagtail

Motacilla alba yarrelli

Appearance 
Slender bird
Long tail
Black above (very dark grey in female) and white below
White face
Black cap, throat and breast
White outer tail feathers and wing bars
Winter (above)
      Plumage is greyer
      Less black on the breast
      Grey flank
Juveniles (below)
     Often tinged with yellow

I struggled trying to identify these birds which I saw this afternoon on the lovely grounds of The Vyne outside of Baskingstoke in Hampshire.  The yellow face on the one was throwing me off completely. After hours of deliberating,  I finally found a forum on the RSPB website that confirmed its identity (thankfully).

Learn more about the Pied Wagtail.