I was very lucky to capture him one morning while I was after the White-capped Water-redstart. That's really two birds with one stone!
The Grey Wagtail (Motacilla cinerea) is a small member of the wagtail family, Motacillidae. The species looks similar to the Yellow Wagtail but has the yellow on its underside restricted to the throat and vent. Breeding males have a black throat. The species is widely distributed, with several populations breeding in Europe and Asia and migrating to tropical regions in Asia and Africa. They are usually seen on open marshy ground or meadows where they walk solitarily or in pairs along the ground, capturing insects that are disturbed. Like other wagtails, they frequently wag their tail and fly low with undulations and they have a sharp call that is often given in flight.
These birds feed on a variety of aquatic invertebrates including adult flies, mayflies, beetles, crustacea and molluscs. They often forage along roadsides in winter, flushing with a sharp chi-cheep call and flying up further along the road but after some distance turning back to return to the original location.