Yellow Wagtail  (Motacilla flava)

The yellow wagtail is a small graceful yellow and green bird, with a medium-length tail, and slender black legs. It spends much time walking or running on the ground. As its name implies, it wags its tail from time to time. It is a summer visitor, migrating to winter in Africa. It appears to have been in decline since at least the 1980s, most likely due to loss of habitat for breeding and feeding. 

I was lucky to see this bird returning to its nest next to a waterfall on the Long Mynd, Shropshire. Unfortunately I couldn't stay for long and watch the pair as they busied themselves feeding their young as the path was very busy and I didn't want to draw attention to the nest.