Rock Pipit (Anthus petrosus), Wilstone Reservoir, Nr Tring, Hertfordshire, 10/10/2012. I spent a lovely, sunny hour or so observing and photographing this bird. It fed voraciously and happily along the NW shore line, occasionally being flushed by walkers/dogs. As a more knowledgable friend pointed out, it had markedly lighter leg colour than on average and was at the low end of range of Rock Pipit size/bulkiness i.e. it actually reminded me more of a Water Pipit in terms of its sleekness.