We walked across the Barrage in pretty hot sunshine but a cool breeze occasionally. At the locks end of the barrage I found 3 Grey Wagtails on the outer barrage rocks, at least one of which was a juvenile. By the maintenance yard at the other end, there were 2 Ravens resting and I took some images of them interacting – I think one [on the right in the photos] was a juv and the adult was seemingly ‘grooming’ it [known as allopreening when it involves a pair]. The usual Sand Martins were busy in the old dock where they nest in holes in the dock walls. We had a coffee in the Lookout cafe and then Anne & I made our back back. During the walk back I had a Rock Pipit on the outer barrage and there were 50 or more Swift distantly over the swimming pool. Just by the inner barrage near the waterbus stop were two large fish [Grayling?]. At Penarth Marina, there was plenty of House Martin activity but it seems that some residents are trying to deter them from nesting under the eaves by hanging glitzy strands of tinsel-like ribbons from their upper window frames, so they blow around and ‘flash’ in the breeze.