A couple of weeks ago I drove southwards to Mercers Lake, part of the Holmthorpe Sand Pits complex to see if I could catch up with a juvenile Black-throated Diver that had been reported there for some time.
My initial sighting was very distant and this individual never came closer than 100 yards so all the shots posted have been cropped.
Black-throated Diver [juv] (Gavia arctica)
After two partial circuits of the lake, frequently diving for long periods, it reappeared on the south side and spent some time preening before heading away for another diving session.