A little grebe on the lower pool at Perton.
It seemed to be hanging out with one of the the groups of mallards. When I first saw it, I actually thought it might be an untimely duckling.
It was also fishing in an unusual way. Instead of diving, submerging completely, it was just dipping its head under the water. It was coming up with something and eating it, but I was too far away to see what the prey was.