This is a bird in the Eurasian Coot family. I don`t know the exact specie, because of the looks of it. It may be a young bird, without the "white hat" on top of it`s head. This was shot by a known lake in Oslo, the Østensjøvannet, known to have many different bird species. Shot wide open at 600mm about 40 feet away. Which helps with the bokeh.