Who is he?

Today coming back from the field with my dog Heppu I heard this fellow knocking the wood. I do not know it's name. Someone may tell me. It was rather high up and I wanted to see how my camera acts when trying to get it closer. i am satisfied with "auto" picture.
It was cool still today, but I heard that the weather gets really warm next weekend. We are going with Heppu to learn with other dobermans how to follow the trace in field. New and exiting for both of us!