I saw this white swan with the fledglings at the Schellbruch. There were two of them and I think it was the parental couple of the fledglings. The swan that protected the fledglings hissed quite loud and expanded the wings to appear dangerous. You probably know it, it’s not harmless to enter their territory, that’s what people say and I think they are right.
I was pretty careful and didn’t show any fast reactions and the swan eventually noticed that I am not a threat and calmed down. There was a footbridge near the swan that you need to use if you want to go further east, I slowly approached that bridge and shot some pictures from there. I attached some in this post but I will upload some more in the future.