Shot on the second day of Easter. There were four birds protecting two little ones. They chased away people, other birds and attacked a dog. You can see all four of them on another image in this gallery.
I just stood looking at what they were doing at the opposite side of the canal, up to half an hour. They jumped in the water, swam a bit and then came ashore on my side. I kneeled down and after some hissing, angry looks and wing flapping they accepted my presence and I could take some photos from about a metre away. :)