The slow pace let me get a good long look at an erect duck, quite a different kind and a crowd of cygnets and parents at a lock gate hissed at me as I crossed. They had moved off by the time I needed to open the gate though. I also got a good look at a different purple plant and asked Bryn if it was Himalayan balsam. This was a plant he had to clear from the water of Leith in large quantities. He confirmed it was, but many of his distinguishing features were based on the work to clear them, the shape of the stem, how it breaks, how easily the plant uproots, none of which I was observing. They were pretty flowers though and he did manage to zoom in on those to confirm.