I was throwing treats in a pond for a huge koi carp, trying to lure it closer for a picture. Evidently pup had been observing this. One treat ended on a lily pad and then DDog suddenly started swimming, smelling it and eating it while swimming (without freaking out) from the lily pad then calmly swam back. I never expected him to just do it. I had tried it with toys several times but he wouldn't leave the security of his footing until now.
Then he just sat in the water, decorated with algae, maybe processing what just happened?
He did it several times after, just going for a swim. He surprised me in this.