Was out for a bit today, saw something that had me doing a double take. Saw a splash ahead of me, wasn't really paying attention, assumed it was a riser. Was looking out on the water and saw the "riser" pop up, it was a goose. Swam really low in the water, so I motored a little closer to make sure it was a goose, and splash, under it went. Popped up again, same deal. Would stay under a bit, and cover a good distance under water. Figured it was wounded or something, (no young nearby, seen them swim low with goslings around..) so I kept my distance. Heading back in, about 10 minutes later, same thing.. (no, not the same bird..) Never seen that before.