It looks like the robin and grackle young have fledged. Today there is a marked uptick in bathing activity at the grotto. This youngster (a starling) has been dancing around the waterfall trying to find a spot where it can mimic the older birds. Robins and mature grackles dominate the two ideal bathing spots. The shaky, poor color video is due to me filming this with my SLR through the window.