The first time I saw this I did a double take. It was a Northern Parula taking a bath in the ant trap cup above the hummer feeder. It was definitely taking a bath, going in and out, water splashing. There are two ground baths and one pedestal nearby yet it preferred the "intimacy" of the water filled ant trap. Go figure. It came back on three more afternoons, and this time I was ready with the video camera. I never thought of them as a yard bird that's why I wasn't sure of my initial ID. This is definitely a first for me.