Belted Kingfishers make a unique rattle sound. First part of this very short video has one making the rattle on a limb. I repeated it 3 times, zooming in each time to view better. It hardly opens its mouth when making it. Also, they have a nictitating membrane and another cover that protects their eyes as they enter the water, since they hit it so hard and so often. The second part of this video shows their two different eye covers. Again repeated 3 times, zooming in each time. Taken near Hannibal several days ago. If you have HD screen , turn quality up to 2160p for best view.