In this video we see an adult white-tailed eagle (white tail feathers and yellow beak). Firstly the mergansers hurry away from the shallow water because diving ducks simply dive to avoid a danger.
What kind of fish the white-tailed eagle caught remains an open question but silvery scales are visible. The eagle goes to the limestone shelf near the shore in order to get its claws properly dug into the prey. A gull comes to see what fish the eagle caught.