watched a sea gull pestering an eagle like that once. The eagle did a sudden barrel roll and grabbed the gull when he was upside down. Kept rolling, finished his 360, glided down to the water and landed on top of the gull. then the sort of worked him over with his talons like a baker kneads bread. Took off after releasing the gull and flew away. The gull never moved, just sort of flopped over in the water and drifted away.