The best way to maintain flight is for a wing to remain level.
But level flight doesn’t offer up a fish from the river.
There are a multitude of calculations and feather changes during a fishing run.
This 4-year-old bald eagle is using some of his feathers on the outer edges of his wing tips as ailerons to control his roll.
Those “ruffled” feathers along the middle of his wings act as spoilers to give him precision for his hunt.
What a marvelous creation.