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.

Moment of Decision
 
The branches of the trees lining the Haw River were tangled thickets of slate and branches of twisted nickel.
The sky was a shade of grey that gave little definition to the morning.
Abruptly the stillness was broken.
I had not seen the adult bald eagle until he moved.
He was a sharp-winged exclamation point of brilliant white head and flared tail in all the palette of grey.
I took the shot and he disappeared toward the river, leaving behind this image of his decision in my mind.

I was out checking nests today.  Didn’t see any parent birds.
But, in one of the coves this 2-year-old bald eagle showed up.
He came zooming out of a bend in the cove, made a low pass over the water, but didn’t fish.
With a lot of momentum, he headed for a landing up in a tree.
Oops. He grabbed the branch but hadn’t lost enough speed and couldn’t stick the landing.
My next shot of him was very blurred as he fought to stay on the branch but ended up flying away. I deleted that photo.