First Nest
I found both mom Kate and dad Petruchio in the nest this morning.
That is dad Petruchio looking out.  You can see Kate to the left and toward the middle of the nest.
Petruchio went across the cove and around the bend, out of sight.
He re-appeared with a bunch of soft grasses for the nest.
Mom Kate had made a nest cup within the main nest before laying her egg(s).
The cup holds the egg(s) securely and keeps them from rolling into possible danger.
The egg cup is made of soft materials and the lining gets packed down.
The parents need to replenish the lining at least daily.
Petruchio delivering his bunch of nest materials.

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.