The osprey fledgling wandered into the wrong territory.
The mother osprey of the nest he tried to get to took exception to his visit.
Firmly, but without any damage to the youngster,
the adult osprey escorted the juvenile away from her nest.
Notes:  the juvenile is in the lead;
 he is much smaller, because he is a male – not because he is younger
when you can see their backs, the youngster has a white line that bisects his wings.
I call these white spots “rivets”.  They are camouflage spots at the end of his feathers.