Bald Eagle patrolling Blackburns Resort Dock

I was working on a boat motor very quietly in the winter on Blackburns 170 ft. long dock.  There was no one around and it was very quiet.  I noticed a flock of black ducks around the dock but did not pay much attention to them.  After awhile I heard a swoosh  and then a lot of excitement.  I kept working on the motor an the same thing was repeated.  Again an again.  I looked up and saw a single black duck fly away and was impaled by a very large Bald Eagle.  It was the only one who decided to take flight.  It was fatal.  The rest of them knew enough to just paddle as fast as they could and head for Blackburns.  About a half an hour later the process started all over again.  I do not know if it was the same eagle since they are several winter right across the lake from Blackburns.  It was pretty cool.  I respected the brains of the ducks and at the same time knew the eagle would find one duck that would take flight.  It helped me to think that it was not very good to panic if you are a black duck.  I have also seen several osprey near Blackburns Resort Dock.  They are always in a tree eating a fish.  I guess that is why they are called fisher birds.  Steve