In general, I think 400-500mm is the absolute minimum you need to seriously shoot the Eagles fishing in the river. It is rare that they fish within about 200 feet of the shooting locations. Anything can and does happen.
It is, however, very common to have eagles perch in trees (often with their catch) very close by. I've had situations where 500mm was almost too much but that is not every day there.
On the bright side, I've spent a lot of time at Blackwater, Chincoteague, and other more or less local spots known for eaglesd (especially Blackwater). If you are ever going to have any chance of getting decent eagle shots with a 70-200, it will be at Conowingo.
How's that for threading a needle?
I have a 300/2.8 AFSII that I would not otherwise be using. You have first dibs on it. Beware the puppy dog though
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