I was very concerned about Blue Heron until I faced a much more deadly enemy the "water turkey" / Anhinga.

I have concluded for me the Herons are a minor nuisance eating frogs, snakes, minnows, and a few small fish vs the Water Turkeys in relatively large groups diving under the water and eating lots of small to medium size fish.

As far as the herons I have had moderate luck with the alligator decoys....
I still use the gator decoys and think my problem with herons would be worse without them.
In my experience the herons are much more afraid of humans than the water turkey.
Although water turkey tend to be seasonal and herons are around pretty much year around.

Alligator Decoys




Fishing has never been about the fish....