Herons are federal protected migratory birds, but
you may have to just shoot them. I've seen them pull 15 inch catfish out of my ponds. And, for
every snatched fish that I've witnessed, the Herons have probably pulled another ten out.
I've avoided shooting them because the birds are only doing what comes natural for them. And, there are not easily discouraged. They will come in and start fishing with me right there on a running tractor. I tried the decoy suggestion,
but that only attracted them.