Folks if these were strictly recreational ponds I'd welcome all the birds. Problem is they are part of my livelyhood. And as I've said before I use all the persuasive measures I can before the final solution.
I understand completely, Cecil. I would feel very different if a heron could cost me $100-$200 with each swipe of his beak.
I wonder if LGHs are on the increase - I never heard of them when I was a kid, although GBH were very common at a nearby lake we fished. I think a number of bird species, like Crows and Redtailed Hawks, are much more numerous now than they were 40 years ago here. But I was a dumb city boy then, and may not have noticed them much.