Thanks - it appears that what I am seeing fits most of the criteria for eye fluke. I don't think I saw any flukes or abnormalities on the bodies. I did notice a couple of pink spots in the flesh on one of the fish. I have noticed more egret/heron activity than in the past but the pond is in better shape than it has been probably for decades so I figured that was normal. I will start trying to get rid of them when I see them - much to my wife's chagrin.

I bought this place in 2014 with the pond already here and based on talking to neighbors it has probably been here 30 - 40 years. There was a ton of work to do and I have only been focused on the pond for the last couple of years. We originally had a bad water primrose problem but we really don't have a lot of other vegetation. I don't believe there is any structure/habitat in the pond except for some tree branches growing into the water on one end but that is a small area. I cleaned up the primrose by physically pulling it out. Because I don't have much shoreline vegetation or habitat I left 5 clusters of primrose around the pond to provide some cover for the BG and YOY fish to avoid predation. It has been work but I can control the primrose pretty easily now and keep it where I want it.

Do you think it is possible that I have created a snail habitat - the snails distribute the fluke bacteria - that also just happens to be the only place my BG can hide from LMB and CC? Do you or anyone out there have any practical experience in dealing with this? The literature doesn't really imply there is much that can be done outside of killing vegetation and chasing away birds.