Luke-
Thanks for all in advice. I will set up trail cams to see what is lurking. I change out wood chips each year and generally nothing in next but some wasp nest which I take out. occasionally an unhatched egg of unknown species. I dont have any nut trees around which is a bummer. I have planted 300 oak the last 10 years but the they are not fruiting yet. Boarder of pond is generally clean and I dont have any cattails or duck weed. Maybe just not a wood duck place.

Tom