If they buried them behind the dam they shouldn't be an issue.
One other thing. Although now might look like a good time to dig that area out, it might not be. The soil to be packed has to have some moisture to make it pack properly. During the summer, in my arid area, we often can't build ponds. The best mixture is about 60 percent clay and the rest dirt. And, it should be mixed in some way; especially when packing and rebuilding. 100% clay cracks when it is dry and can actually not seal quickly enough.
It's not about the fish. It's about the pond. Take care of the pond and the fish will be fine. PB subscriber since before it was in color.
Without a sense of urgency, Nothing ever gets done.
Boy, if I say "sic em", you'd better look for something to bite. Sam Shelley Rancher and Farmer Muleshoe Texas 1892-1985 RIP
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