I moved a few of Mr H's 'dads into my pond already. I assume they would have shown up eventually anyway because I'm only a few hundred feet downstream and it's pretty wet in between.

His pond is 12 years old and there where crayfish in the site before the pond was built. I'm hoping that since they've lived in his pond for so long that it's an indication that they aren't likely to breach the dam.

I'm keeping my pincers crossed.