EROSPAM (Ka30P) wrote in message ...
My pond, here in zone 7, is about two feet deep.
The ice can get as thick as four to five inches but that is very rare as we
have mild winters. You need to plan for conditions in your area.
Frogs don't bury themselves too much, they just like to snuggle up. So I would
not put in a mud hole in the pond. Turtles and frogs have overwintered in my
pond with just a thin layer of muck down there. Depends on the year but could
have been as thick as two inches.
More important is a hole open in the ice.

http://www.geocities.com/watergarden...dors/home.html

And just how do you keep a hole in the ice on a remote pond? It seems
that we don't get the cold winters we did years ago here but still the
ice can easily get to six inches and stay frozen for many weeks. I
could poke a small hole in the ice but it would freeze up within a
short time. We don't get enough wind to do any wind-powered trickery.