Thanks for your replies. The frogs were taken as froglets from a petshop and put in the pond since April. Never have they been inside, so I'm not sure if it'll be a stressful experience.

The pond is about a foot and a half deep, I live in the sub-tropics of Taiwan, and it never freezes in the winter. Last winter I hibernated my turtles out there unscathed. They just brumated at the bottom.

I wonder if by putting leaves and debris along the banks of the pond if they'll hibernated there? Otherwise, before autumn's end, I'll dump debris in the pond to give them extra insulation.

I'm just afraid the turtles might nip at them.

So far, there've been no encounters, I've raised both together beore, and bullfrogs are extra wary creaturew with a sharp survival intelligence. I've never hibernated them though.

Any more suggestions would help.