i guess they will be just fine. i mean, what cold does is that it slows down everything, all the metabolism, but it only causes damage when it gets too cold and some parts shut down completely. everything slows down, and some functions slow down more than others.

a hot spike is much more dangerous and damaging, because some molecules denaturate. this really screws with metabolism and development because specific enzymes that serve specific functions get hit.

in nature, the places where BPs put their eggs have surprisingly constant temperatures. its termite mounds and rhodent burrows, and the climate is very constantly warm and humid around the year, and underground its even more constant.

but i dont see how colder temperatures (nowhere near freezing cold, just colder) for just a limited amount of time could cause any real damage. also in nature, that could happen when a storm hits or something.

by the way, my last power outage was, i dont remember correctly, something like 8 years ago and lasted for 4 hours. in Germany, somehow only the really big high voltage long distance power lines are in the open, everything else is underground.