Your frog definately isn't hibernating. His eyes are wide open and it doesn't look like he has any sort of coating on him. When they hibernate (brumate - I can't spell, sorry) they will try to bury themselves in the substrate and stay that way until they are ready to come out. Last winter our pac man frog, Gordito, went into hibernation in December and didn't come out until late April. Saved on mice though
...she buried herself in 6 inches of gravel so all you could see if you looked really closely was her eyes that slightly stuck up. This year all three of our frogs are already in hibernation, although Spud isn't in as deep due to the fact that he's next to a cage with a heat source at that end. The first picture is of Spud where youc an see that she's shiny, although her eyes are open. The second picture is of Diablo (he's in full hibernation) and if you look very closely you can see where his eye is shut in the bottom of the picture. We don't keep more than 2" of substrate in their tanks at a time which is why they aren't buried fully. Our house is kept around 70 degrees so they'll be fine over the winter. Hope this helps! Let me know if you have any other questions. I don't expect these guys to eat again until March or April.
Spud

Diablo (sorry it's fuzzy!)

~Katie
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2.0.1 Cornsnakes
0.3 Leopard Geckos (Cutie, Lily, and ?)
0.0.1 Savannah Monitor (Sam)
0.2.1 Pac Man Frogs(Gordito, Spud, and Diablo)
0.0.1 Giant Millipede (Mega)
lots of snails and fish...