So...I'm looking after a corn snake kept at a small zoo. The enclosure/house it is kept in is not weather-proofed at all. It's very well shaded so the summer sun doesn't heat it up too much...but there's nothing that keeps the winter cold out. I've got a heat lamp set up for him now...but the temps fluctuate quite a bit with whatever the outside weather is doing. There is simply no way to keep a steady temp in that building.

Every single time in the past that I've looked in on Tattoo, he's on top of his substrate (aspen) and either sleeping out in the open, or actively wandering around. He's not a snake that feels the need to hide. Now that the weather has cooled and I've installed a heat lamp over one half of his enclosure...I checked on him, and he has completely buried himself under the aspen on the cool side of his enclosure. Temps on the cool side that day were 65*. The warm side was about 80*. These temps, of course, can change drastically. I'm not sure how effective the heat lamp is when the night time temps drop into the 40's or even upper 30's.

My questions:

Is he wanting to brumate? Seems likely to me. Should I let him? If so...this would mean that I stop feeding him, correct? (But I'll keep fresh water available to him.) How cold is too cold, even for a brumating snake? Is there a minimum/maximum range of temps I should TRY to maintain for him?