I had thought that too, but the AC wasn't turned on until mid June, and I closed the vent in that room just in case, but it changed nothing. The snake sits on top of a wire tool shelf. Below that snake is another my corn snake, below that snake a gecko, and then a hognose snake. The 'stacked cages' all the heat lamp from the under cage to act as an under the tank heater on one end only. The floor of the warm end is around 75 and the cool end is probably about 70 degrees on the floor. All the other animals present, snakes and lizard alike excluding the garter, eat at least once a week as they always have. The garter is the only one having the problem. I've never seen my snake want to eat/so active and take interest in food, but not eat, especially when nothing has significantly changed that I am aware of.