It will probably depend on how noticeable the change is. Sleep/wake cycles are broadly controlled by internal clocks whose timing is synced to day/night cycles via light sensing cells different from those we use to see with.
From personal experience, though, most of us probably know that a bright light in the middle of the night can wake is even if we are nowhere near the point in our circadian cycle where we would be waking up. But a dim light, like a candle, probably won't.
So, I'd expect nocturnal animals in places that are already fairly dark, such as bats that live in caves, to probably sleep right through it, because it will only make a minor change to the light in the cave. Nocturnal animals that live in more exposed places might react, either to the change in light or to the change in temperature.
A bit of Googling indicates this may indeed be the case. Cave bats usually don't react. Forest dwelling bats have been seen to come out.
It would be interesting to do some experiments to see if it is the change in light or the change in temperature that is waking them.
From personal experience, though, most of us probably know that a bright light in the middle of the night can wake is even if we are nowhere near the point in our circadian cycle where we would be waking up. But a dim light, like a candle, probably won't.
So, I'd expect nocturnal animals in places that are already fairly dark, such as bats that live in caves, to probably sleep right through it, because it will only make a minor change to the light in the cave. Nocturnal animals that live in more exposed places might react, either to the change in light or to the change in temperature.
A bit of Googling indicates this may indeed be the case. Cave bats usually don't react. Forest dwelling bats have been seen to come out.
It would be interesting to do some experiments to see if it is the change in light or the change in temperature that is waking them.