Hedgehog hibernationHedgehogs are one of the few mammals that are true hibernators. During hibernation hedgehogs are not really asleep, instead they drop their body temperature to match their surroundings and enter a state of torpor. This allows them to save a lot of energy but slows down all other bodily functions making normal activity impossible.When do hedgehogs hibernate?Hedgehogs usually hibernate from October/November through to March/April. Research has shown that each individual is likely to move nesting sites at least once during this period and so can sometimes be seen out and about. During mild winters hedgehogs can remain active well into November and December.