A hibernating hamster will continue to breathe shallowly and will be limp to the touch, while a dead hamster will show no signs of breathing and will be rigid. Hamsters hibernate in response to changing temperature conditions, and hibernation looks very much like death to the novice pet owner.
Both a hibernating and a dead hamster will be very cold to the touch and will not respond to pokes or prods. It may also be difficult to feel the slowed heart beat or see the shallow breathing of a hibernating hamster. Checking for signs of rigor and attempting to coax the hamster out of hibernation by increasing the temperature outside the cage can help determine if it is still alive.