Common Hibernators:

* Bears: Black bears, brown bears, and grizzly bears are famous for their long winter naps.

* Ground squirrels: Various species, including thirteen-lined ground squirrels and arctic ground squirrels.

* Woodchucks (Groundhogs): These large rodents are known for their long hibernation period.

* Bats: Many bat species hibernate in caves or mines during the winter.

* Chipmunks: These small, striped rodents also hibernate.

* Dormice: These small, mouse-like rodents are found in Europe and Asia.

* Skunks: Some skunk species hibernate, while others may simply become less active.

Less Common Hibernators:

* Hedgehogs: These spiky mammals hibernate in cooler climates.

* Snakes: While not mammals, some snake species enter a state of brumation, which is similar to hibernation.

* Lizards: Some lizard species also enter a state of brumation.

Important Notes:

* Hibernation vs. Torpor: Hibernation is a prolonged state of inactivity, often lasting months. Some animals may enter a shorter period of torpor, which is a temporary state of lowered body temperature and metabolism.

* Not All Species Hibernate: Even within the same species, some individuals may hibernate while others don't.

* Environmental Factors: Hibernation is triggered by environmental factors like decreasing temperatures and food availability.

Let me know if you want more information on a specific hibernating mammal or want to know about their hibernation patterns!