If you live with a feline companion, you may have noticed them snoozing more during the winter and wondered if cats typically hibernate. Hibernation is a state of regulated hypothermia (or reduction in body temperature) and a slowed-down metabolism as a means of conserving energy, which generally lasts weeks or months. Torpor is more of a temporary process that may appear as sleep, but is a short, involuntary period of inactivity that lasts a few hours during the day in some species based on food availability and outside temperatures.
Animals like bears and hedgehogs that hibernate during the winter experience physiological changes that allow them to spend long periods hidden away and inactive. Cats don’t hibernate or experience torpor, but some sleep more when it’s cold or rainy. Sick cats will also usually sleep more, so any sudden changes in your cat’s activity or lethargy require a check by your vet.
How Much Time Do Cats Spend Sleeping?
Cats spend much of their time sleeping, and the average adult cat can spend between 12 and 16 hours zonked out during a 24-hour period. However, much of that time is spent enjoying short naps, during which cats generally remain somewhat alert. It can sometimes seem as if cats are always sleeping since they’re active around dusk and in the early morning hours when their activity can easily go unobserved.
Why Do Cats Sleep So Much?
Cats are predators that rely on stealth and sudden bursts of energy to catch scurrying critters like mice. All the running, jumping, and pouncing cats normally do in the wild require lots of energy, leading them to engage in energy conservation (otherwise known as napping).
Cats in the wild have similar sleeping habits; African lions spend large amounts of time resting and sleeping. Kittens and older cats need more sleep, and cats sometimes start napping more when stressed, bored, or not feeling well. Health conditions such as kidney disease and arthritis can also prompt cats to spend more time sleeping.
What Is Hibernation?
Hibernation is a regulated state in which animals essentially slow down their metabolism and reduce their body temperature to allow them to survive periods when food is scarce or the outside temperature is too unfavorable and migration is not an option. Instead of spending energy trying to find food that’s not abundant during cold months, hibernating species drastically decrease their energy levels and go through periods of inactivity until spring arrives, bringing more opportunities to eat. They use fat consumed before winter to survive the period of hibernation. They may also wake up periodically to eat and drink.
Hibernation allows animals to conserve energy, but it also makes them incredibly easy for predators to catch if their resting spots are found, but some information suggests they may be less likely to be discovered as they’re not scurrying about and making noise. Hibernating animals can also die from exposure to extreme weather, and those who don’t gain enough fat beforehand sometimes don’t survive the winter. Most don’t stay inactive for the entire period and will wake up occasionally.
Torpor is a short period of involuntary inactivity that lasts only a few hours per day and is characterized by less-pronounced changes in the metabolic rate and body temperature in comparison to hibernation.1 Hibernation classes as a prolonged and more profound form of torpor.
Some animals in hot climates may do the same thing when it becomes extremely hot or water sources become scarce. Others regularly enter torpor for short periods during the day to conserve energy. Hibernators have winter rests, the duration of which may depend on the weather conditions.
What Animals Typically Hibernate?
Hibernation is common in small mammals such as chipmunks, hedgehogs, and European hamsters. Small mammals generally have more difficulty staying warm when temperatures drop than larger ones. Some types of bats, reptiles, and insects also hunker down for deep sleep, but in reptiles, this is a process called brumation. Brumating reptiles will stir occasionally to drink water but may not eat for several weeks or even months.2
Bears
Bears can hibernate for several months during winter, depending on the weather. They will not necessarily sleep this whole time, but they don’t need to eat or drink and will only sometimes urinate or defecate. They will not leave their den unless it’s destroyed for any reason.3
Bears use the urea created during cell metabolism to build protein to maintain their muscles instead of waking to go to the bathroom.4 Some even emerge from hibernation with more lean muscle than at the beginning of the winter, but most end up dropping body weight.
Bears wake from hibernation when disturbed relatively easily, which may have to do with the fact that they maintain relatively high body temperatures, unlike true hibernators like the ground squirrel and hedgehog. Bears’ bones even stay strong despite extremely long periods of inactivity, and they occasionally change posture in order to keep comfortable.
North American Wood Frogs
North American wood frogs gradually increase the amount of glucose in their cells until they become virtually freeze-proof. They spend the winter frozen in leafy nests built near ponds. It takes them about a day to dethaw!
Cod, Lemurs, and Hummingbirds
Antarctic cod can further lower their metabolism during winter in a dormant state that resembles hibernation. Dwarf lemurs in Madagascar can go several minutes without taking a breath when hibernating, with as little as six heartbeats per minute. Hummingbirds can lower their body temperatures and enter torpor to survive in close-to-freezing temperatures.
Dormice
Dormice may be some of the most famous members of the club. The tiny rodents can double their weight before hibernation, which can last several months! Dormice were an Ancient Roman delicacy, and they were fattened in special jars and served stuffed with pork.
Conclusion
Cats don’t hibernate or enter torpor over the winter, but some like to sleep more on cold, rainy days, which is quite an accomplishment since healthy cats can sleep for most of the day, even when the sun is shining. Several animals hibernate, though, including chipmunks, hedgehogs, and ground squirrels.
Hibernation is essentially an energy-saving strategy. Instead of spending energy looking for food they’re not likely to find or struggling to stay warm in challenging conditions, hibernators slow down their metabolism and body temperature, hide out somewhere safe, and wait for the conditions to change.
If your cat is spending a great deal sleeping during the winter months, this may be normal, but it can also indicate an underlying illness and is best if it’s checked out by your vet.
Featured Image Credit: Irina Kozorog, Shutterstock
