Which Animals Hibernate and Which Stay Active in Winter?

As the temperatures drop and winter rolls in, many animals have two choices: hibernate or tough it out. If you’ve ever wondered which critters are snoozing through the cold months and which are still scurrying around your property, we’ve got the answers!

Let’s break it down by species and see who hibernates, who doesn’t, and what that means for homeowners.

Birds: Always on the Move

Birds don’t hibernate. Instead, many migrate to warmer climates to avoid the winter chill. Species like geese, robins, and warblers head south, while hardy birds like chickadees and cardinals stick around, fluffing up their feathers and foraging for food. If you have a bird feeder, you might notice an increase in activity as winter residents take advantage of an easy meal.

Bats: Light Sleepers of Winter

Bats are a little trickier. Some species, like the big brown bat, hibernate in caves, attics, or other similar structures, slowing their metabolism to conserve energy. Others enter a state called torpor, which is like a light hibernation but allows them to wake up if temperatures fluctuate. If you’ve had bats in your attic before, winter might not mean they’re gone—it just means they’re sleeping!

It's important to note that bats are federally protected, and they cannot be removed while they are hibernating during the winter. Disturbing them during this time can be harmful to their survival. If you suspect bats in your home, the best course of action is to wait until the appropriate removal season. Our team at Vanguard Wildlife can perform an inspection during the winter to provide you a comprehensive plan for removal in the spring.

Learn more about when bats can be safely removed here: When Can You Remove Bats?

Squirrels: Always Active, Always Hungry

Despite the cold, squirrels do not hibernate. Squirrels are members of the rodent family and they stay busy all winter, foraging for food and using the nuts they buried in the fall. If you hear scurrying in your attic during winter, chances are a squirrel has moved in, looking for a warm place to nest.

Raccoons: Winter Opportunists

Raccoons don’t fully hibernate, but they do go into torpor during short periods of extremely cold weather. This means they sleep for long stretches but can wake up and scavenge when needed. If you have trash or pet food outside, raccoons might still be active on milder winter nights.

Beavers: Built for the Cold

Beavers stay active all winter, thanks to their food storage habits and impressive lodges. They create underwater entrances to their homes and stockpile sticks and branches to eat throughout the season. Since their dens are well-insulated, beavers don’t mind the cold and keep working through the winter.

Groundhogs: True Hibernators

Groundhogs (also known as woodchucks) are classic hibernators. As soon as temperatures drop, they burrow underground and enter a deep sleep, slowing their heart rate and body temperature dramatically. They don’t wake up until spring—unless, of course, it’s February 2nd, when Punxsutawney Phil comes out of his snooze to "predict" when spring will begin.

What is True Hibernation?

Unlike animals that enter a light sleep or torpor, true hibernators, like groundhogs, experience a drastic drop in body temperature, sometimes as low as 37°F (3°C). Their heart rate slows from about 80 beats per minute to just 5, and their breathing nearly stops. This deep state of dormancy helps them survive the winter without needing food or water.

However, hibernation isn’t a continuous sleep. Groundhogs experience periodic arousals every few days or weeks, during which their body temperature rises and their metabolism briefly increases. Scientists aren’t entirely sure why these arousals happen, but they may help maintain brain function and prevent muscle atrophy. After these brief wake-up periods, the groundhog returns to its deep sleep until spring arrives.

What Does This Mean for Homeowners?

Understanding which animals hibernate and which don’t can help you prepare for potential winter wildlife issues. If you’re hearing strange noises in your attic, walls, or under your porch, it’s probably not a hibernating groundhog—it’s more likely squirrels, raccoons, or even birds.

If you suspect unwanted guests in your home this winter, don’t wait until spring to address the problem. Contact a wildlife removal expert to safely and humanely relocate any critters that have made themselves at home.

Got a wildlife issue? Give us a call—we’re here to help, no matter the season!

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Contact Vanguard Wildlife Today!

Vanguard Wildlife’s team of NWCOA-certified wildlife control operators serve Rhode Island, Massachusetts, and Connecticut. Our professionals provide strategic, long-lasting solutions for homes and businesses. Whether you’re dealing with bats in the attic, raccoons in the chimney, or squirrels in the walls, we have the expertise to handle it all.

Don’t let winter wildlife take over your home—call Vanguard Wildlife today for professional wildlife removal services!

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