As winter approaches, Michigan’s black bears will be hunting for a suitable den. If you’re not careful, that den may end up being the cozy hideaway beneath your deck or that pile of brush out back.

BearWise, a partner of the Michigan Department of Natural Resources, notes that as the days grow shorter and food supplies dwindle, bears know it’s time to stop hunting for food around the clock and start looking for a safe place to spend the winter.

Hollow trees, caves and dense thickets all appeal to bears in search of a winter den, BearWise explains in this article. But did you know the crawl space or storm cellar you forgot to seal up, that pile of tires or brush out back or the shed full of tools can seem like a great place to turn in for the winter?

To a bear, these areas can seem like the perfect winter home. They’re dark, snug and often come with at least one built-in wall. Bears don’t have collarbones, so even adult bears can fit through what seems like an impossibly small opening – such as an average-sized pet door.

Bears may also make themselves at home in garages, storage sheds or vacation homes that are vacant over the winter.

Michigan is home to an estimated 10,300 bears in the Upper Peninsula and 2,100 bears in the Lower Peninsula.

“At this time of year and given relatively warm conditions, most bears in Michigan are likely still out and about foraging,” said Jared Duquette, human-wildlife interactions specialist with the Michigan DNR. “However, most bears typically forage and look for dens at the same time.”

Bears in some parts of the U.P. probably have a stronger mindset to look for dens given recent snowfall and colder temperatures, particularly if these conditions persist, Duquette said.

In the Lower Peninsula, the DNR is still getting nearly as many bear complaints as it did in July, particularly in the northwest part of the peninsula. “I suspect bears in the Lower Peninsula are a few weeks from denning, depending on the weather,” Duquette said.

BearWise gives plenty of practical tips on how to keep bears from moving in for the winter, including simply locking all ground floor and bear-accessible windows and doors. Bears can easily operate lever-style door handles but are stymied by round doorknobs. Extra bonus points: install doors to open out, not in.

BearWise also offers tips on how to scare bears away from your property on this fact sheet.