Nilla, the Sleeping Beauty: Resident Black Bear Prepares for the Winter
Published November 5, 2021
Article by: Tinsley Merriman, Wonders of Wildlife Marketing Intern
Winters in Missouri can be unBEARable. With the sun setting earlier and the temperature dropping lower, a lot of us are thankful for our cozy beds and blankets to snuggle into. Maybe it’s a mammal thing, as the same can be said for a majority of animals during colder months, like our resident black bear, Nilla! While humans may just hit the snooze button once or twice, our furry friend settles in for month-long slumbers to get through the winter months. If you’re thinking this is called ‘hibernation’, it’s hiberNOT! Let us explain.
From black to brown, Kodiak to grizzly, bears have widely been believed to hibernate during the colder months. The growling snores heard from these animals, however, are a different sort of hibernation called “torpor.” The main difference between hibernation and torpor is the type of sleep the animal goes into. Hibernation is a much deeper sleep, reserved for times when food is scarce and the best option is to just sleep through extreme temperatures. In torpor, a bear is still able to wake up, forage for food and even give birth, before going back to bed. Since they need to be able to wake up frequently, bears only lower their internal temperatures a few degrees, as opposed to the almost hypothermic temperatures in hibernating animals.
Snacking Before Her Slumber
Due to the recent colder weather here in Missouri, Nilla has been preparing for her own energy conserving slumber. According to Josh Harmon, one of the lead keepers here at WOW, Nilla has been living comfortably and getting her calories in the past few months. She often gets up for breakfast in the late morning, and is offered a portion of the meal in the back. The rest is then scattered throughout the yard. This allows her to forage like she would in the wild. Her favorite food is fruit, especially oranges, but Josh makes sure she gets her vegetables and protein in as well because her calorie intake is crucial during this preparation time.
When preparing to enter torpor, bears consume enough food to almost double their weight! During torpor, bears use these added pounds for energy to be able to make it over 100 days without eating or drinking. Last year, Nilla remained in her den for two months straight without getting up to eat! She only got up on relatively nice days to fluff her bed. Once the temperatures get warmer, Nilla will find that her torpor weight is gone, plus an additional 30% of her regular weight.
This American black bear is expected to begin her seasonal snooze starting in December, so next time the temperatures are low, and you’re peering through the glass in Lower Swamp hoping to say hi, think of torpor and wish a bear-y good nap to this amazing energy conserving creature!