Preparing for the winter takes many forms in the animal kingdom. One that fascinates young and old is hibernation, and bears quickly come to mind for this concept. There are many other hibernators, though, including other mammals, snakes, bugs, bats, and amphibians! Share a program with families during the darkest part of the winter to explore this phenomenon. Inviting the kids to come in PJs might make it even more fun, or if the weather permits, invite those attending to dress for an outdoor excursion to search for hibernating bugs and small critters under rocks and leaves outside! (Just don’t forget to let sleeping critters lie!)
As always, I begin with some good books… titles I like include Why Do Bears Sleep All Winter? by Englar; Bear Has a Story to Tell, by Stead; Sleep, Black Bear, Sleep, by Yolen, which includes many other animals that hibernate as well; and Time to Sleep, by Fleming, which also includes other hibernators. General discussion of adaptations can be included, as well as discussion about what makes hibernation an adaptation.
Asking attendees to imagine sleeping for weeks without waking up and eating each day is a good way to prompt discussion of the preparations animals make for hibernation. This in turn can lead to the concept of storing food and increasing their fat layer for insulation. This idea can be studied in a literal hands-on way with the following experiment adapted from here:
- tub of ice water
- gallon-sized plastic bag filled with petroleum jelly or cooking shortening such as Crisco
- gallon-sized plastic bag filled with dried leaves (or cotton balls or torn pieces of paper)
- gallon-sized plastic bag filled with cut pieces of yarn or a piece of fake fur
- smaller plastic bags
What to do:
Explain that each bag represents an adaptation which may be used by animals to survive the cold during hibernation. The jelly or shortening represents an extra layer of fat or blubber; the leaves (or cotton balls or paper) represent natural materials that may be used to fill a den space; the pieces of yarn or fake fur represent thicker, longer winter fur. Place a smaller plastic bag in the middle of each of the three filled gallon-sized bags, so that students are able to put their hands inside the inner bag, creating “mittens” of each type of insulation. Set the bags open-end up into the tub of ice water. Have the students compare how cold the hand inside each insulted bag feels relative to a bare hand dunked in the ice water. Ask the students which insulation form keeps the hand the warmest: blubber, dry leaves and other filler materials, or extra fur. Why do they think this is true? What do they think would happen if more than one form of insulation was used, like extra fat and a den filled with dry leaves?
A number of different websites offer hibernation and winter preparation activities and lessons, many with some form of this experiment. A few that also include book lists and other related topics are:
http://www.cpalms.org/Public/PreviewResourceLesson/Preview/30405 (includes discussion of migration)
A natural extension of this lesson would involve the adaptation of different types of bears, and how each is uniquely suited to its own environment. This could lead directly to another lesson on habitats. The Project WILD activity called What Bear Goes Where? would be an excellent way to continue the concept. An adaptation of that lesson can be found here: https://www.michigan.gov/documents/dnr/WLD_What_Bear_Goes_Where_MI_Adaptation_338962_7.pdf
Zunal.com offers a WebQuest related to this bear activity as well,
which can be accessed here: http://zunal.com/webquest.php?w=275609
A book kit for younger students, based on the book A Bear’s Year, is available here: http://www.curiouscitydpw.com/2015/11/15/a-bears-year-read-aloud-kit/