________________ CM . . . . Volume XII Number 9 . . . . January 6, 2006


Animals Hibernating: How Animals Survive Extreme Conditions. (Animal Behaviour Series).

Pamela Hickman. Illustrated by Pat Stephens.
Toronto, ON: Kids Can Press, 2005.
40 pp., pbk. & cl., $6.95 (pbk.), $14.95 (cl.).
ISBN 1-55337-663-3 (pbk.), ISBN 1-55337-662-5 (cl.).

Subject Heading:
Hibernation-Juvenile literature.

Grades 2-6 / Ages 7-11.

Review by Patricia Fay.

**** /4


Wood frogs bury themselves in the ground in the fall. As the temperature drops, the frogs gradually freeze, beginning with their hind legs and ending with their vital organs: their heart and brain.

Why doesn't freezing kill them? Their liver produces a special type of sugar called glucose. Acting like natural antifreeze, the glucose travels through their bodies in their blood and prevents long-term damage to their cells.

Painted turtle hatchlings, or babies, can survive temperatures as low as -4°C (25°F). Over half of their body water turns to ice, their heart stops and their blood stops flowing. They can live like this for up to five months!



Pamela Hickman explains that hibernators are divided into two groups. True hibernators, such as chipmunks, insects, toads and snakes, lower their body temperatures and partly freeze their bodies. On the other hand, deep sleepers, such as skunks, raccoons and bears, only lower their body temperature slightly and may wake up on any mild day.

     This fascinating book is also filled with interesting facts like these: Water-holding frogs live most of the year buried in an underground burrow; the Arctic ground squirrel is the only known mammal that can survive dropping its body temperature to -2°C to -3°C, whereas people cannot survive a body temperature lower than +32°C.

     When we think of hibernation, we think of cold climates, but some desert animals also seek shelter and become inactive for long periods of time to avoid high heat and drought conditions. This is called "aestivation."

     There are three simple experiments that the reader can try. Each experiment has easy-to-follow, step-by-step directions that explain heart rate, why true hibernators' blood does not freeze, and why animals curl up when they hibernate.

     Some of the pages have a sidebar titled, "If you were a ..." that gives short, bullet facts about a specific animal.

     The illustrations by Pat Stephens are beautifully drawn; the page with the sleepy black bear is stunning! The book has a table of contents, an index and a glossary. It would be a useful addition to any library and perfect for a unit on how animals prepare for winter.

Highly Recommended.

Patricia Fay is a teacher-librarian at Beaumont Elementary School in Winnipeg, MB.

To comment on this title or this review, send mail to cm@umanitoba.ca.

Copyright the Manitoba Library Association. Reproduction for personal use is permitted only if this copyright notice is maintained. Any other reproduction is prohibited without permission.
Published by
The Manitoba Library Association
ISSN 1201-9364
Hosted by the University of Manitoba.