Ravens in WinterBook - 1989
Why should ravens--which are usually solitary birds--share valuable food in the dead of winter? How clever are these birds? Do they have a language? These are some of the riddles that noted sociobiologist Bernd Heinrich, author of Bumblebee Economics and winner of the John Burroughs Medal, explores in this intriguing book. 16 pages of drawings.
Publisher: New York : Summit Books, c1989
Characteristics: 379 p.,  p. of plates : ill. ; 23 cm