K-Gr 2 This attractive picture book portrays the relationship between wolves and ravens, explaining how these birds often lead wolves to prey that both creatures can then eat. Having lost the chase of an evasive bison, the cold, wandering wolves follow a familiar cry, "the sound of hungry ravens!" Working together, wolves and "wolf-birds" track and hunt prey to keep starvation at bay during the long, northern winter. Readers meet ravens huddling in the snowy trees, gliding through treetops, "filling bellies and beaks." Wolves are presented not only hunting but playing, stretching, and "trundling over a snowy hill, down to a warm den." Graphic novelist Dawson's acrylic-on-cardboard illustrations suggest an archetypal, cave painting style, at times whimsical but nonetheless dynamic and intimate. Muted, earthy colors reflect the winter season. An author's note at the end of the book explains the relationship between ravens and wolves in the context of ecological mutualism. Despite the straightforward treatment of the "cycle of life," some sensitive readers may find elements of the story disturbing. Wolves chase down a hungry and injured deer, and "one animal's life helps many others live." A few illustrations depict wolves and ravens carrying away bones and chunks of flesh. Sources are amply documented on the copyright page. A full bibliography and list of recommended books is available on the publisher's website. VERDICT A stellar introduction to forest ecology.— Bob Hassett, Luther Jackson Middle School, Falls Church, VA

Wolves and ravens work together (an author's note explains "mutualism") when the birds alert the pack to an injured deer. The ravens and the pack pursue the creature, then feast and share the bounty with their families. Earth-toned acrylic paintings, with stylized, flat forms, avoid graphic detail, focusing instead on the creatures' survival. Matter-of-fact language describes the hunt and feast. Bib.