An interesting nonfiction picture book that shows the importance of whales to a healthy ecosystem. Mason’s author note contains a reference to research papers that back up her hypothesis . The writing is illustrative and engaging. Did you know that a blue whale’s tongue is “heavy as two hippos”? In addition to a table of contents and sidebars, the back matter contains a glossary (bolded words in the text), index, and resources that tell readers how to help whales and where to find more online information about them.

The book starts by explaining whales’ feeding and pooping habits (poop plays a big part in the whales’ ecological engineering – spoiler alert!) and then outline various aspects of the environment (such as carbon and its affect on global warming). Mason then explains in clear detail with supporting illustrations and diagrams how whales’ habits positively impact the ecosystem.

The illustrations are realistic but at times, less helpful than they could be. For example, there is a “Know your Whales” diagram, showing several species of whales, beginning with blue whales, with a diver drawn to scale next to it. However, the other whales aren’t drawn to the same scale, which is confusing. It also discusses a history of whales being over hunted but doesn’t cover current controversies about whales and fishing vessels.

This would be a good addition to books on the ecosystem and offers some information on whales.

Reviewed by Deanna Contrino, Young School Library, Saco