Book Review: What an Owl Knows–The New Science of the World’s Most Enigmatic Birds

written by Jennifer Ackerman
review by JoAnn Hackos

Owls appear in cave paintings from 30,000 years ago. Harry Potter has an owl that delivers mail. Owls are considered omens—of both good and deadly. We have a Colorado researcher, Dr. Brian Linkhart, who is an expert on Flammulated Owls. Evergreen Audubon members have gone on owl searches with him, helping to band the tiny fledglings.

book cover

In her latest book, Jennifer Ackerman explores the world’s owls, which exist on every continent except Antarctica. She tells us what science has recently learned about these enigmatic creatures. And she gives the history of owls according to humans who have both feared them as demons and worshipped them as gods for millennia.

Ackerman refers to owls as “the wolves of the sky.” They are incredibly deadly killers, as she describes in the account of Australia’s Powerful Owl, an owl I’ve seen in downtown Sydney. We learn that owls are “all ears,” enabling them to pinpoint prey in absolute darkness under feet of snow, as the Great Gray Owl does. I took this photo (below) in Alaska of a female near her nest. I’ve learned now that owls like the Great Gray can “see” visual images coming through their ears.

Owls have more feathers than any other birds, enabling them to fly in nearly complete silence, below the threshold of human hearing.

Ackerman introduces us to the scientists that make the study of owls their focus. Some study how owl feathers reduce noise to support extraordinary quiet flight. Others try to understand how their ears work to direct minute sounds to their brains. They try to learn how owls locate voles under 18 inches of snow. Ackerman introduces to all the complex ways that owls use their hoots to communicate with one another. She describes the difficulties researchers have in finding owls, especially when they must search in the dark. She explains how they defend their nests and raise the owlets to independence. Through many of the accounts, we follow the adventures of Denver Holt, who is a leading owl researcher and leads trips to find owls in the northern states.  It’s all really fascinating.

I’ve seen Long-eared Owls roosting together at Chico Basin in Colorado, but I was surprised to learn of Long-eared Owl roosts in Serbia with hundreds of owls. They chose small villages where they can congregate and stay warm and away from predators in an urban setting. We learn that Northern Saw-Whet Owls may be the most common owl in North America, something no one knew before the banding projects began. They’re just so secretive.  I didn’t know that the tiny Flammulated Owls we have in Colorado migrate huge distances, as much as 180 miles a day, so that they can find the insects they need to survive as they move south.

owl
photo by JoAnn Hackos

We learn from Ackerman about how owls mate and raise their young, how they migrate, and how very difficult it is for researchers to find them in the woods in the dark. She explains the challenge of rehabilitating injured owls, especially when they frequently attack their handlers. She does include some stories of pet owls, something she does not seem to recommend. In the Afterword, she explains that considering the immense decline in the world’s species of birds, some owls seem to be doing well. Barred Owls, Ural Owls, and Eastern Screech Owls are expanding their ranges. Little Owls, Northern Saw-when Owls, and Great Horned Owls are holding their own. But owls that need big old-growth forests and open grasslands are in trouble. The most likely to become extinct are owls that exist only on islands. Snowy Owls may also be in serious decline.

To monitor owls, the researchers recommend “owl prowls” by citizen searchers, out after dark to listen and look. We might want to consider an owl prowl in Evergreen. We also might want to question some of the forest mitigation actions being taken in our area open space parks. I’m afraid that we’re cutting down the very trees that owls need to thrive.

Please read and enjoy What an Owl Knows, especially the amazing photos of so many different owls around the world. And help to preserve them.