For years now, the pets and animals category has followed a certain hierarchy: dogs on top, cats beneath them, and “other” animals—birds, snakes, gerbils, hamsters, horses, and assorted other furry friends—grouped a rung below.

But based on the response to PW’s call for information on books in the category and a general analysis of the market, dogs are facing a challenger these days, and it’s not from the expected quarters. Many publishers are shifting their focus from the four-footed to the two-winged. Bird books are increasing in number, and canines no longer rule the roost.

Many of these books take a naturalist or biological approach, as opposed to the memoirs that tend to dominate among dog titles. Recent works include such bird-brained books as Tim Birkhead’s Bird Sense: What It’s Like to Be a Bird (Walker & Co., Apr.) and Jon Young’s What the Robin Knows: How Birds Reveal the Secrets of the Natural World (Houghton Mifflin Harcourt, May), as well as Thor Hanson’s Feathers: The Evolution of a Natural Miracle (Basic Books, 2011).

This shift isn’t completely out of the blue, either, as the number of books on chickens in particular has been on the upswing for several years. Wiley acquisitions editor Erin Calligan Mooney sees the rising popularity of backyard (as opposed to farmyard) chickens as just one part of a larger social trend. She notes, “The domestic raising of such animals as chickens, goats, pigs, and sheep has increased because of popular trends such as sustainable lifestyle choices and predilections for organic food products. These DIYers want and need resources to keep their flocks and herds happy and healthy.” In February 2013, Wiley’s For Dummies imprint will publish Chicken Health for Dummies by Julie Lyn Gauthier and Robert T. Ludlow, an $18.99 guide to keeping the flock in peak condition that includes chapters on diseases caused by parasites, general prevention in the form of “biosecurity,” and which diseases can and cannot be transmitted from chickens to humans.

Chickens are also the focus of Lauren Scheuer’s Once upon a Flock: My Life with Some Soulful Chickens, coming from the Free Press in March. And in February, the Free Press will publish Gifts of the Crow: How Perception, Emotion, and Thought Allow Smart Birds to Behave Like Humans by John Marzluff and Tony Angell in paperback. Marzluff posted a video of a crow sledding down a roof in Russia in early 2012, and the video went viral, earning 700,000 viewers around the world. He followed up on that popular video with this explanation of the intelligence of birds in the crow family and explanations of why and how they “surf,” use tools, and retrieve food from hidden places.

Nondomesticated birds are the subject of bird-watching guides. In March of 2013, Little, Brown will publish The New Stokes Field Guide to Birds: Eastern Region and The New Stokes Field Guide to Birds: Western Region, a pair of trade paperbacks by Donald and Lillian Stokes. The guides cover hundreds of North American species and contain more than 2,000 color photographs.

That’s not to say that dogs are unpopular or have ceased to inspire books. After all, birds may be increasingly popular, but they’re present in only 5.7 million American households, compared to the 46.3 million households that have at least one dog and the 38.9 million households that have at least one cat, according to the 2011–2012 statistics of the American Pet Products Association. Indeed, eight out of the top 10 biggest sellers on Amazon’s animal and pet care list as of this writing are about dogs (though in the interest of the avian world, it bears noting that the top-selling book is the Kindle edition of Bob Tarte’s Enslaved by Ducks, first published by Algonquin in 2003).

Even before HarperCollins published John Grogan’s Marley and Me in 2005 and saw it explode (according to BookScan, the book has sold more than three million copies in various formats, not to mention the many Marley offshoots), publishers were trying to get a piece of the puppy-loving audience. Harlequin Nonfiction senior editor Sarah Pelz says, “Every year there’s at least one breakout dog book, whether it’s narrative or humor. Pet books in general are a strong, stable category for us and the dog books in particular resonate with our readers. Editorially, we look for well-told, heartfelt stories. And it never hurts to put an adorable dog on the cover.”

Harlequin Nonfiction has two entries in the dog category: A Dog Named Boo: How One Dog and One Woman Rescued Each Other—and the Lives They Transformed Along the Way goes on sale at the end of this month. In this memoir, certified professional dog trainer Lisa J. Edwards chronicles Boo’s journey from abandoned runt of the litter to therapy dog, and her own healing from abuse and chronic medical problems. Last month, Harlequin published The Dog with the Old Soul, edited by Jennifer Basye Sander, an anthology of stories about how dogs and other animals have had an impact on human lives.

This month Barron’s published Kim Kavin’s Little Boy Blue: A Puppy’s Rescue from Death Row and His Owner’s Journey for Truth. After adopting a brindle puppy from an animal shelter in North Carolina, Kavin became curious about his past and traced the dog’s journey through the shelter system. The title takes a hard look at what goes on in animal shelters and also explores the growing network of volunteers struggling to save thousands of animals.

And with dogs so popular, it’s natural that the people who love them are curious about how their minds work. Recent years have seen a rash of psychology books about dogs, such as Dog Sense: How the New Science of Dog Behavior Can Make You a Better Friend to Your Pet by John Bradshaw (Basic Books, 2011) and Your Dog Is Your Mirror by Kevin Behan (New World Library, 2011)

For its part, in February, Dutton will publish The Genius of Dogs: How Dogs Are Smarter Than You Think by cognitive scientists Brian Hare and Vanessa Woods. Dutton executive editor Stephen Morrow says, “When it comes to domesticated animals, people are really curious about what is going on in their heads—especially dogs. Modern cognitive science has generated a trend in the kind of books available for animal lovers: we are now learning not only how we think, but how animals think. What I find most fascinating about The Genius of Dogs is how important domestication is to the intelligence of dogs. We tend to believe wild animals are cunning and our pets are, well, a bit soft. Basically, Hare’s research shows that dogs domesticated themselves by developing a social intelligence that has made them the second most successful mammal on the planet.”

Diving Dogs

There’s no shortage of books (and calendars and other items) containing photographs of dogs, but Seth Casteel’s Underwater Dogs, an October hardcover from Little, Brown, may be unique. The 80 portraits capture canines underwater looking almost eerie.

The popularity of these photographs by Casteel, a professional lifestyle pet photographer, is a viral success story. In February 2012, the Facebook page for Casteel’s company, Little Friends Photo, which included some striking shots of dogs underwater, suddenly went from 9,000 fans to 46,500 fans. Casteel is still unsure why it happened.

But Little, Brown executive editor John Parsley has a good guess as to what it is that makes these unusual pet pictures so appealing. Parsley says, “We’ve seen photos of dogs in every position, of every size, and every level of cuteness, and it’s probably not surprising that it’s taken something truly otherworldly to really turn heads. Seth Casteel’s dogs are mesmerizing.”