Great Horned Owls in the Sonoran Desert

By Matt Griffiths

By Rhett Herring

The Sonoran Desert is one of the world’s hotspots for owls due to its great variety of habitats. Southeast Arizona is home to 13 species of owls: Barn, Flammulated, Western Screech, Whiskered Screech, Great Horned, Northern Pygmy, Ferruginous Pygmy, Elf, Burrowing, Mexican Spotted, Long-eared, Short-eared, and Northern Saw-whet. That’s quite a few for one region!

For many people, the Great Horned Owl is the quintessential owl, the one you picture when you think "owl." Its large ear tufts, intimidating yellow-eyed stare, and solemn, deep-toned who-hoo-ho-oo calls, might transport you to the creepy forests of an old Disney cartoon! This bird is worthy of being an archetype in North America though: it’s our third largest owl (behind Snowy and Great Gray), has the widest range of nest sites and habitats of any other bird, and has the most diverse diet of all our raptors. It’s also fairly common, equally at home in deserts, wetlands, forests, grasslands, and urban areas between the Arctic and the tip of South America.

January is the perfect time to get acquainted with the Great Horned Owl as it is just kicking off its breeding season in Southeast Arizona. It’s one of the earliest breeding birds here in our desert with courtship beginning in November and December—the pair will sing a duet of hoots, with the male’s slightly lower in pitch. Peak nesting activity is late March into early May when the young birds leave the nest at about six weeks old. They won’t learn to fly for several weeks and are known as “branchlings” during this time. The cute, fluffy chicks will explore their small world right around the nest—this is a great time to view owl activity if you’re lucky to find a nest. Great Horned Owls don’t build their own nests but utilize a wide variety of existing sites such as old hawk, heron, or raven nests, tree hollows, under bridges, inside old buildings, cliff ledges, human-made platforms, and large saguaros here in the desert.

By Matthew Studebaker

Great Horned Owls are fierce perch and pounce hunters with extremely large eyes (even for an owl), powerful talons, a large facial disc (the collection of feathers surrounding the eyes) that funnels sounds to their ears, and the ability to swivel their heads more than 180 degrees to easily track prey. They have been known to take down small mammals and birds larger than themselves (including Osprey, Peregrine Falcon, herons, and other owls), but they mostly feed on small rodents, reptiles, insects, fish, and even carrion. Great Horned Owls have amazing hearing that is about ten times better than humans—they can hear things up to ten miles away and close prey sounds with incredible accuracy due to their asymmetrical ears. When they do catch something, their super powerful talons hold on with a grip strength of 200 to 500 pounds per square inch! In comparison, humans average around 100 pounds per square inch. And by the way, the owls’ “horns” or ear tufts don’t have anything to do with their ability to hear but instead help with camouflage. The tufts are also called plumicorns, meaning “feather horn” in Latin.

Great Horned Owls are charismatic and well known to many people because they are fairly tolerant of human activity. This has no doubt led to an unwarranted fear among urban pet owners that the owl is a frequent predator on our cats and dogs. Great Horned Owls can typically only carry their own body weight, 2–3 pounds, so only the smallest pets are in danger. Their dive bombing of cats, dogs, and people near a nest site can be confused for a hunting attempt.

The Great Horned Owl is a unique species that is at home in many parts of the Sonoran Desert and maybe even your own neighborhood environment, especially if large pine or eucalyptus trees are present. To ensure your home is welcoming to these special creatures of the night, please do not use rodenticides. If an owl eats a contaminated rodent or comes into contact with the bait directly, they can become extremely sick and even die. Plus, having owls around acts as natural pest control!

By Rhett Herring

Step outside at dusk or dawn, and scan high perches such as phone lines, trees, and saguaros for the Great Horned Owl’s distinct outline. If you’re lucky, you’ll hear their tell-tale low hooting or see one gliding silently overhead.

Matt Griffiths is Communications Coordinator for Tucson Audubon.