Great Horned Owls — Family Portraits

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Today, more portraits of Great Horned Owls. My friend Dan, who seems to know where every nesting pair of Great Horned Owls in the Tucson metropolitan area is located, invited me one evening a couple of weeks ago to capture images of a family. The owls had established their home in a suburban community on Tucson’s far west side.

I’ve posted fairly often about Great Horned Owls. These big predators live all over North America and are by no means rare. Indeed, I wouldn’t be surprised if there are many communities with populations of Great Horned Owls that are as dense as they are in Tucson. What I find to be fascinating about these owls is that, as common as they are, people seldom see them. That’s due to these birds’ lifestyle, of course, but due equally to ours. Not to oversimplify it, but Great Horned Owls work the night shift, being primarily nocturnal. Humans are primarily diurnal. So the owls are active when we’re asleep and vice versa.

This family had chosen to set up housekeeping in the arms of a Saguaro cactus, where they raised three offspring. Great Horned Owls don’t build nests. They’ll appropriate nests built by other species — Red-tailed Hawks and Cooper’s Hawks’ nests being preferred choices in our community — but they’ll also lay their eggs and raise their families in a wide range of sheltered areas. I’ve seen them nesting in the crowns of palm trees, and amid the arms of Saguaros. A few years back an owl laid her eggs on a light pole in a Walmart parking lot in Tucson.

When Dan and I arrived at this family’s domicile we discovered that two of the offspring had fledged and were no longer on the cactus. A third youngster, just shy of fledging, remained.

We learned that this owlet left the cactus later on that same evening.

Adult Great Horned Owls will continue to watch over and feed their young well after the kids leave the nest site. On this evening, both parents were ensconced in a big Mesquite tree across the street from the nest cactus. Here’s the male.

And here’s the female.

The family’s two other offspring were perched in the mesquite with their parents, buried in foliage and not photographable for that reason.

You might be wondering how I can discern which of the adult birds is male and which is female. It’s not plumage color differences — although this female is distinctly browner than her mate. Great Horned Owls display color variation among individuals, with some birds being grayer in color, others being more brown. But those differences aren’t gender-related.

Notice the vertical line running down the female’s breast? That’s her “brood patch,” an area of plumage where the feathers aren’t as densely packed as elsewhere on her body. Incubating birds will often shed plumage on their breasts, an evolved way of allowing their warm skin to remain in contact with eggs. The female will lose her brood patch with her next molt.

This family is not the last Great Horned Owl family that I photographed this year. There is another, and I will be posting images of that family soon.

Images made with a Canon R5, Canon EF 400mm f4 DO II lens, M setting (auto ISO). All images, f5.6 @ 1/1600. First image, ISO 800, +2/3 stop exposure compensation. Second image, ISO 5000, +1 1/3 stops exposure compensation. Third image, ISO 2500, +2/3 stop exposure compensation.