Talking Nature: Nesting time for great horned owls

By Ron Taube
Contributing Writer

Over the last few weeks I have seen several nests for great horned owls in the Twin Cities area and heard of several others.

From early January on in the Upper Midwest, great horned owls build their nests. The truth of the matter is, however, that great horned owls don’t actually build nests. They usually take some other nest for their own. I have seen great horned owls nesting at the Coon Rapids Dam at the great blue heron rookery in one of their nests. I have seen great horned owls take squirrels’ nests. A couple of years ago at Silverwood Park in St. Anthony, a female great horned owl was nesting in a box that was built for a barred owl. They can also take hawk or crow nests.

Last year out at Lake Hiawatha in South Minneapolis a great horned owl nest fell out of a tree and someone rebuilt it and put it back up in the tree. The chicks and mom had no trouble adapting to the nest that looked a bit like a small raft held together by white and black plastic ties and attached to the tree with yellow rope.

One reason why the great horned owl may nest so early is so that the babies have time to grow and learn to hunt before the next winter. They typically choose a tree and nest in a crook of two or more branches 20 to 60 feet off of the ground. Their nests can be very hard to find, since they are high and there can be obstructions blocking your view of them. Nevertheless, than can be found by someone taking the time and with a good pair of binoculars. I can’t say for certain, but I would say that most parks of more than a few acres in the Greater Twin Cities area probably have one or more great horned owl nests in them.

An adult male great horned owl watching his nest. Photo by Ron Taube
An adult male great horned owl watching his nest. Photo by Ron Taube

Another thing that is common is that when someone finds an owl nest, most of the time they don’t report its location. It will do no real harm to the owls if one or two people watch it, but when it is reported in the media, sometimes hundreds of people will come to the nest, and that can be distracting to the nesting process. A good example of this is the Silverwood great horned owl nest that I mentioned earlier. They had so many visitors that the area had to be roped off and photographers were warned not to get too close.

If you do find a nest, though you will very much enjoy watching the young owls grow to maturity. The mom sits on eggs, usually two or three, from 28-35 days. After hatching, the young eventually work their way out onto branches within the first five weeks At this point they start flapping their wings and begin to fly in nine to 10 weeks.

Great horned owls eat rats, mice, rabbits, squirrels and even some birds as large as geese and ducks and even some of the smaller owls. They even occasionally eat snakes, lizards, frogs and a few insects. Both parents take turns feeding the young, and I have noticed that while the female is on the nest, the male is often resting within a few hundred yards of her and the nest and is always keeping an eye on it.

A great horned owl can live from five to 15 years in the wild. Its body is 18 to 25 inches long and its wingspan can be from 3.3 to 4.8 feet long. They weigh 2 to 5 pounds, and the male is smaller than the female.

You can read more on these magnificent creatures at the following links: http://animals.nationalgeographic.com/animals/birds/great-horned-owl and www.audubon.org/field-guide/bird/great-horned-owl.

Happy birding!