Friends of the Wild Flower Garden

Eloise Butler Wildflower Garden and Bird Sanctuary

Part I - Great Horned Owls in the Garden

by Rod Miller

Grat Horned Owl
Photo by Roy Larson

In the cold of winter, new life begins in the nest of Great Horned Owls right in the backyard of Eloise Butler Wildflower Garden and Bird Sanctuary. A family of owls has been observed at the Garden for many years. Many in the nearby Bryn Mawr neighborhood report hearing the owls from the Garden parking lot when walking in the woods or right outside their bedroom windows. It’s most likely you will hear the four to five hoots of the male owl “hoo-h’HOO-hoo-hoo” at dawn and dusk before you see him. A higher pitched voice with a few more syllables is the female. She’s also about 30% larger than the male. The owls are frequently heard and seen on the footpath surrounded by White Pine and Spruce trees just east of the Garden. Neighbors also report hearing owls near The Bryn Mawr Meadows, Basset Creek along Chestnut and in Wirth Woods west of Xerxes. Beginning in October the owls become more vocal, defining their territory and claiming a nest. In January you’ll hear their mating calls, called a duet.

Although I’ve been hearing and seeing the owls for years, last winter I decided to observe their courtship, mating and nesting behavior.

They are large owls named for the tufts of feathers on their head, which are neither horns nor ears. Great Horned Owls mate for life, nest, raise their young called broods and live in Minnesota year round. They rarely build their own nest but move into nests already built by other large birds, such as hawks and crows, in cavities of trees and sometimes in the nests of squirrels. While Great Horned Owls have one of the most diverse diets of all North American raptors, they mainly eat small rodents and mammals. An owl is not likely to hunt your small dogs or cats hanging out in your back yards but it has been reported.

Great Horned Owls
Photo by Nina Hale

Great Horned Owls usually lay eggs in late January or the first of February. They will hatch in about 30 days, certainly by the time you will read this article. They raise only one brood a year, usually with 2 owlets. I observed the Garden owls mating the month of January and first week of February just outside the Garden. As of February 15, it appears the owls have chosen a nest in the pines just east of the Garden. The female assumes primary responsibility for incubating the eggs while the male brings food for her and the nestlings. If all goes according to plan, hatchlings should appear around the second week of March. By the end of March, you may hear the owlets clapping their bills or shrieking, as they beg their parents for food. Around the middle of April, they will begin climbing from the nest to nearby branches. They are called “branchers” then and you can see them sitting in the sun. After developing wing feathers in early May, they become fledglings as they clumsily learn to fly from branch to branch. They will move out of the nest by mid-June and will be moving around more as they learn to fly and hunt for food.

You’ll have to search to find them. The adults care for the juveniles throughout the summer and fall, feeding them while teaching them to hunt until they reach sexual maturity in 1-2 years. The feeding territory established by the adults usually cannot support more owls so the juveniles are chased out of the territory by their parents usually in December before the next breeding season. Occasionally, one may hang around a bit longer still begging for food.

The white, speckled downy feathers on the breasts of the owlets make them easier to find than the adults. If you find an owlet, look around. An adult owl will always be nearby protecting it and more important, feeding it. If you hear the alert calls of Blue Jays or American Crows, look around. There’s a good chance they have found the owls and are harassing them. They don’t get along.

pair of owlets
Photo by Roy Larson

When you see the Great Horned Owl and their owlets, you will be mesmerized. Try not to stress them by making noise, making hooting calls, trying to make them fly or by getting too close. You might even consider watching owls and other birds as a hobby. Bird watching gets you out of the house into nature for some exercise and will give you something fun to talk about with your friends. Oh, you’ll also see some fantastic birds that otherwise go unnoticed. To learn more about birds and observe them in the Garden, considering joining Garden Naturalist Tammy Mercer on Saturday mornings for the Early Birders program from April through October. (Special thanks to Tammy who helped with this article).❖

Web references:
all about birds
international owl center

Rod Miller is a neighbor of the Garden, former volunteer, and participant in its programming.
This article was originally published in The Fringed Gentian™, Vol. 69 No.1, Spring 2021.

Part II - Historical notes on the Great-horned Owl

Comments of former Curator Ken Avery

1. 1973: One old friend that gave me a fright last year is back, however, and seems to be ready to stay — our Great Horned Owl. Last year I saw him a few times in late fall and then not one more time all winter. I was afraid the greatly expanded winter use of the area all might have but he discouraged this shy bird and that he had secured more remote lodgings, but he is back as usual this winter.

2. 1974: I also have some other owl news from last year. The Great Horned Owl has wintered in the Garden many years, more than I have been there, and we have assumed that they nested in that area — they nest in February. I had even seen two of them making overtures, but until last summer we had never seen the nest or their young. Last spring someone reported that they had seen a young owl in the wild area west of Birch Pond. We found one of the young and a few days later found a second one. They both disappeared, but then I saw one in the fall fully grown. Now I have a second-hand report of the owl nesting in the park again, but I have not seen it personally.

3. 1976: Another thing that is happening is that the Great Horned Owl is busy having a family again. This may seem like a strange time to be sitting on a clutch of eggs but it is the time that the Great Horned Owl picks. I would think it would be a little uncomfortable, and I must say when I saw her half covered with snow she didn't have a terribly happy expression on her face; but she has no one to blame but herself. This is the third year in a row that we have been aware of the owl nesting in the area. I have no way of knowing if one nested there for the last 20 years, but since we have found it for the last three years and never did before, I wonder if during those high D.D.T. years they did manage to nest or if we simply managed to miss it. You know that the eagles have been having better nesting success these last few years since the D.D.T. has become less prevalent in the environment.

Ken Avery was Curator/Gardener at Eloise Butler from 1959 through 1986. His comments were originally published in The Fringed Gentian™ during those years.

Part III - Rescue of Great-horned Owl

In 2014 an injured Great-horned Owl was found just outside the Garden fence. It was re-habilitated and then release. ARTICLE

Other birding articles on this website.