exploring northwoods nature through science and your senses
Monday, March 24, 2014
“Who’s awake? Me,
too...” I love to hear the deep, powerful hoots of a great horned owl billowing
through a snowy forest. Their stuttering rhythm -- hoo-h’HOO-hoo-hoo – seems to
ask the question, then offers a conspiratorial answer.
I usually hear great horned owls in early winter, as they
form pair-bonds and defend territories in preparation for nesting season. These
large owls don't build their own nests, but take over nests made by crows,
squirrels, hawks, or herons--whether their previous owners were ready to move
out or not.
In late January and February things quiet down as the
larger female owl lays from one to four, but most often two, eggs. She must
begin to brood immediately, and then for the full 35 day incubation period, so
that the eggs don’t freeze. Because of the necessity of constant brooding,
great horned owls have a very strong pair-pond, and the attentive male brings
food for the female, and eventually the chicks.
Why must owls nest in the depths of winter? It takes a
long time for the owlets to grow up, and they require parental care well into
July. If the owls waited until June, like the smaller birds, the young owls
would not be strong enough before the next winter.
Just thinking of a 3 ½ pound owl, right now, sitting in a
snow-covered nest with eggs or young chicks, makes me feel cold. But the owls
Excellent eyesight, precise hearing, and silent flight
make great horned owls intimidating nocturnal predators. Their super strong
talons (reported to crush prey with a force somewhere between 30 and 300 pounds
per square inch) allow them to hunt such formidable prey as porcupines, geese,
and scorpions. Speaking of tough, they are the only regular avian predator of
From their place at the top of the food chain, the only
things great horned owls have to worry about are territorial disputes with each
other, eagles, and snowy owls. Oh, and those pesky crows. Great horned owls are
crows’ most dangerous predators, but if crows find an owl during the day, they
will flock to it and harass it with the safety of numbers. One author
hypothesizes that the long hours of darkness during their breeding season helps
to protect the owls from crow harassment.
As tough as they are, owls do have one more predator to
worry about – humans and our vehicles. Road ditches – where trees for perching
meet grass with small rodents – are tempting places for owls to hunt. When you
throw your apple core out the window, it attracts even more rodents, which
lure even more owls. Unfortunately, when
an owl is focused on its prey, it won’t notice your headlights closing in.
Most of the Museum’s collection of owl specimens were
picked up on the side of the road. Their wings and feet make great educational
tools, but we’d much rather have live birds in the wild.
Not every car-owl collision ends in the salvage freezer,
Last summer, Joe Papp, a Museum volunteer who has
experience with raptors, noticed a great horned owl in the ditch along Highway
63, just south of Drummond, several days in a row. When Joe was finally able to
catch the owl, it was obvious that its wing was injured, and the owl couldn't
Well, Joe brought the owl to Katie Connolly, our Museum
Naturalist/Curator, and she delivered the owl into capable hands at the Raptor
Education Group, Inc., in Antigo, WI, where they have licensed rehabilitators.
“Unfortunately his wing had been broken at a joint, and
had already begun to heal, leaving him crippled and unable to fly ever again,”
Katie told me. “The rehabilitators believe he was struck by a car on Highway 63
and began eking out a living next to the roadside because he couldn't fly away.
We can only imagine him running down mice and other rodents to eat!” she added
with a chuckle. That’s just one more example of owl toughness.
Because the owl can’t fly, he wouldn't have a fair shot
at surviving in the wild, and is non-releasable. Six months after the accident,
the male great horned owl, now named Theo, is safe and well fed in his home in
the raptor mews at the Cable Natural History Museum. With Katie as his trainer,
Theo will soon be an education bird who can help kids of all ages learn about
the amazing adaptations, and toughness, of great horned owls.
We’ll be posting updates about Theo’s training progress,
construction of his new home in the Museum’s outdoor classroom, and public
programs where you can meet him, on our website (www.cablemuseum.org) and
While you wait to meet Theo, don’t forget to keep an
eye—and an ear—out for his wild cousins. Who likes owls? Me too.
For over 45 years, the Cable Natural History Museum has
served to connect you to the Northwoods. Come visit us in Cable, WI, at 13470
County Highway M. The current exhibit, “Deer Camp: A Natural and Cultural
History of White-tailed Deer,” opened in May 2013 and will remain open until April
Find us on the web at www.cablemuseum.org to learn more
about our exhibits and programs. Discover us on Facebook, or at our blogspot,