Owl Prowl: Great Horned Owls

Closeup of Great Horned Owl
Closeup of Great Horned Owl

My Thoughts Turn to Owls

Great Horned Owls live year round in Pennsylvania, but I look for them as winter temperatures chill the air and my bones. I guess it’s because of the abundance of feathers that insulate the owls from the chilly winter air. When I think of birds in winter, owls are some of the first to come to my mind.

Philadelphia Owls: A List of Species

January is also Great Horned Owl mating season. Here is my nature journal entry for my very first owl prowl.

trees_white pines_owl habitat
These white pines are prime owl habitat.

My First Owl Prowl

Donna’s Nature Journal, January 31, 2012

We held our heads back and scanned the high tree branches for the barrel  shapes of Great Horned Owls. We stood and listened.

This was my first owl prowl, a group of people walking single-file through the woods after dark, looking and listening for owls. We were about twenty people, both children and adults, with a fascination for owls. The “owl-powlers” met in the workshop before we entered the pine groove.

Eastern Screech-Owl Megascops asio) - red morph
Loki the Eastern Screech-Owl (Megascops asio) – red morph

In the center we met two educator owls who live at the rehab center, Loki, an Eastern Screech Owl (Megascops asio) and Jackson, a Great Horned Owl (Bubo virginianus). We were given a crash course on owl anatomy , vocalizations, and eating habits.

The owls that live in the Schuylkill Center were healed at the rehabilitation center and could not be released into freedom. With their damaged wings and they could not hunt.

the dense canopy of White Pine conifers

The pine woods is a nesting and roosting site for Great-Horneds. The bare branches of delicious trees can’t camouflage a Great Horned Owl. The large owl would stick out and warn potential prey. But the dense covered branches of conifers are perfect for hiding, waiting, and watching.

As the dark fell all around us. White streaks of owl droppings marked the tree trunks and alerted us to where a Great Horned has roosted and defecated. We shined flashlights in the thick pine needles beneath the trees.  We knew to look for owl pellets at the base of stained trees.

birds owl pellet
Sterilized owl pellet

A quiet and patience little girl found our first owl pellet. It was large and dark. The larger the owl, the bigger the pellets, she found a pellet large enough to be from a Great Horned Owl. Pellets are masses of the undistinguishable bits of the owls last meal.

With the finding of the owl pellets, we knew Great Horned Owls roosted in the pine grove. We stopped to listen for the distinct call of the big birds.

In the environmental center, we dissected an owl pellet before we ventured into the dark. My pellet contained the remains of a mouse. An owl can’t eat again until the pellet of the last meal is regurgitated, usually seven hours later.

dissected owl pellet
dissected owl pellet


mouse skull from dissected owl pellet
mouse skull from dissected owl pellet


January is Mating Season

For Great Horned Owls, January is mating season. Even though Great Horned Owls, stay with the same mate year after year, they still court each January.

After a late January-early February mating, the female will lay two or three, white golf-ball round eggs in the abandoned nest of a hawk, crow, heron, tree cavity or hollow stump. They are the earliest nesters of all owls.

Well Hidden in the Dark

We heard the soft courting calls of the Great Horned Owl, but we didn’t see them. They were so well hidden in the dark.

It was getting late and we walked out of the grove.  As we walked along the dark path, a shadowy figure swooped down into the undergrowth, a distance away on our right. We saw shadows and heard owl calls in the distance. The dark descent moon had not risen in the sky yet. And the group of “owl-prowlers”, big and small walked single file back through the woods.

More Information

Birds of Prey of Philadelphia, Pennsylvania, and New Jersey: A Checklist

What Do Raptors (Birds of Prey) Eat?

Identifying Birds of Prey: Books to Help You


  1. Thank-you for the beautiful post Donna. We have great horned owls that nest in a park in my dense suburban neighborhood in Eastern Massachusetts. Last year the mating pair sat in a tree in my yard calling to one another. The whole community was thrilled when they hatched two chicks in a location visible from the walking path and people came to watch them grow learn to fly and begin to fledge and practice hunting – then the Female and the two owlets were all found dead due to internal bleeding from rat poison. The exterminators who put out these hemorrhagic poisons in bait boxes claim they are bird and pet safe, but they are not. The poisons take a while to kill the rodents and the slowed down creatures become easier prey for a harried mother owl trying to feed her owlets, or for pets allowed outside. There are alternatives to poison and everyone should be aware that there are no safe rat poisons, they will kill pets and raptors. Raptors, such as beautiful Great Horned Owls, are much more effective at rodent control.

    • Hi Laura, Thanks for you comments. The story of the Owl family is heartbreaking. Thanks for reminding us, owls are more effective at rodent control that the poisons humans create. 🙁

  2. This looks like it was a really fun evening, Donna! Too cool. Jackson’s a real beauty. 🙂

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