Took a drive out to one of my favorite spots and stopped to walked the dog. I didn’t even see the bird in the tree until the dog and I had gotten back into the vehicle and I had turned around to drive away.
I have heard the owls at the cemetery since I was a kid and have seen one fly there on occasion but I have never had one sit still as a church mouse as me and a dog walked nearby and then remain to allow me to photograph it for several minutes. It might have had something to do with a large, nearby, woodpile. I am guessing supper was there. It never did fly off; I left first.
Found throughout most of North America and much of South America, is the Great Horned Owl. This owl is a permanent resident of Illinois.

This powerful bird of prey is sometimes known as the ‘tiger owl’ because of its aggressive nature. It preys on as mice, rabbits, hawks, snakes, skunks, lizards and frogs, a variety of insects but rarely fish. They make their kill with approx. 28 lbs. of pressure in the beak used to break the back or neck of its prey.
Great Horned Owls prefer habitats near forests, woodlots, streamside, and open countryside. Any place it can find cover in brush or trees is a good habitat for this large bird. They can also be found nesting in cliff walls, caves, and broken tree stumps, and sometimes, living in cities where refuge is available.

Nesting can begin as early as late winter so that there is time to find a mate and have young raised and hunting by the following winter. Many times, the Great Horned Owl will take over the abandoned nest of larger birds like hawks, eagles, herons, etc., usually 20-60 foot from the ground surface.
Hunting mostly at night they can sometimes be found perched high in a tree in the falling light of dusk waiting patiently to swoop down on spotted prey. These birds have good hearing and exception vision in low light.
During mating season, the male will feed the female in the nest. Once eggs have hatched both parents take part in rearing. Young tend to fly at 9-10 weeks but parents feed them sometimes for several months.
The Great Horned Owl reaches approximately 18- 25 inches in height with a wingspan of 39-57 inches and weighs between 32 and 88 ounces.