Great Horned Owl

Welcome to this week’s Wildlife of the Week!

This week’s Wildlife of the Week is the Great Horned Owl. With the exception of the snowy owl, it is the heaviest owl in North America, generally weighing from 2.5 to 3.5 pounds. Adult great horned owls range in length from 17 to 25 inches with an average wingspan of 3 to 5 feet. Females are somewhat larger than males. Its primary diet consists of rabbits, rats, mice and voles although it is an opportunistic hunter and will take other small mammals like squirrels, as well as birds, reptiles and amphibians. Their low-pitched hoo-hoo-hoo-hoo-hoo song lends itself to their colloquial name “hoot owl”.

Bubo virginianus Great Horned Owlet

They are well camouflaged, with mottled brown back and wings and a light brown breast with brown horizontal barring. Their feathers extend down to their feet. The bill is dark gunmetal-gray, as are the talons. All great horned owls have a facial disc that is lighter brown or gray with small tufts of feathers crowning their head (the “horns” that give the bird its name).

Like other owls species the great horned owl is capable of silent flight, making almost no discernible sound due to the structure and arrangement of their feathers. This capability allows for secretive hunting and stealthy attacks on their prey.

They are nocturnal and hunt almost exclusively at night. They have very large eyes that are highly adapted for nocturnal hunting. Hunting tends to peak between 8 PM and midnight and then resumes from 4 AM to sunrise.

Great horned owls are some of the earliest-breeding birds in North America, in part because of the lengthy winter nights that allow more hours of darkness for hunting. Courtship is from October to December and mates are chosen by December to January. In Alabama egg laying begins from December to early February. They often take over a nest used by some other large bird, sometimes adding feathers to line the nest but usually not much more. There are usually 2 eggs per clutch, but clutches range in size from 1 to 6 eggs (over 3 is uncommon, over 4 is very rare), with 10-12 weeks for fledging.

The best times of year to spot great horned owls on the refuge are winter when they are establishing nests and feeding young and summer after the young fledge.

The owlet in the video was spotted behind the Headquarters Building. (Video by Tom Ress)