by Bee Harris, PWL Member
Imagine sending out a scout team to gather information on the enemy. Their senses are on high alert and yet, the enemy can stealthily pick your scouts off one by one. Who has such silent predatory skills?
In Texas, when night falls, one of the most powerful and captivating predators of the night emerges – the Great Horned Owl – a truly remarkable creature that inhabits forests and semi-forested land. It is one of largest owls found not just in Texas, but in the Americas with its wide range resulting in diverse prey from over 250 species.
These owls don’t migrate unless the environment becomes less friendly to their species survival. If there are no old nesting sites from large birds available, they will look elsewhere. They hoot to protect their territory with the female pitch being higher than that of the male’s. (You are more likely to hear and identify them in fall and winter when they are most vocal.)
They are nocturnal and most active at dawn and dusk. They can be heard at night during the breeding season and during the day in winter, when food is scarcer. They hoot, but will also clack their bills – like the sound of an old typewriter – when disturbed or under stress.
Winter is best for owl observations because this is when they are most vocal as they search for a mate. They are the enemy, often mobbed and divebombed by flying raptors and other birds – if you were prey, having this owl in your vicinity would be just plain scary. Hearing multiple birds cawing in warning can be an opportunity to catch a glimpse of a Great Horned Owl.
Great Horned Owls eat mostly birds and mammals. When small prey (insects, reptiles, fish, and carrion) is scarce, they will hunt larger prey, such as osprey. They either swallow their food whole or tear it to pieces. They will also store food and if frozen they will sit on it to incubate it. These owls keep other animals in check. They are one of the only known predators of the skunk – because of a limited sense of smell –helping to keep the skunk population in control. Great Horned Owls eat and digest animals whole. Around 10 hours later, they cough up a pellet about 2 inches in length containing bones, feathers and beaks (which are indigestible).
A 4-pound owl can kill an animal that is 10 pounds or so. However, it can’t carry it off if it’s half their weight or more. When an animal is too big, they will tear it into pieces with their hooked bill and massive sharp talons.
Their talons can rotate/swivel around. The middle claw has a sharp edge for ripping and tearing. The pressure of their talons is 2-500 pounds, making them the strongest – with the exception of the Golden Eagle.
The horned owl has the highest wing loading (ability to carry their own weight in food) of any raptor. Their wingspan ranges from 40-60 inches and their height from 18-25 inches, the female being the largest by about 2 more pounds.
Breeding is typically January-February and mating is for life. They nest in old, abandoned nests. The female sits on eggs (1 to 4 eggs) with an incubation of 30-40 days. Both parents provide food for their young. They defend their nest well. Eggs hatch after about 6 weeks. The young birds begin to fly 9-10 weeks after birth. Then, they span out to find territories.
They are incredibly adapted to night hunting. These owls don’t have eyeballs, but eye tubes. This is why they must be able to turn their heads – astonishingly, 270 degrees due to extra vertebrae in their neck. Their eyes – wider inside the head – are made for optimal night vision, but it’s their ears that are most important.
The owl’s facial discs are formed by feathers whose specific job is to create a path to its ears, which are located under its head feathers. The right ear is higher than the left enabling the owl to listen to sounds asynchronously. This helps it have great accuracy in pinpointing sound origin. It is the ears that tell the eyes where to focus.
Their coloration and “horned” tufts of feathers on top of the head are for camouflage, but their incredible stealth lies in having fringed (comb) wing feathers which muffle the flapping of their wings as they approach prey. The stealthy Great Horned Owl has garnered the reputation of being the “sit and wait predator.”
Further reading:
The Texas Breeding Bird Atlas, Great Horned Owl
https://txtbba.tamu.edu/species-accounts/great-horned-owl/
Great Horned Owl. Blackland Prairie Raptor Center
https://bpraptorcenter.org/great-horned-owl/
Cornell Lab, All About Birds. Great Horned Owl
https://www.allaboutbirds.org/guide/Great_Horned_Owl/id
Houston Arboretum & Nature Center. The Great Owl Rescue
https://houstonarboretum.org/the-great-owl-rescue/
Animalia.bio. Great Horned Owl
https://animalia.bio/great-horned-owl