The great horned owl, with its piercing yellow eyes and majestic plumage, has captured the imagination of humans for centuries. These nocturnal creatures possess an aura of mystery as they silently glide through the night skies. In this article, we delve into the captivating world of the great horned owl, unraveling its interesting facts and shedding light on its remarkable adaptations and behaviors.
1. They don’t have horns
The great horned owl is the largest of the “tufted” owls in North America. Despite its name, this species doesn’t actually possess horns. The name is derived from the prominent tufts on either side of their head, resembling horns. The function of these tufts remains a mystery, but some speculate that they could act as visual signals to other owls since they have the ability to be raised or flattened.
They are one of 17 owl species with the tuft feature on the head. The other species include the long-eared owl, the lesser horned owl, the spotted horned owl, etc.
Besides the “horns,” the owls are known for other distinctive characteristics, such as yellow eyes, and a white throat patch. These remarkable creatures display a diverse palette of colors, ranging from reddish-brown to black and white, as well as grey.
These colors vary across different geographical areas, depending on the average humidity levels in the owls’ habitats. In areas with lower humidity such as subarctic prairies or the southwestern deserts, the owls have paler coloring. On the other hand, in regions along the Atlantic side of Canada and the Pacific Northwest, where humidity is higher, the species tend to have darker plumage. The subarctic regions of Canada are particularly known for housing the palest-colored great horned owls, to the point where they may appear almost white (leucistic morph).
Great horned owls have a length between 17 and 25 inches and weigh about 3 pounds. However, the largest individual is in Alaska while the smallest is found in the Yucatan Peninsula and Baja California. Their wingspan can vary from 3 to 5 feet.
In terms of size, there is a notable distinction between females and males. Females tend to be larger, which may be attributed to their specific roles. Their larger size enables them to effectively incubate and care for the eggs. Conversely, the males with smaller sizes can hunt effectively in narrow forest openings.
2. They have great abilities
One of the most special features of these owls is their large bright yellow eyes, which are among the biggest eyes found in terrestrial vertebrates. This remarkable characteristic significantly enhances their vision and prowess in hunting.
Their cylindrical-shaped eyes function as zoom lenses, endowing them with exceptional long-range vision, surpassing that of birds with round-shaped eyes. With this expansive binocular field of view, owls gain a comprehensive perspective of their surroundings.
Although great horned owls can only see things in black and white, they still possess remarkable night vision. Their huge eyes are 35 times more light-sensitive than our eyes.
What sets them apart is the presence of three eyelids. Each eyelid has a unique function: the outer eyelid aids in blinking, the middle one shields the eye during sleep, and the third one protects the eye from airborne particles while in flight.
Having all kinds of great features, these eyes cannot be moved up and down or from side to side. To make it up for this, the owls rotate their entire head to observe their surroundings. But, unlike what you often think, they cannot perform a complete 360-degree rotation. They can only achieve a 270-degree range of motion, which is still impressive, thanks to their 14 neck vertebrae—twice the number found in humans.
Great horned owls exhibit an extraordinary sense of hearing, allowing them to detect sounds from distances as great as ten miles. Their acute hearing is enhanced by specialized facial disks that can adapt to channel sound directly into their ears. This grants them a hearing capacity that is ten times more potent than that of humans. For example, they can detect a mouse’s careful footsteps on a twig, even from a remarkable distance of 75 feet (23 meters).
Their ears are holes located beneath their tufts, with the left ear lower than the right one. This unique positioning provides them with a form of sound “depth perception.”
Although having excellent vision and a sense of hearing, these owls have a poor sense of smell.
However, this brings them new opportunities, instead of disadvantages. Thanks to this, they can hunt and eat skunks without being affected by their stink smell.
The great horned owls possess the remarkable ability to camouflage themselves within their environment as they search for prey, thanks to the intricate patterns adorning their feathers. These feathers are amazing. They keep the owls warm on the coldest winter nights so that the owls don’t need to hibernate or migrate.
The distinctive comb-like feathers also grant them the ability to fly silently. The fringed leading edge of their feathers eliminates any frictional noises, letting these owls stealthily approach their prey without being detected.
3. They are formidable hunters
The great horned owl is renowned for its insatiable hunger and displays a wide-ranging prey species, with at least 253 identified so far. These carnivores are nocturnal, primarily hunting at night, with a preference for targeting both mammals and birds. Their diet typically consists of 90% mammals and 10% birds.
Their mammal prey encompasses a wide array of creatures, including skunks, porcupines, rabbits, armadillos, squirrels, hares, gophers, moles, mink, raccoons, rats, muskrats, voles, bats, mice, shrews, and intriguingly, even domestic cats and dogs. Among these options, hares and rabbits are their favorite food. About bird food, the owls often eat other owls (except snowy owls), pigeons, ducks, red-tailed hawks, crows, woodpeckers, gulls, bitterns, chickens, turkeys, and swans. Coots and ducks are their preferred choices.
Additionally, these great horned owls occasionally consume insects, reptiles (including turtles, lizards, young alligators, and snakes), and amphibians (such as toads, frogs, and salamanders). They also feed on fish, crayfish, centipedes, spiders, scorpions, and animals that have been killed by vehicles on the road.
The species acquire all the necessary hydration for their bodies from the water content present in the food they consume.
With their remarkable adaptions, as discussed in part 2, these birds possess the qualities of fearsome hunters. They usually choose lofty tree branches as their vantage points, carefully surveying open spaces such as wetlands, meadows, and forest boundaries in search of potential prey. Then, they swoop down from elevated vantage points, descending swiftly towards the earth, attacking and seizing their unsuspecting prey.
Once grabbed by the large talons of great horned owls, the unfortunate prey is killed in an instant. With a gripping force of 28 pounds, the talons of these owls can prevent any chance of escape from the prey and crush their spine easily.
The great horned owls also hunt by gliding gracefully above the ground, wading into the water to catch fish and frogs, or traversing on land to capture smaller prey, such as infiltrating chicken coops to target domestic fowl.
After getting prey, the owls will eat them whole if the prey is small, such as rabbits or rodents. With bigger prey, they will bring them to feeding perches or the nest where they tear them apart with their beak. These owls do not possess the capability to store food for future digestion. In times of plenty, they might accumulate several rabbits or gophers within their nests.
Without teeth, the birds swallow the prey. Their gizzard is in charge of breaking down proteins, fats, and liquids while eliminating indigestible components. The residual matter, such as fur, feathers, and bones undergoes compression within the owl’s digestive system, resulting in the formation of dry pellets. The owls will expel those pellets by regurgitating them.
As apex predators, great horned owls typically encounter few threats from enemies. However, their eggs and offspring are susceptible to many species, such as bobcats, large hawks, foxes, crows, eagles, raccoons, ravens, and coyotes.
4. Great horned owl Habitat
The great horned owl comes from North America. These species can be spotted throughout the US, encompassing Alaska, and expanding further south into Central America and South America.
They live in a wide range of habitat preferences, from canyons and forests to clearings and open fields within agricultural areas. Nevertheless, they are also found in urban settings, including residential areas, parks, and industrial developments.
The owls establish and defend territories, typically occupying an average home range of about 1.5 square miles. These territory sizes can differ significantly depending on the location. For instance, populations in Ontario and Alaska tend to have larger home ranges, while those in California and Texas have relatively smaller ones.
Great horned owls are renowned for their distinct traits and behaviors. Like other owls, these species are most active at night, tirelessly hunting for food. During the daytime, they roost in tranquil, dimly lit locations such as hollow tree trunks. However, you may occasionally see them engage in daytime activities.
Contrary to numerous bird species, these owls exhibit a sedentary lifestyle. They do not migrate but opt to stay in their selected habitats year-round. Nevertheless, there have been some cases where they, great horned owls from Alberta and Saskatchewan in Canada, move southward. This phenomenon is referred to as an “irruption.”
This occurrence takes place when the population of their prey which is snowshoe hares decreases. This makes the owls have to move to other regions with more plentiful food, such as Nebraska, Minnesota, Iowa, the Dakotas, and Kansas.
These creatures are territorial birds, maintaining their territories for long periods of time, even beyond a single nesting season. To establish their authority and mark their territory, they produce powerful hoots, effectively conveying a message to others to keep their distance. You may hear their unique hoots because their hoots are often used in nighttime scenes depicted in movies and television.
Compared to females, males may exhibit a smaller size, but they boast a larger voice box, enabling their hoots to resonate in a deeper pitch. This distinct vocalization leads to occasional duets between male and female owls, as their calls harmonize with one another. Apart from hoots, great horned owls also emit a diverse range of sounds, from screeches to barks. These owls are nocturnal, you cannot hear them hooting during the day.
Great horned owls are aggressive birds. They will attack predators, even humans to protect their territories, their partners, and their offspring. However, they are not so dangerous that can cause you hurt or injury.
The breeding season of the great horned owl typically takes place during winter. To attract their mates, they create mating calls and employ a captivating display consisting of bobbing up and down and puffing up their feathers. These remarkable birds are monogamous, known to form long-term partnerships, potentially even for life. However, they can also mate with multiple females.
These owls primarily choose to build their nests in trees, nest boxes, or cliff ledges. They display opportunistic behavior by frequently taking over nests that originally belonged to squirrels or other birds of medium to large size, such as eagles, hawks, crows, and herons. In desert areas, they might also make use of abandoned woodpecker holes discovered in big cacti.
The owls engage in their mating season before other birds, enabling them to secure a nest before those birds begin their reproduction activities. One more benefit of breeding during this time is the extended duration of nighttime hours, which allows the birds to have more time to hunt and fewer daylight hours to face potential threats to their nest from enemies.
Each year, the female owl lays a batch of 1 – 3 white eggs adorned with small bluish-tinted spots. She will incubate these eggs for approximately 30 to 45 days. After that, the eggs hatch with either gray or yellowish hazel eyes. The eye colors of these newborns will change to vivid bright yellow shades within their first month of existence.
The chicks are fed and protected by both parents. If there is an intruder, the mother will aggressively pose an imposing stance, extending her wings and fluffing her feathers. This display serves as a deterrent, cautioning potential intruders against engaging in any conflicts.
Around the age of five weeks, the young owls are ready to fledge and explore the branches near their nest. When they are 9 to 10 weeks old, these juveniles have developed the ability to fly. The parents keep taking care of their offspring for several months.
The average lifespan of great horned owls is around 13 years with the oldest wild great horned owl living up to 28 years old. But in captivity, these birds can live up to 50 years.
7. Threats and Conservation status
Currently, the great horned owl thrives abundantly throughout its entire habitat. There are about 6 million individuals of this owl all over the world. Nevertheless, it continues to encounter various challenges, one of them being habitat loss.
The profound consequences of wildfires are a matter of great concern, as they destroy habitats and impede their natural recovery, especially when they happen frequently. Furthermore, spring heatwaves present a danger to immature birds in their nests.
Human activities are significant contributors as well. In spite of the presence of federal regulations, these birds continue to endure persecution from certain individuals due to their predation on game birds and poultry.
Great horned owls are also susceptible to a range of detrimental substances, such as pesticides and anticoagulant rodenticides. These substances are the main killers of many birds, including these owls. Vehicle collisions contribute to the challenges faced by this species.