Great horned owls are one of the most widespread owl species in North America. They are large, powerful owls that can be identified by their prominent ear tufts, or “horns”, that give them their name. Great horned owls use vocalizations as one of their main forms of communication. They have a wide repertoire of different calls that they use for different purposes throughout the year. Understanding the different vocalizations of great horned owls can give insight into their behavior and habits.
Common great horned owl calls
Some of the most common vocalizations of great horned owls include:
Territorial calls
The classic “hoot” of the great horned owl is one of its most distinguishable calls. This low, deep hoot is used by males to establish territories and attract mates. It can carry for several miles and has a rhythm of roughly 3-4 hoots per minute. Females may also give the territorial hoot but at a higher pitch than the males.
Contact calls
Great horned owls use contact calls year-round to communicate with mates and offspring. These calls are used to keep track of one another, especially when owlets beg for food. The male’s contact call is a low-pitched hoot while the female makes a higher-pitched “kewick” call.
Alarm calls
When disturbed at the nest, great horned owls may emit a screaming hiss or bill-snapping sound to signal danger to their mate or offspring. The male’s alarm call is a low-pitched “chuck-chuck-chuck” while the female makes a shrill “kee-kee-kee”.
Begging calls
Owlets in the nest give loud, raspy begging calls when they are hungry and waiting for the parents to deliver food. The hunger calls begin as peeps when the owlets are very young and develop into louder hisses and screeches as they get older.
Do great horned owls make different sounds?
Yes, great horned owls have a diverse repertoire of vocalizations that they use to communicate different meanings. Some key differences:
- Males and females make distinct calls, with the male’s voice lower-pitched
- Territorial calls are deep hoots used to establish territories
- Contact calls are used year-round between mates and offspring
- Alarm calls signal danger with hisses, bill-snapping, and screeches
- Young owlets beg for food with loud screeches and hisses
The wide variety of sounds made by great horned owls reflects the complex ways they communicate. Calls between males and females help them maintain pair bonds while begging calls by owlets elicit a feeding response from the parents. Understanding why great horned owls make different sounds provides insight into their behavior and social structure.
When do great horned owls make different sounds?
Great horned owls use specific calls during different times of year for distinct purposes:
Breeding season (late fall & winter)
During the breeding season, male great horned owls are very vocal, hooting repeatedly to claim territories and attract mates. Females may also give territorial calls but are generally less vocal. Once a pair bond has formed, the male and female maintain contact with frequent calling back and forth using contact calls.
Nesting & rearing young (early spring & summer)
When nesting, male and female great horned owls become very defensive of their nest site and young. They will issue loud alarm calls if disturbed to ward off potential threats. Once the eggs hatch, the owlets beg loudly and incessantly for food, eliciting feeding calls from the parents.
Fall & early winter
In the months leading up to breeding season, juveniles begin dispersing from their parents’ territories and great horned owls are nomadic. Vocalizations are less frequent but some contact and feeding calls may still occur between mated pairs and dispersing young.
What influences the sounds great horned owls make?
Several factors account for the wide repertoire of sounds used by great horned owls:
Purpose of call
Different vocalizations are used for distinct reasons, whether claiming territory, bonding with a mate, or begging for food. The purpose of the call influences its sound.
Age & sex
Juveniles sound different from adults while males and females also make distinct calls, with the female’s voice higher-pitched.
Time of year
Great horned owls are more vocal during breeding season and quieter in the non-breeding months. The frequency of calls changes throughout the year.
Urgency
Sounds conveying alarm or food-begging are louder, harsher, and more repetitive than routine contact calls between mates. The urgency of the message changes the nature of the call.
Individual variability
While calls from the same owl are consistent, there is some natural variation in the exact sound between individuals. No two great horned owls sound exactly alike.
By understanding why and when great horned owls vocalize, their diverse repertoire of sounds becomes more meaningful as communication tools.
How do great horned owls produce different sounds?
Great horned owls have specialized physical adaptations that allow them to produce diverse vocalizations:
Syrinx
The syrinx is the sound-producing organ in birds, located at the branch point between the trachea and bronchi. The syrinx allows great horned owls to produce two different sounds at once, enabling their hoots, hisses, and screeches.
Vocal tract
The owl’s vocal tract, consisting of the trachea, larynx, and beak, acts as a resonance chamber. Its length and shape filter sound waves to amplify certain frequencies and create the unique pitch and tone quality of great horned owl calls.
Airflow
Great horned owls control rate and volume of airflow over the syrinx to vary loudness, tempo, and intensity among different vocalizations. More vigorous airflow creates their louder alarm calls.
Specialized feathers
The owl has feathers around the beak and neck that function like moveable baffles, redirecting sound waves emanating from the syrinx. This allows great horned owls to finely modulate sounds.
Facial muscle control
Underlying facial muscles enable great horned owls to open their beak wide or make subtle position changes that also influence the filtering of sound as it exits the vocal tract. This control allows more sound variation.
The great horned owl’s complex vocal anatomy enables subtle control over a multitude of sounds to support their wide repertoire of communication. From soft contact calls to intense alarm screams, their flexible vocal abilities allow expression of different meanings.
What do the different great horned owl calls mean?
Interpreting the meaning behind great horned owl vocalizations provides insight into their behavior:
Territorial calls – “This is my territory!”
The male’s deep resonant hoots during breeding season advertise ownership of a territory to competitors and attract potential mates.
Contact calls – “Where are you?”
Softer hoots and kewicks exchanged by mates and parents/offspring help maintain connections and signal locations.
Alarm calls – “Threat detected!”
Screeches, bill-snapping, and hisses given in response to intruders indicate a warning signal and readiness to defend.
Food-begging calls – “Feed me!”
Loud, raspy hunger screams by owlets serve to trigger a feeding response from parent owls. The sounds signify an urgent need.
Individual identity
The great horned owl’s distinct vocal anatomy gives each bird a unique voice that allows individual recognition within pairs or family units.
Understanding the context and meaning of the great horned owl’s diverse vocal repertoire provides insights into their behavior, communication, and social bonds. Their ability to produce and interpret different sounds is key to their interactions.
How are great horned owl sounds adapted for their lifestyle?
Several key adaptations make great horned owl vocalizations well-suited for their nocturnal, predatory lifestyle:
Low frequencies
Great horned owl territorial and contact calls are generally of lower frequency. This allows their calls to travel farther through the forest at night. The hoots are impossible to locate and pinpoint.
Binaural hearing
Owls have asymmetric ear placement on their head. This allows superb directional hearing to detect and locate sounds in low light conditions. They can hunt by sound and avoid threats.
Stealth sounds
Soft contact calls between mates are designed not to attract attention and reveal owl locations to potential prey. But loud alarm calls quickly signal threats.
Asynchronous hatching
Age differences between offspring ensures that some owlets will always be begging for food, eliciting continual feeding responses from parents. Begging calls are adaptation to facilitate raising offspring.
Syrinx muscles
A muscular syrinx allows great horned owls to make soft-to-loud sound modulations for subtle or more urgent signaling. This supports effective communication under varying conditions.
The great horned owl’s impressive vocal abilities reflect key adaptations for thriving under the selective pressures of its predatory niche over millions of years. Communication via sound is a key evolutionary advantage.
How do great horned owl sounds compare with other owl species?
While great horned owls have a wide repertoire, other owl species also make specialized sounds suited to their needs:
Barred owls
Make “who-cooks-for-you” calls and have a more limited vocal range than great horned owls. Barred owl calls sound higher and more nasal.
Eastern screech owls
Make a haunting, descending whinny. Their calls are used in claiming territories and can convey threat displays.
Barn owls
Make harsh, raspy shrieks year-round. They have limited vocal repertoire compared to great horned owls.
Northern saw-whet owls
Make a short, repetitive tooting sound. They have a smaller sound repertoire than larger owl species.
Snowy owls
Usually silent but make loud barking sounds when threatened. They do not need varied calls like more social owl species.
Burrowing owls
Use nasal yips, chirps, and warning rattles. Have smaller vocal range than great horned owls but communicate year-round.
Comparisons illustrate how different owl species’ calls are adapted for their particular habitats, prey, and behavior patterns. The great horned owl relies more on varied vocalizations to facilitate their lifestyle than certain other owl species.
Conclusion
Great horned owls have a diverse repertoire of vocalizations that serve different communication functions. Their calls vary based on age, sex, season, intent, and urgency. The owls rely heavily on sound to interact and their adaptations allow effective signaling for territoriality, bonding, feeding, and warning threats. Understanding the meaning and context of the great horned owl’s sounds provides insight into their behavior and ecology. With a range of hoots, shrieks, hisses, and other vocalizations, the great horned is one of North America’s most vocal owl species.