The night heron is a medium-sized heron that is most active at night or during dusk and dawn. There are two main species of night heron: the black-crowned night heron (Nycticorax nycticorax) and the yellow-crowned night heron (Nyctanassa violacea). These birds make a variety of noises and calls, which can help birders identify them even when they are hidden in vegetation or darkness. In this article, we will explore the different sounds that night herons make and what they signify.
Croaking Call
The most common vocalization of the night heron is a deep, guttural croaking sound. This croak is often represented as a “wraark” or “waak” noise. It is used year-round by night herons of all ages and both sexes. The croaking serves several purposes:
- Territory Defense – Male night herons stake out nesting territories and use croaking calls to warn off intruders.
- Courtship – Croaking plays a role in attracting mates and strengthening the pair bond.
- Alarm/Anxiety – Night herons give croaking calls when startled or distressed.
- Staying in Contact – Family groups keep in touch with croaking calls.
The croaking of night herons carries well over distance. During the breeding season, which varies by latitude, the croaking chorus of a heronry can be heard from quite far away. Neighboring males may engage in “croak-offs” to assert their dominance. The croak call is often the first clue that night herons are nesting in an area.
Squawking Call
In addition to croaking, night herons have a louder, more abrasive call that is best described as squawking or screaming. These calls tend to be more variable in pitch and texture than the croaking sound. Reasons night herons may squawk include:
- Alarm – Used when the bird is surprised, agitated, or feels threatened.
- Fighting – Given when disputing over food, nest sites, or mates.
- Fledgling Calls – Hungry or distressed chicks will squawk loudly to get their parents’ attention.
The squawking call is harsher and more sudden than the croaking sound. It can help observers pinpoint where a night heron is hiding or what is causing it distress. During battles at the heronry, the squawking and croaking of agitated birds combines into a cacophony of noise.
Begging Calls of Young
From the time they hatch until they fledge several weeks later, juvenile night herons begging call almost constantly at their parents for food. The young birds give high-pitched, whistling peeps and cheeps. As the chicks get older, these calls become louder and more assertive, transitioning into the squawking sound of fledglings.
The begging cheeps and peeps are often the first sign that night heron eggs have hatched. Since night herons nest in concealed locations, the sound helps birders know there are chicks in a nest they cannot see directly. The constant chorus of begging calls creates a lively din in nesting colonies.
Courtship Calls
During courtship, night herons have specialized vocalizations and displays to attract mates and cement pair bonds. These include:
- Bill-snapping – Males snap their bills as a visual and auditory display.
- Neck-stretching – Birds elongate their necks and give low, gutteral calls.
- Whisper song – Male approaches female while whistling softly.
- Courtship feeding – Male brings food to female accompanied by grunt-like calls.
The combination of physical displays and soft vocalizations helps pairs reaffirm their bonds. Calls get louder and more frequent as pairs make final preparations for nesting season.
Difference Between Species
The calls of black-crowned and yellow-crowned night herons are nearly identical. However, there are subtle differences:
- Black-crowned croaks are lower pitched on average.
- Yellow-crowned are more nasal and high pitched.
- Black-crowned have a gravelly, two-note croak while yellow-crowned make a single note call.
- Yellow-crowned juveniles make louder, more insistent begging calls.
The calls are similar enough that they can be difficult to distinguish in mixed heronries. But familiarity with both species helps discern the unique qualities of each.
Other Noises
Beyond vocalizations, night herons make other sounds:
- billing clicking or clattering during agitation or courtship.
- splashing noises when capturing prey in the water.
- rustling of wings and foliage when departing the roost.
Attentive observers can use these auditory clues to help locate night herons and interpret their behavior. With practice, even hard-to-see night herons give away their location and actions to diligent birders.
Conclusion
The night heron has a wide repertoire of croaks, squawks, begging calls, courtship vocalizations, and other noises. Each sound has a distinct purpose, from defending territory and attracting mates to bonding with family groups. The most frequent call is the low, croaking “wraark” but loud alarm squawks quickly help pinpoint agitated birds. Juvenile begging peeps reveal the location of hidden nests. And courtship calls like bill-snapping help strengthen pair bonds. An observer knowledgeable in the noises of the night heron can detect and learn about the birds, even under cover of darkness. So next time you are out at dawn or dusk, listen closely for the tell-tale sounds of these fascinating nocturnal herons.
Call Type | Description | Purpose |
---|---|---|
Croaking | Low guttural “wraark” or “waak” sound | Territory defense, courtship, alarm, staying in contact |
Squawking | Loud, abrasive, variable screams | Alarm, agitation, fighting, fledgling begging calls |
Begging Calls | High-pitched cheeps and peeps | Juveniles begging for food |
Courtship Calls | Bill-snapping, neck-stretching, whisper song, grunts | Attracting mates and strengthening pair bond |
Species | Call Qualities |
---|---|
Black-crowned Night Heron | Lower pitched, gravelly croak |
Yellow-crowned Night Heron | Nasal, high pitched, single note |
Common Night Heron Noises
- Croaking – guttural, territorial call
- Squawking – loud alarm call
- Begging calls – cheeps of chicks
- Courtship calls – bill snapping, whisper song
- Startled bill clattering
- Splashing sounds when hunting
- Wing rustling when fleeing
Purpose of Sounds
- Defend nesting territory
- Strengthen pair bonds
- Communicate alarm
- Keep family groups together
- Attract mates
- Guide parents to feed chicks
Differences by Species and Age
- Black-crowned lower pitched than yellow-crowned
- Yellow-crowned more nasal and high pitched
- Juvenile begging louder and more insistent
- Adults make courtship sounds
How to Identify Night Herons by Sound
- Listen for deep croaking or loud squawking
- Note begging calls to find hidden nests
- Distinguish subtle differences between species
- Learn meaning of sounds in context
- Use calls to locate hard-to-see birds
Conclusion
In summary, the night heron is a vocal species that uses a variety of croaks, squawks, and other sounds to communicate and interact. Each noise has a specific purpose, whether defending a nest site, strengthening bonds, or begging for food. An observer knowledgeable in night heron vocalizations can gain valuable insights into the birds’ behavior and ecology, even when they are out of sight. So next time you are outdoors at night or dawn, open your ears to the unique sounds of the night heron!