Hummingbirds are known for their small size, beautiful iridescent feathers, and of course their loud, buzzing hum. But why exactly are hummingbirds so noisy? There are a few key reasons these tiny birds make so much sound relative to their size.
Anatomy of Hummingbird Sounds
The primary source of hummingbird vocalizations is their wings. As they flap their wings up to 80 times per second to hover and fly, the rapid motion causes air to move over their wing feathers creating a hum or buzz. The sound is amplified by the stiff rim of their outer primary feathers vibrating as air rushes over them.
Additionally, a hummingbird’s tail feathers and vocal chords can contribute to noise production. Tail feathers may flutter or spread creating a whirring sound. And while hummingbird calls and chirps are much quieter than wing buzzing, their vocalizations from the syrinx organ in their throats add to the variety of noises.
Reasons for Loud Humming
There are several theories as to why hummingbird wings and bodies evolved to be so noisy for their size:
- Territorial defense – Loud buzzing hums are thought to help hummingbirds defend feeding territories and signal boundaries to other individuals. The sounds let competitors know the territory is occupied.
- Courtship – Male hummingbirds often produce dive displays with loud buzzing sounds near female hummingbirds as part of mating rituals. The wing noise likely helps attract females.
- Predator deterrence – Some experts think the loud, fast wing beats could mimic the sound of bees or other stinging insects as a form of mimicry to deter potential predators. The humming may warn predators away.
- Flower location – The wing hums generate sound waves that reflect off nearby objects, which may help hummingbirds locate flowers and food sources efficiently, especially in dense vegetation. The echoes guide them.
- Displays of fitness – During courtship, the male with the loudest, highest pitched hum likely signifies the fittest mate with the strongest wing muscles and aerodynamics. Females likely evolved to prefer louder wing hums.
Unique Adaptations for Volume
Hummingbirds have several unique anatomical adaptations that allow them to produce relatively loud sounds compared to other similarly sized birds:
- Their wings beat incredibly fast, up to 80 times per second, creating more sound with each flap.
- They can rotate their wings at the shoulder socket to produce aerodynamic hums during specialized display dives and turns.
- The rigid outer primary wing feathers vibrate and cause resonance or amplification of the base hum.
- The streamlined shape of feathers on a hummingbird’s wing make the wings stiff and well-suited for flapping at high frequencies.
- Large flight muscles make up 25-30% of their total body weight allowing sustained high speed flapping.
Differences Between Species
While all hummingbird species make a similar humming or buzzing sound with their wings, the loudness, pitch, and tone can vary based on specific adaptations of each species.
- The bee hummingbird is the smallest species at just 2 inches long, yet still produces a surprisingly loud hum.
- Larger hummingbird species tend to have lower-pitched, richer sounding hums than smaller varieties.
- Male Anna’s hummingbirds can produce loud, complex songs by vibrating their outer tail feathers during dives.
- Streamertail hummingbirds have exceptionally shaped outer wing feathers that produce a unique lower-pitched hum.
- The scissor-tailed hummingbird has distinctive outer wing feathers that generate a louder, higher pitched buzz.
Measuring Hummingbird Noise
Scientists use specialized audio recording equipment and controlled experiments to study the noise produced by hummingbirds. Key aspects researchers measure include:
- Frequency or pitch – Measured in Hertz (Hz), higher frequencies equate to higher pitched sounds.
- Sound pressure level – Measured in decibels (dB), indicates relative loudness. Hummingbirds register between 62 to 85 dB during courtship.
- Harmonics – Hummingbird wing hums contain multiple layers of sound frequencies at once, creating a harmonic, resonating effect.
- Tempo – The speed or beats per minute of hummingbird wing flaps, often measured with high speed cameras.
- Timbre – The unique quality or color of sound that distinguishes hummingbird species and behaviors.
Advanced sound spectrographic analysis allows fine details of hummingbird acoustics to be examined. This provides insights into how their wing anatomy, speed, and display behaviors influence noise production.
Impact on Hearing
The loud noises hummingbirds create with their energetic wing flapping and diving displays does come at a cost. Studies have shown that hummingbirds have reduced hearing sensitivity compared to other related bird species.
The constant exposure to self-generated buzzing and whining sounds is thought to cause hearing loss or degradation over time. However, the hummingbird’s vital ability to hear high frequencies needed to locate insects and flowers remains intact.
Table summarizing key details on hummingbird noise:
|Volume||62 – 85+ decibels|
|Pitch||High frequencies, 130 – 8,000 Hz|
|Source||Wings, tail feathers, syrinx|
|Purpose||Communication, territoriality, courtship|
|Velocity||Up to 80 wingbeats/second|
|Variability||Pitch and tone differs between species|
|Cost||Hearing loss induced over time|
Conclusion: A Delicate Balance of Speed and Sound
The mere 2-20 grams of a hummingbird’s body hides an incredible muscle engine capable of beating their wings faster than any other bird. The resultant loud buzzing hum sounds may be annoying to human ears, but they allow hummingbirds to communicate, display fitness, locate food, and deter predators.
The adaptations that produce loud hums come at a cost of some hearing loss. But ultimately the speed, agility, and noise enable these energetic birds to survive. The next time you hear the loud buzzing of a hovering hummingbird, listen more closely and appreciate the finely tuned balance of anatomy, behavior, and sound.
Frequently Asked Questions About Hummingbird Sounds
Why are male hummingbird sounds different than females?
Male hummingbirds have specialized wing and tail feather adaptations to produce dive displays with loud buzzing sounds and songs to attract mates. Females lack these display adaptations and vocalizations are limited to softer chips and chirps.
How do hummingbird wings make noise?
Air moving rapidly over a hummingbird’s small, stiff wing feathers causes them to vibrate. This vibration generates the base hum, which is amplified by the wingtips. Tail feathers can also flutter to add sound.
Do hummingbird sounds vary by species?
Yes, the pitch, tone, volume, and complexity of sounds differ between hummingbird species based on anatomical adaptations like wing shape, tail feathers, body size, and display behaviors.
How loud is a hummingbird?
Hummingbird hums and dive displays range from about 62 to 85+ decibels measured up close. By comparison, normal human conversation is about 60 dB.
Do hummingbirds get hearing loss from their own noise?
Research indicates hummingbirds do experience some hearing degradation over time from constant exposure to the high frequency sounds of their wings and calls. But they retain hearing sensitivity critical for finding food.
Why do hummingbirds make noise with their tails?
Specialized tail feathers allow male hummingbirds like Anna’s to produce chirps, whistles, and additional buzzing sounds during courtship dives. The tail noises make displays more complex and impressive.
Can you measure hummingbird sounds?
Yes, scientists use audio recording devices and sound spectrographic analysis to measure the frequency, pitch, tempo, volume, and timbre of hummingbird vocalizations in fine detail. This reveals insights into hummingbird acoustics.
How fast do hummingbird wings flap?
Hummingbird wing speed varies by species, but ranges from 12 beats per second up to an incredible 80 beats per second during hummingbird courtship dives. This rapid flapping causes the loud hum.
Do bigger hummingbirds make lower-pitched hums?
Generally, yes. Larger hummingbird species with bigger wings tend to produce lower frequency, richer toned hums compared to smaller hummingbird varieties.