Hummingbirds are known for their ability to hover in midair and for the humming noise produced by their rapidly beating wings. However, not all hummingbird species vocalize. Some species are quite quiet, while others make chirping, twittering, or even singing sounds.
Reasons Why Some Hummingbirds Vocalize
There are several reasons why certain hummingbird species use vocalizations:
- Attracting mates – Male hummingbirds often sing complex songs to court females. The songs showcase the male’s health and fitness.
- Communicating with mates – Mated pairs may use contact calls to communicate with each other, especially during the breeding season.
- Defending territories – Many hummingbirds are territorial, especially when feeding. They use aggressive vocalizations to chase intruders away.
- Begging calls – Baby hummingbirds (nestlings) make loud, repetitive noises when begging for food from their mothers.
- Distress calls – Hummingbirds may make alarm or distress calls when threatened by predators.
So vocalizations play an important role in mating, communication, territoriality, parenting, and warning of danger. The noisier species often live in dense habitats like rainforests where visibility is limited. Vocalizations help maintain contact.
Reasons Why Some Hummingbirds Are Quiet
On the other hand, some hummingbird species are surprisingly quiet and non-vocal, including:
- Ruby-throated Hummingbird
- Anna’s Hummingbird
- Costa’s Hummingbird
- Calliope Hummingbird
There are a few reasons why these hummingbirds do not vocalize much:
- Solitary lifestyle – Many non-vocal species are less social and do not form breeding pairs. They have little need for vocal communication.
- Open habitats – Species in open meadows or deserts have better visibility. Less need for contact calls.
- Predation risk – Songs and calls may attract predators. Quiet species try to avoid detection.
- Energy conservation – Vocalizing takes energy, so birds in challenging environments may refrain from calling.
- Alternate communication – Some hummingbirds rely more on visual displays, reducing need for vocalizations.
So a solitary lifestyle in an open environment seems to favor quieter communication in some hummingbird species. Vocalization takes energy and risks attracting predators, so refraining from calling has its advantages.
Characteristics of Noisy vs. Quiet Species
We can summarize the typical characteristics of vocal and non-vocal hummingbird species:
Noisy Species | Quiet Species |
---|---|
Live in forests and dense habitats | Live in open meadows, deserts, suburbs |
Social, form breeding pairs | Solitary, less social breeding |
Use vocalizations for courtship, communication | Rely more on visual displays |
Very territorial, defend feeding areas | Less territorial |
Limited visibility in habitat | Good visibility in habitat |
Of course, there are exceptions to these patterns. But in general, dense forest species like the Blue-throated Hummingbird tend to be more vocal, while solitary species like the Ruby-throated Hummingbird are quieter.
Courtship Displays and Sounds
When trying to attract a mate, male hummingbirds engage in elaborate courtship displays. These can involve a mix of visual displays and vocalizations.
Visual Displays
Visual courtship displays by male hummingbirds include:
- Aerial flights and dives – Males fly in loops, arcs, or circles high in the air, then dive suddenly and rapidly pull up at the bottom.
- Tail feathers – Special tail feather structures (streamers, flags, spikes) may be shown off.
- Throat feathers – Males puff out their colorful throat feathers.
- Reflected light – Males orient to show off iridescent crown or gorget feathers.
These visual displays demonstrate the male’s aerobatic skill and the health of his flight feathers and elaborate plumage features. Females pay attention to these characteristics when selecting a mate.
Vocalizations
The vocalizations that accompany courtship in noisy hummingbird species include:
- Loud song – Primary advertising song to attract females.
- Buzzing – Made by tail feathers during dives.
- Chattering – Aggressive call made when chasing another male intruder away.
- Whistling – Short contact call made near the nest.
- Shrill chips – Begging call of females seeking courtship feeding.
The species-specific songs of male hummingbirds are usually quite complex. For example, the Blue-throated Hummingbird has a buzzy, trilled song, while the Magnificent Hummingbird’s song is a series of sharp, whistling notes.
Vocal Learning
Researchers have discovered that some hummingbird species have the rare ability to learn their vocalizations. Most birds have innate, genetically programmed songs. But certain hummingbirds mimic the sounds around them and may invent new songs.
So far, vocal learning has been demonstrated in these hummingbird species:
- Green Violet-ear
- Green Hermit
- Wedge-tailed Sabrewing
- White-necked Jacobin
- Crimson Topaz
This ability suggests greater vocal plasticity and flexibility in brain structure compared to most birds. It may help hummingbirds adapt their vocal communication to different environments.
Functions of Hummingbird Songs and Calls
To summarize the main functions of hummingbird vocalizations:
Vocalization Type | Function |
---|---|
Courtship songs | Attract mates |
Chase calls | Defend territories |
Begging calls | Request food from parents |
Contact calls | Communicate with mate or offspring |
Alarm calls | Warn of predators |
Understanding these different hummingbird vocalizations provides insight into their social interactions and behaviors.
Impact of Habitat on Vocalizations
Hummingbird species living in different habitats show adaptations for optimal communication in those environments:
- Rainforests – Dense vegetation and low visibility selects for species with loud, high-pitched songs that carry over distance. Examples are the Rufous-crested Coquette and Gould’s Jewelfront.
- Mountain forests – Lower oxygen at high elevations favors efficient, rapid trills in songs. Examples are the Giant Hummingbird and Amethyst-throated Hummingbird.
- Deserts and scrub – Open areas with good visibility select for less vocalization and more visual displays. Examples are Costa’s Hummingbird and Broad-billed Hummingbird.
- Suburbs/parks – Moderate vegetation allows both visual and vocal communication. Examples are the Ruby-throated Hummingbird and Allen’s Hummingbird.
So habitat plays a key role in shaping hummingbird vocal behavior and communication strategies.
Unusual Sounds
While most hummingbird species vocalize with songs, calls and trills, a few have developed very unusual sounds:
- The Streamertail makes a loud cracking sound with its tail feathers during courtship dives.
- The endangered Palila species produces a strangled-sounding alarm call that led to its Hawaiian name meaning “noisy one.”
- The Plovercrest makes a low u-wa cow-like sound, reminiscent of a dove.
- The Cuban Emerald and Bee Hummingbird create a distinctive insect-like buzzing with their wings.
These unique sounds likely serve special communication functions for each species in their particular habitat.
Mimicry
A few clever hummingbird species have even managed to mimic the vocalizations of other birds:
- The Green Hermit can perfectly mimic the songs of flycatchers, tanagers, and other species it associates with.
- The Black Jacobin mimics the contact calls of the Blue Dacnis.
- The Rufous-tailed Hummingbird incorporates sounds from finches and woodpeckers into its repertoire.
Mimicry may help expand the vocabulary of hummingbirds. But in some cases, it may also function to deceive other species when competing for food or territories.
Current Threats to Hummingbird Vocalizations
Unfortunately, some current trends may threaten the vocal behavior of hummingbirds:
- Habitat loss – Deforestation is altering the habitat types that shape hummingbird vocal adaptations.
- Climate change – Changing temperatures and precipitation may affect timing of hummingbird migrations and breeding.
- Noise pollution – Noisy urban environments may mask hummingbird songs and calls.
- Pesticides – Chemicals may disrupt hormones involved in vocal learning and production.
More research is needed on how these issues impact hummingbird vocal behavior over the long term. Efforts to conserve their habitat and reduce pollution will help maintain healthy communication.
Conclusions
In conclusion, hummingbird vocalizations play an important role in courtship, defending territories, parent-offspring communication, and warning against predators. Habitat shapes the selective pressures acting on vocalizations. Hummingbirds in forests tend to be more vocal due to limited visibility, while open habitat species rely more on visual displays.
A small number of hummingbird species have even developed vocal learning skills similar to songbirds. Their ability to invent new sounds and mimic other species hints at greater intellectual capacity. Understanding the diversity and functions of hummingbird vocalizations provides insight into their social behavior, habitat adaptations, and evolutionary history.