Why do hummingbirds flare their tails?

Hummingbirds are known for their incredible flying abilities and their beautiful, iridescent plumage. One interesting behavior that hummingbirds exhibit is tail flaring – rapidly moving their tail feathers back and forth in a fan-like motion. This eye-catching display is used by hummingbirds for a variety of reasons. In this article, we’ll explore the major theories behind tail flaring in hummingbirds and why these tiny birds use tail motions to communicate.

Theories Behind Hummingbird Tail Flaring

There are a few main hypotheses as to why hummingbirds flare their tails:

Attracting Mates

One of the most common reasons male hummingbirds flare their tails is to attract females. The rapid fanning motion shows off the male’s colorful tail feathers and signals to watching females that he is strong, healthy, and ready to mate. Studies have shown that female hummingbirds do pay attention to tail flairing and are more likely to be attracted to vigorous displays.

During courtship, a male hummingbird will fan his tail feathers, spread his wings, and perform dramatic dives and climbs to impress the female. If she is interested, she will reciprocate by flaring her own tail. Once paired, the male and female may continue to flare tails at each other as a way to strengthen their bond. The degree of flairing indicates the level of courtship.

Communicating Aggression

Hummingbirds are very territorial creatures and they will defend their feeding areas fiercely against intruders. A rapid tail flaring is one way hummingbirds signal aggression towards another encroaching bird. The flashing tail warns the intruder to back off or prepare to fight. Even slight variations in fanning can indicate different levels of anger and how likely the hummingbird is to attack.

Research has shown that when defending territories, male hummingbirds flare their tails much more frequently than females. And hummingbird species that tend to be more aggressive overall, like Anna’s and Rufous hummingbirds, fan their tails at higher rates than more passive species. Tail flaring is an effective, non-contact way to convey a hummingbird’s combative nature from a distance.

Dispelling Heat

Due to their extremely fast metabolism and the huge amount of energy they expend flying, hummingbirds generate a lot of internal body heat. Some scientists believe that tail flaring helps hummingbirds release excess heat so they don’t overheat during flight or while feeding on nectar.

By fanning their tail feathers, hummingbirds expose more surface area to the surrounding air allowing more heat to quickly dissipate. Research has recorded hummingbirds tail flaring more often on hot, humid days which supports this thermoregulatory function. The caudal feathers are also highly vascularized with lots of blood flow making the tail an ideal place to release heat.

Stabilizing Flight

The rapid motion of hummingbird wings – up to 200 flaps per second – creates aerodynamic forces that must be precisely balanced in order for the bird to stabilize in the air. It’s believed that tail fanning allows hummingbirds to remain properly oriented during hovering and adjust their flight alignment as needed.

When flying forward quickly or changing direction, hummingbirds will fan their tails to counteract destabilizing torque. The tail essentially acts as a rudder to allow precision control while the wings provide lift and thrust. Even slight tail adjustments aid hummingbirds in maintaining optimal positioning as they feed or compete for territory.

Drawing Attention to Flowers

There is some evidence that hummingbirds flare their tails upon arriving at a flower to attract other pollinators. The sudden flash of color could alert bees or butterflies to the flower’s location and the presence of nectar. This helps promote more plant fertilization.

Research with Anna’s hummingbirds showed they fanned their tails more often after inserting their bills into a flower compared to when moving between flowers. It’s speculated the tail flairing makes the flowers more conspicuous to nearby pollinators also foraging in the area. This behavior could be an inadvertent result of communicating to rivals that a food source is taken.

Differences Based on Species, Age, and Sex

While all hummingbirds use tail flaring to some degree, there are some differences between species, ages, and sexes when it comes to fanning their tails:

Species Differences

Some hummingbird species are known to flair their tails much more aggressively including Anna’s, Allen’s, Rufous, and Costa’s hummingbirds. More mild-mannered species like Calliope and Broad-tailed hummingbirds aren’t as prone to exaggerated tail motions.

The Buff-bellied hummingbird has one of the widest tail feathers with a distinct rounded shape that makes its tail fanning highly noticeable. The Scissor-tailed hummingbird’s exceptionally long tail feathers add acrobatic dimensions to its tail flairing capabilities.

Age Differences

Younger hummingbirds are still perfecting the muscle control and coordination required to accurately fan their tails. Their flairing will be much less pronounced and consistent compared to mature adults. Fledglings may pump or shake their tails haphazardly trying to emulate mature fanning.

Sex Differences

As mentioned previously, male hummingbirds tend to flare their tails much more frequently in a broader range of contexts than females. This includes aggressiveness, courtship dancing, alarming other birds away from food sources, and releasing excess heat while feeding.

However, female hummingbirds will also fan their tails as a mating solicitation to males and occasionally to ward off other females from their territory or food source. In general though, the males do the majority of the communicating through pronounced tail flairing.

Tail Flaring Motions

Hummingbird tails are incredible flexible with specialized vertebrae that allow them to move in almost any direction. The actual fanning motion can take many different forms including:


This is the most common tail flaring method. The hummingbird rapidly moves its tail sideways back and forth like a fan. The degree of flairing may only be a few inches or as much as 180 degrees in very exaggerated displays. The tail remains in the same horizontal plane as the body.

Up and Down

Sometimes hummingbirds will flap their tails vertically up and down instead of side-to-side. This fanning pattern tends to be more pronounced with a larger range of motion extending from pointing the tail down below the body to flicking it straight up over the back.


In this motion, the hummingbird fans its tail along an oval or circular path with the tail revolving around its base to create a full pivoting circle. Instead of just flicking left and right, the tail describes a complete revolution.


At other times, hummingbirds may vibrate or shiver their tails very rapidly without much side-to-side or up-and-down motion. It manifests as a very fast buzzing or shaking action. This occurs in short bursts and may serve as a low-level warning.


With this showy fanning display, the hummingbird moves its tail in a horizontal figure-eight or infinity loop pattern by combining circular pivoting and side-to-side motions. The tail traces stylized loops to form the shape of an 8.


In some cases, hummingbirds will only flare one side of the tail, keeping the other side motionless. This may help with torque balance during flight or draw attention to a particular direction during displays. One-sided fanning provides nuance and variation.

Tail Feather Characteristics

The tail feathers, or rectrices, of hummingbirds have evolved special physical adaptations that allow them to be flared so rapidly without causing damage:

Thin and Narrow Shape

Hummingbird tail feathers have an extremely slim, tapered shape that provides aerodynamic efficiency and reduces air resistance during fanning motions. This allows the tail to be moved faster with less exertion.

Lightweight Construction

The feathers are composed of lightweight keratin and have thin rachises or central shafts. This minimizes the mass being flapped and decreases inertial forces for quicker movements.

Dense Specialized Barbule Hooks

While hummingbird feathers are tiny and fine, they have dense, specialized microscopic hooks called barbules that zip adjacent barbs tightly together to provide strength and prevent the feather vanes from fraying during vigorous fanning motions.

Flexible Attachment to Tail Bones

The hummingbird’s tail vertebrae and musculature allow great range of motion for the tail feathers. Loose, flexible attachments at the base let the feathers pivot and flare freely.

Short Rigid Base

The inner base of the tail feathers are made of a short, hardened, somewhat flattened section that provides stability and support right next to the skin where airflow forces are most intense during fanning.

Muscles Used for Tail Flaring

Flaring their tails with such speed, agility, and control requires hummingbirds to use specialized muscles:

Pygostyle Muscles

The basal fulcral muscles attach to a pygostyle bone at the tail tip and allow up and down or side-to-side motions. They provide the force for fanning.

Spreading Muscles

Paired spreading muscles run along either side of the top of the tail and pull the feathers apart, opening the tail into a fan.


Depressor muscles on the underside of the tail pull the tail downwards as needed during fanning.


Levator muscles on the back of the tail raise the tail up when flaring.

Preen Gland Muscle

This muscle compresses the preen gland to secrete oil that helps condition the tail feathers and prevent wear.

Why Tail Flaring Is Essential for Hummingbirds

While small, the tail of a hummingbird plays a remarkably important role in their behavior and biology:

Visual Communication

The fantastic range of motions, colors, and patterns allow hummingbirds to communicate extensively through tail flaring displays. This non-contact signaling is vital to mating, territoriality, and resolving conflicts.

In-Flight Stability

Subtle tail adjustments provide essential aerodynamic stability and steering as hummingbirds hover and dart around. The tail acts as a rudder to compensate for the lift forces from the wings.

Behavior Regulation

By flaring their tail, a hummingbird can instantly signal changes in disposition – from aggression, to courtship, to alarm. Other birds can react accordingly and adjust their own behavior.


The constant fanning action helps release surplus heat generated by hummingbirds’ incredibly fast metabolism and prevents overheating.

Energy Efficiency

Specialized tail feathers and muscles allow flaring with minimal energy expenditure, important for these tiny birds with high caloric needs.

So in summary, hummingbirds flare their tails for mating displays, conveying aggression, stabilizing flight, dissipating excess heat, and potentially drawing pollinators to flowers. The tail is an essential, multi-purpose communication and control device for hummingbirds, allowing them to quickly signal intentions and maintain aerial agility. Next time you see a hovering hummingbird, pay close attention to how it uses delicate tail motions to speak volumes.

Hummingbird Species Typical Tail Flaring Behavior
Anna’s Hummingbird Extensive flaring, figure-eight motions, high aggression displays
Allen’s Hummingbird Frequent flaring, wide side-to-side motions, moderately aggressive
Calliope Hummingbird Occasional flaring, subtle motions, less aggressive
Broad-tailed Hummingbird Infrequent flaring, simple up-and-down motions, less aggressive
Rufous Hummingbird Constant flaring, complex patterns, highly aggressive


Hummingbirds’ remarkable flying talents are supported by the versatile, articulated tail that acts as a communications beacon, aerodynamic rudder, and critical thermoregulator. The characteristic fanning motions help hummingbirds efficiently navigate their fast-paced, hovering lifestyle. So next time you notice a hummingbird rapidly flicking its bright feathers, you’ll understand just how essential tail flaring is for these aerial masters.

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