Many people are fascinated by hummingbirds and their incredible ability to hover and fly backwards. But is it really true that they can fly backwards? The short answer is yes, hummingbirds are capable of flying backwards. However, there are some caveats to this ability that are worth exploring in more detail.
Anatomy that Allows Backwards Flight
Hummingbirds have specialized anatomy that enables them to fly both forward and backwards. Their wings are able to rotate in a full 180 degree arc, allowing the wing motion used for forward flight to be reversed, providing thrust in the opposite direction.
| Wing Feature | Description |
| Full 180 Degree Arc | Hummingbird wings can rotate fully backwards and forwards, enabling reversed wing thrust. |
| High Wingbeat Rate | Hummingbird wings beat up to 80 times per second, generating significant backwards thrust when reversed. |
| Leading Edge Feathers | Specialized feathers on the wing’s leading edge are critical for generating lift during backwards flight. |
In addition, their high wingbeat frequency, up to 80 beats per second, provides substantial thrust in either direction when the wing motion is reversed. The specialized feathers on the leading edges of their wings, known as stiff-shafted feathers, are also essential for maintaining lift during backwards flight. Without these anatomical adaptions, hummingbirds would not possess their unique flight abilities.
Backwards Hovering and Flight
Many species of hummingbirds are capable of sustained backwards hovering. During backwards hovering, the wings continuously generate reversed thrust to counteract the bird’s weight and maintain position. This allows hummingbirds to hover in place even when facing tail-first. Backwards flight, similarly, involves generating reversed wing thrust to propel the bird backwards, with typical speeds of 5-7 meters per second being reported.
Some key facts about backwards flight in hummingbirds:
- Ruby-throated hummingbirds can sustain backwards hovering for up to 10 seconds.
- Backwards flight is typically used for short distances, less than 10 meters.
- Giant hummingbirds appear to be the only species incapable of backwards flight.
- Flying backwards expends more energy than forward flight in hummingbirds.
Researchers have investigated exactly how hummingbirds coordinate their aerodynamics and stability during backwards flight. High speed video has revealed that their tail feathers play a key stabilizing role, adjusting feather angles to maintain smooth flight. Slow motion footage has also provided insight into the precise wing motion used during backwards flight.
When and Why Hummingbirds Fly Backwards
Hummingbirds use their unique ability to fly backwards for specific purposes:
While Feeding
Backwards flight allows hummingbirds to maintain access to nectar while feeding. As they lick nectar up to 13 times per second, they can use brief backwards bursts to keep position at each lick. This prevents them having to repeatedly switch between forward and hovering thrust.
During Courtship Displays
Male hummingbirds perform elaborate courtship displays for females, flying in a range of patterns. Backwards loops and dives allow them to maintain visual contact with potential mates during these displays.
Escaping Danger
When startled or threatened, hummingbirds will rapidly flip their direction using backwards flight to escape. Being able to see the threat while retreating offers them safety.
Intimidating Opponents
Backwards charges are sometimes used against competing hummingbirds, surprising opponents and potentially forcing them to retreat from a food source. The sudden backwards attack also allows them to keep watch on their opponent.
High Speed Maneuvers
Backwards motions can be incorporated into fast aerobatic maneuvers such as rapid ascents, rolls and dives. The additional maneuverability provides a broader range of flight capabilities.
Differences Between Species
Most hummingbird species exhibit some capacity for backwards flight. However, certain large hummingbird species appear incapable of sustained backwards flight. For example:
- Giant hummingbirds – Weighing up to 24 grams, these birds are likely too heavy to sustain backwards flight.
- Wedge-tailed sabrewings – Their larger size and up to 10cm wingspan suggests limited reverse flight ability.
- White-necked Jacobin – Their long tails may prevent the stability required for backwards flight.
In contrast, smaller hummingbird species perform backwards flight with great agility:
- Bee hummingbird – The world’s smallest bird at 2 grams has remarkably precise control in backwards flight.
- Anna’s hummingbird – Their impressive courtship displays incorporate sustained and rapid backwards dives.
- Ruby-throated hummingbird – Skilled at precisely holding position while licking nectar when feeding.
Energetics of Backwards Flight
Backwards flight in hummingbirds is more energetically demanding than forward flight at the same speed. The metabolic cost can be up to 30% higher in backwards flight. There are several explanations hypothesized:
- Inefficient Reversed Wing Motion – The reversed orientation of backward flapping may be inherently less efficient.
- More Stabilization Required – Additional energy is needed for tail and wing adjustments to maintain control.
- Unnatural Posture – The posture and center of mass may be suboptimal in backwards orientation.
Due to the greater energy demands, hummingbirds limit the time spent in backwards flight during activities like feeding and courtship displays. Sustained backwards flight for long durations would require very high energy consumption. This could limit the bird’s energy budget for essentials like breeding and avoiding predators.
Unique Flight Adaptions
Hummingbird flight in all directions relies on unique anatomical adaptions not found in other birds:
- Extremely Lightweight – Hummingbird bones are minimalistic, with some hollow regions, reducing weight.
- Rotatable Wrists – Wrist joints allow wing rotation through a full 180 degrees range of motion.
- Reduced Number of Tail Feathers – Only 10, rather than 12-24 tail feathers, minimizing weight.
- Stabilizing Tail Shape – The forked tail provides stability and control during hovering and rapid maneuvers.
- Concentrated Chest Muscles – Proportionally enormous flight muscles comprise up to 30% of their total body weight.
These specialized adaptations allow hummingbirds to perform their signature hovering ability, as well as provide thrust and control in all directions.
Conclusions
In summary, hummingbirds are truly unique in their ability to fly both forward and backwards due to evolutionary adaptations such as 180 degree wing rotation and a stabilized tail. While backwards flight is more metabolically costly, they utilize it skillfully for feeding, territorial disputes, courtship displays, and evading threats. Next time you observe a hummingbird rapidly change direction, you can marvel at this feat only possible due to the hummingbird’s remarkable evolutionary innovations. Their distinctive flight capabilities will likely continue to make the hummingbird a favorite and captivating bird for nature enthusiasts.
