Hummingbirds are one of the most fascinating birds in the world. Their speed, agility, and unique adaptations capture people’s imaginations. With over 300 different species, hummingbirds display an incredible diversity in size, color, behavior, habitat, and geographical distribution. Their rapid wing beats and ability to hover set them apart from all other birds. But which facts about these remarkable creatures are true and which are myths?
Hummingbirds Have Very High Metabolism
It is true that hummingbirds have an incredibly fast metabolism compared to other animals. Their hearts can beat up to 1,260 times per minute and they take approximately 250 breaths per minute while at rest. This rapid metabolism is needed to support their fast-beating wings and allows them to burn through calories quickly as they feed on flower nectar throughout the day. Their high metabolism requires that they consume more than their body weight in nectar each day, sometimes visiting over 1,000 flowers per day and eating up to 8 times per hour to get enough calories. The speed at which they process energy is the fastest of any vertebrate animal.
Hummingbirds Hover in Mid-air
The ability to hover in mid-air sets hummingbirds apart from other birds and even insects. They are the only birds that can fly backwards and upside down. Hovering allows them to maintain a fixed position relative to flowers as they extract nectar, rather than having to land repeatedly. Their specially adapted wings permit them to beat up to 200 times per second, creating the lift required to hover. The angle and position of their wings changes during each phase of the wingbeat to maximize hovering stability. Certain species like the Bee Hummingbird can even hover in a strong wind, an incredibly challenging feat of aerodynamics and muscle control.
Hummingbirds Have No Sense of Smell
It was previously thought that hummingbirds could not smell and relied solely on vision to find food sources. However, recent research indicates that they do indeed have a functioning sense of smell and can detect scents while foraging. Scientists trained hummingbirds to detect food scents in experiments and the birds learned to associate specific scents with food rewards. Their sense of smell likely plays an important role in seeking out nectar sources. However, vision remains their dominant sensory modality as they rely on color vision to locate flowers while feeding.
Hummingbirds Only Eat Nectar
While nectar from flowering plants is the primary food source for hummingbirds, they do not eat only nectar. Hummingbirds have a diet that also consists of small insects such as fruit flies, spiders, aphids and gnats. The protein from eating insects likely provides important nutrients lacking in nectar. Female hummingbirds that are producing eggs in particular require the extra protein. This shows that hummingbirds have a varied diet and exploit other food sources besides high-energy nectar. In fact, it is estimated that insects may make up 5-30% of their overall food intake depending on the species.
Hummingbirds Migrate Long Distances
It is true that some species of hummingbirds embark on incredible migrations covering thousands of miles. Ruby-throated hummingbirds travel from Canada and the eastern United States to southern Mexico and Central America each fall. Rufous hummingbirds migrate from Alaska and Canada down to Mexico for the winter months. These tiny birds fly nonstop over the Gulf of Mexico, a 500 mile journey requiring up to 24 hours of continuous flight over open water. Their fat stores and metabolism provide enough energy to sustain these marathon trips. However, not all hummingbird species migrate. Tropical species often remain year-round in their breeding habitat.
Hummingbirds Live Only on Flower Nectar
This is false – hummingbirds get most, but not all, of their nutrition from flower nectar. While they have anatomical adaptations for nectar-feeding, including long, slender beaks and tongue tubes that allow them to access nectar, they also eat insects for essential protein and nutrients. Male hummingbirds may allow females priority access to nectar sources, instead catching more insects to supply their nutritional needs. Baby hummingbirds are fed insects by their mothers early on, not nectar, to support growth and development. So while hummingbirds certainly rely on nectar, they supplement their diet with insects and have varied nutritional needs beyond just sugar water.
Hummingbirds Help Pollinate Plants
It is true that hummingbirds play an important ecological role as pollinators for many plant species. As hummingbirds visit flowers to drink nectar, pollen sticks to their head, bill, throat, and feathers. This pollen is then transferred to the next flower they visit, pollinating the plant. Some plant species rely on hummingbirds as their primary or exclusive pollinator, shaping the mutualistic relationship between plants and hummingbirds over evolutionary time. These plants have nectar specially adapted to hummingbird pollination. Hummingbirds favor red tubular flowers, unlike most insect pollinators. Their hovering ability allows them to access nectar from flowers in hard to reach places.
Hummingbirds Have No Sense of Taste
This myth about hummingbirds is false – in fact, they have fairly well-developed taste perception. Experiments where different concentrations and types of sugars were added to nectar showed that hummingbirds can differentiate tastes and prefer higher sugar nectar with some added electrolytes. They use taste to assess food quality while foraging. Their taste buds are located on the tip of the tongue and may be specially adapted to detect sweetness in nectar. Hummingbirds even extend their tongues fully in nectar before ingesting it, suggesting they may sample tastes prior to drinking. So while we are still learning about hummingbird physiology, evidence indicates taste is one of their senses.
Hummingbird Nests Are Fragile
Hummingbird nests may appear delicate given their tiny size, but they are actually durable, resilient structures. The nest is made of plant down wrapped together with strands of spider silk and sometimes held together with pine resin. This makes the nest expandable and able to endure stretching as the young hummingbirds grow. Nests are often built tightly wedged into branches, bound to the limbs with spider silk to provide stability. Female hummingbirds may decorate the outside with lichen or moss as camouflage. The closely woven silk allows the nest to expand to double its size without breaking. So hummingbird nest architecture is remarkably strong for its miniature form.
Hummingbirds Hibernate
Hummingbirds do not hibernate, which involves entering a prolonged deep sleep. This myth developed because hummingbirds disappear from their breeding grounds in North America during winter months. However, they have not gone into hibernation, but instead migrated long distances to warmer climates in Mexico, Central America, and the Caribbean. Their high metabolism prevents them from going into torpor or a hibernation-like state. Even on cold nights, they increase their metabolism to survive. The absence of flowering plants and nectar in their breeding habitat forces them to migrate to find food. But they remain active and cannot hibernate through winter due to their extreme metabolic demands.
Male and Female Hummingbirds Look Identical
In the majority of hummingbird species, the males and females have distinct plumage differences. Adult male hummingbirds are known for their bright, iridescent throat feathers, called a gorget. Females lack this colorful throat patch or have more muted plumage in that area. For example, male Anna’s hummingbirds have a rose-red throat and iridescent green back, while females have grey-green plumage on top and grey throat with some red spotting. However, female hummingbird plumage can still display unique color patterns, like the cinnamon tail of female Costa’s hummingbirds. Juvenile birds resemble adult females until they molt into their species-specific adult male plumage.
Hummingbirds Have UV Color Vision
Recent research suggests that hummingbirds can see into the ultraviolet (UV) spectrum, unlike humans who cannot see UV. Their eyes contain a fourth cone type sensitive to UV wavelengths that may help them find nectar guides on flowers. These nectar guides are patterns on petals visible in UV that point the way to nectar sources like landing lights on a runway. Hummingbird-pollinated flowers often have UV patterns along with red coloration. The ability to see UV may help hummingbirds discern these markings and forage more efficiently. Hummingbird vision is specialized to detect flower colors, including wavelengths into the near UV range.
Hummingbirds Have No Sense of Hearing
While not as well-studied as their other senses, hummingbirds do have a sense of hearing and can perceive sounds. They produce vocalizations during courtship and communication using harmonically rich chirps and whistles. Their ears have a narrow range of optimal hearing at frequencies relevant to conspecific vocalizations. Hummingbirds may also hear ultrasonic echolocation calls made by bats, prompting avoidance behavior when bats are hunting nearby. Their hearing appears adapted for communication, mating, and predator cues rather than noise detection over a wide frequency range. So hummingbirds can hear vital sounds in their environment, contrary to the myth.
Hummingbirds Never Stop Flying
It is not true that hummingbirds stay continuously airborne. They cannot sleep or rest on the wing and must stop flying to conserve energy at times. At night, hummingbirds enter a hibernation-like state called torpor where their metabolic rate and body temperature drops to conserve energy. Their heart rate slows to 50-180 beats per minute and they become lethargic and inactive. By slowing their metabolism by 50-95%, torpor enables hummingbirds to survive cold temperatures and limited food availability. Torpor can last up to 12 hours overnight. So hummingbirds cannot fly continuously around the clock and must rest and recharge.
Hummingbirds Have Exceptional Memories
Research shows that hummingbirds have excellent long-term memories and recall specific locations, solving complex spatial memory tasks. When hummingbirds feed, they remember which individual flowers they have previously visited and will avoid them to seek out flowers with renewed nectar. This minimizes revisiting emptied flowers and makes their foraging more efficient. They can remember locations over timescales of days, indicating an impressive cognitive map and memory capacity. Female hummingbirds may also remember favorable nesting spots year after year. Given their small size, their navigational skills and spatial memory are striking.
Hummingbirds Can Survive Freezing Temperatures
Hummingbirds have an amazing physiological adaptation that allows them to survive freezing overnight temperatures in their habitats. By lowering their body temperature and entering a state of torpor, their breathing and heartbeat slows, reducing their metabolic rate by 95%. This enables them to conserve energy when food sources are not available. Their body temperature can drop remarkably low, to the point where they are able to withstand some degree of freezing. There are documented cases of hummingbirds thawing after their body temperature reached below freezing. This unique physiological adaptation enables their survival in cold climates.
Hummingbirds Use Spider Silk for Their Nests
This is a somewhat surprising fact that happens to be true. Hummingbird nests are constructed primarily from soft plant down, but hummingbirds weave the down together using strands of spider silk, which constitutes 10% or more of the nest material. Spider silk is five times stronger than a comparable piece of steel, so it creates a durable, flexible outer layer to protect the nest. Female hummingbirds scrape spider silk off of webs with their bills and feet to collect it for nest building. The silk allows the nest to stretch as young birds grow inside it without collapsing. Spider silk provides crucial structural support.
Conclusion
Hummingbirds are some of the most fascinating avian creatures, capturing our imaginations with their speed, aerobatics, and magical hovering ability. Examining common myths and facts about these birds reveals important insights into their physiology, ecology, behavior, and survival adaptations. Their rapid metabolism, sugar-rich diet from nectar, migration needs, torpor ability, spatial memory, and use of spider silk highlight just some of the many remarkable qualities of hummingbirds. They are beautiful pollinators to watch and study, and many mysteries still remain about these captivating creatures. Careful scientific observation helps illuminate reality from myth and deepens our understanding and appreciation of their biological uniqueness.
