Hummingbirds are small, colorful birds that are found exclusively in the Americas. Here are some key facts about hummingbirds:
– They are the smallest birds in the world, with most species measuring just 3-5 inches in length. The bee hummingbird is the smallest at only 2.25 inches long.
– They have long slender bills that are adapted for accessing nectar from flowers. Their tongues are also specially adapted to lap up nectar.
– Hummingbirds have very fast metabolisms and rapid heart rates in order to power their constant motion. Their hearts can beat up to 1,260 beats per minute.
– They can flap their wings up to 80 times per second, allowing them to hover in place as well as fly forwards, backwards, up, down, and sideways. This allows them to access flower nectar that other birds can’t.
– Many hummingbird species migrate long distances each year. For their size, they make one of the most impressive migration journeys in the animal kingdom.
– There are over 300 species of hummingbirds found in a variety of habitats from rainforests to mountains to deserts. They occupy a niche role as pollinators.
Physical Characteristics
Hummingbirds are very small birds with compact, slender bodies and long tails and beaks relative to their overall size. Here are some more details on their physical characteristics:
Size
As mentioned earlier, hummingbirds are the smallest birds in the world. Their minuscule size allows them to hover in place at flowers as they drink nectar. The smallest species is the bee hummingbird which is only 2.25 inches long and weighs less than 2 grams. In comparison, the largest hummingbird species – the giant hummingbird – is 8.5 inches long with a 5 inch wingspan and can weigh up to 24 grams. Most other hummingbirds fall somewhere in between at 3 to 5 inches long.
Bills
One of the most distinguishing features of hummingbirds is their long slender bill which can be straight, curved, or slightly bent. Their bills evolved to allow them to access nectar at the base of tube-shaped flowers. When not in use, they have the ability to lock their bills in place to conserve energy. The sword-billed hummingbird has the most dramatic bill at 4 inches long – longer than its body! This allows it to feed on nectar from flowers with very long corollas.
Wings
Hummingbirds have short broad wings that enable them to flap at high frequencies. As their main means of locomotion, hummingbirds’ wings allow them to fly forwards, backwards, laterally, hover in place, and even invert their bodies while in flight. Their specialized shoulder joints allow their wings to rotate in a full circle. Most hummingbird species flap their wings 12-80 times per second.
Tails
Hummingbirds also have short tails relative to their body length. Their forked or notched tails provide stability and maneuverability in flight. Specific tail shapes vary by species and the differences can be used to identify them.
Feathers
Hummingbirds have compact, dense plumage covering their entire bodies except their beaks and feet. The feathers over their wings are structured to minimize drag during the downstroke while maximizing lift during the upstroke. Most hummingbirds have bright, iridescent throat or crown feathers that appear to change color in different lighting. Males and females often have different color patterns. Molting happens once or twice per year.
Skeleton
Hummingbirds have a specialized lightweight skeleton to minimize their overall mass. Many of their bones are hollow with thin outer bone layers. They have fewer vertebrae and fused foot bones compared to other birds. Their unique shoulder structure allows the 360 degree rotation of their wings. Strong muscle attachments provide the power needed for sustained hovering and rapid flight.
Behavior and Diet
Hummingbirds exhibit very characteristic energetic behavior tied to their high metabolic needs. Their diet consists almost solely of sugary nectar and insects.
High Energy Lifestyle
Hummingbirds have extremely high metabolism and oxygen needs related to hovering flight. At rest, their heart rate can be 500 beats per minute, going up to 1,260 bpm during flight. Their breathing and heart rate are synchronized so that oxygen-rich blood reaches their muscles as they contract. Even at rest they may breathe 250-300 times per minute.
To power their metabolically taxing lifestyle, hummingbirds need to consume a large amount of sugars. They obtain this primarily from flower nectar and tree sap which are composed mainly of sugars and water. Hummingbirds are continuously hours away from starving, so they forage actively whenever they are awake.
Diet – Nectar
Flower nectar provides the high-energy sugars that hummingbirds rely on. Their diet consists of 25% sugar, making them the most carbohydrate-consuming birds. Hummingbirds can lick nectar up to 13 times per second due to their specialized tongue structure. They prefer red tubular flowers, but will feed from a variety of flower shapes and colors.
Hummingbirds do not suck nectar through their narrow bills, but instead use capillary action and licking to draw nectar into their mouths. When feeding, they will lick at a rate of licks per second matching a flower’s nectar refill rate, thus maximizing energy intake.
Diet – Insects
In addition to nectar, hummingbirds get essential proteins, vitamins, minerals, fats, and amino acids from consuming insects. They prey on insects like fruit flies, gnats, aphids, spiders, caterpillars and small bees. Hummingbirds may eat hundreds of tiny insects per day representing 5-10% of their diet.
Behavior Adaptations
Many aspects of hummingbird behavior relate to accommodating their high metabolic lifestyle:
– Aggressive territoriality – hummingbirds aggressively guard flower territories and nectar sources.
– Impaling insects – they will impale tiny insects on thorns or bark to save for later consumption.
– Torpor – hummingbirds can enter a temporary hibernation-like state to conserve energy overnight or in poor weather conditions. Their temperature and metabolism slows down and heart rate drops to 50-180 bpm.
– Sunbathing – hummingbirds sunbathe in the mornings to raise their body temperature before becoming active.
– Rainbathing – hummingbirds will flatten their feathers and expose their skin to rain showers to remove excess heat.
Reproduction and Lifecycle
Hummingbirds have an accelerated reproductive cycle compared to other birds due to their frenetic lifestyle and high metabolism. Here are some key aspects of how they mate and raise young:
Courtship
Most hummingbird courtship occurs in flight. Males will perform elaborate aerial displays, flying in loops and dives to impress females. Colorful iridescent plumage and vocal songs also play a role attracting mates. Once paired, couples may perch together between mating sessions, but the male does not assist with nesting or raising young.
Nests
The female alone builds a tiny compact cup-shaped nest out of plant down, spider webs, lichens and moss. Nests are only about 2 inches wide and may be cleverly disguised on a tree branch or hidden structure. Hummingbird eggs are the smallest of all birds at the size of a coffee bean.
Eggs
Hummingbirds lay two pea-sized eggs per reproductive cycle. The eggs are white without speckles or markings. Incubation until hatching takes 14-23 days depending on climate and altitude. The mother incubates the eggs, sitting on the nest up to 75% of daylight hours.
Babies
Hummingbird chicks hatch naked and blind, weighing only 0.6 grams. They develop quickly though, doubling their weight in one day. By 9-12 days old, they open their eyes and grow proper feathers for flight. After 3 weeks, the young hummingbirds are ready to fledge from the nest.
Fledglings
For the first few days after leaving the nest, fledgling hummingbirds need to rest and gain skills. They can initially only fly short distances and rely on their mother for food. Within a week, they become fully independent. Some migrate long distances within months of fledging.
Lifespan
In the wild, most hummingbirds live 3-12 years depending on the species. The average lifespan is 5 years. In captivity, the longest living hummingbird reached 12 years of age. Threats in nature include predators, disease, weather, starvation and loss of habitat.
Migration
One of the most astonishing facts about hummingbirds is their incredible migration each year given their tiny body size. Here are key details on their migration habits:
Distance
Depending on the species, hummingbirds migrate 500 to over 5,000 miles each way over ocean and desert. For their size, this is the longest migration of any bird in the world in relation to body length. The rufous hummingbird migrates a remarkable 3000 miles each way between Alaska and Mexico.
Navigation
It’s still somewhat a mystery how these tiny birds can find their way over such immense distances. Research suggests they orient themselves using the sun’s position and geomagnetic fields. They appear to have an internal magnetic compass and spatial mapping system passed on through genetics and learning.
Timing
Most hummingbirds migrate in the spring and fall depending on food availability in their breeding grounds. Ruby-throated hummingbirds fly 500 miles nonstop over the Gulf of Mexico in a 25 hour journey. Western species migrate down the Pacific coast and through central America stopping to refuel along the way.
Preparation
Before migrating, hummingbirds enter hyperphagia, nearly doubling their weight by storing extra fat for the energy needed. They also conserved muscle mass and shrink digestive organs adaptively. Young hummingbirds setting out for the first time somehow know the correct migratory route to follow without guidance.
Hazards
Hummingbirds face many threats during migration including exhaustion, starvation, predators, storms, collisions with buildings or cars, habitat loss, and climate change altering food sources. Urban lighting and noise pollution can disorient them. As many as half do not complete migration journeys.
Threats and Conservation
While hummingbirds exist solely in the Americas, some species are under threat from human impacts on their habitats and food sources. Conservation measures can help protect them.
Habitat Loss
Land clearing and development removes hummingbird habitat including forests, meadows and flower gardens. Pesticide use also reduces their insect prey. As urbanization expands, hummingbirds lose nesting sites and nectar sources.
Climate Change
Flower blooming cycles are shifting earlier in spring with warming temperatures, disrupting hummingbirds’ seasonal migration timing and ability to access food. Some species have declined by up to 90% in the last century.
Collisions
Hummingbirds become disoriented by human structures. They can collide into windows or get trapped inside greenhouses. Wind turbines and cars also kill many birds during migrations. Outdoor cats prey on thousands of fledglings each year.
Disease
Bacterial, viral and fungal illnesses can rapidly spread and kill hummingbirds that congregate at feeders. Providing clean nectar and isolating sick birds reduces infection risks. Climate change aids spread of diseases.
How to Help
Here are some ways you can help protect hummingbirds:
– Provide nectar feeders especially during migration months
– Plant native nectar flowers and milkweed for butterflies
– Install screens on windows/greenhouses
– Keep cats indoors
– Support habitat conservation organizations
– Reduce pesticide and herbicide use
– Get involved in citizen science monitoring programs
Unique Species
With over 300 species, hummingbirds display incredible diversity. Here are some noteworthy species:
| Species | Description |
|---|---|
| Bee Hummingbird | The world’s smallest bird at 2.25 inches long found in Cuba. |
| Anna’s Hummingbird | One of 4 species found in the USA. Males make aerial dive displays. |
| Ruby-Throated Hummingbird | Migrates over the Gulf of Mexico. Males have bright red throats. |
| Rufous Hummingbird | One of the farthest migrating species at 3000 miles each way. |
| Sword-Billed Hummingbird | Unusual 4 inch bill adapted for a specific nectar flower. |
| Giant Hummingbird | Largest species with 8.5 inch body and 5 inch wingspan. |
Conclusion
In summary, hummingbirds are spectacular tiny birds uniquely adapted to hovering flight, nectar feeding, and migrating immense distances. Their high energy lifestyle and dazzling iridescent colors make them a favorite backyard visitor. While some species are declining, we can help protect them by providing food sources and diminishing threats. Hummingbirds serve an important role as pollinators in American ecosystems. Their remarkable characteristics continue to fascinate ornithologists and nature lovers alike. With ongoing conservation efforts, these energetic creatures will hopefully continue thriving for centuries to come.
