The ruby-throated hummingbird (Archilochus colubris) is a small hummingbird that is the only breeding hummingbird in eastern North America. Ruby-throated hummingbirds are known for their iridescent emerald or ruby-red throat patch (depending on the angle of light) and their distinctive buzzing wingbeats. They are classified in the order Apodiformes, family Trochilidae, and genus Archilochus.
Taxonomy
The ruby-throated hummingbird’s scientific name is Archilochus colubris. Breaking this name down:
- Archilochus – The hummingbird genus, first described in 1827 by French zoologist Charles Lucien Bonaparte.
- colubris – The specific epithet, which is Latin for “snake” or “serpent.” This refers to the bird’s slim shape and long bill.
So the full scientific name Archilochus colubris translates to “snake-like Archilochus.”
In terms of taxonomy and classification, the ruby-throated hummingbird belongs to:
- Kingdom: Animalia (animals)
- Phylum: Chordata (vertebrates)
- Class: Aves (birds)
- Order: Apodiformes (swifts and hummingbirds)
- Family: Trochilidae (hummingbirds)
- Genus: Archilochus
- Species: A. colubris
There are over 300 different species of hummingbirds in the Trochilidae family. The Archilochus genus includes only one other species besides the ruby-throated hummingbird: the black-chinned hummingbird (Archilochus alexandri) of western North America. These two Archilochus species are very closely related.
Physical Characteristics
The ruby-throated hummingbird is North America’s smallest breeding bird. Some key physical features include:
- Size – Adults measure 2.75-3.5 inches long with a 3.5-4.3 inch wingspan.
- Bill – Long, thin bill that is slightly downcurved.
- Plumage – Males have metallic green upperparts, clean white underparts, and a distinctive ruby-red throat. Females lack the red throat patch and are pale brownish-white underneath with green spots on the flanks.
- Tail – Deeply forked tail feathers.
- Legs and feet – Small with weak legs and tiny feet used mainly for perching rather than walking or hopping.
- Flight – Hummingbirds have uniquely structured wings that allow them to hover in place and fly forwards, backwards, up, down, and upside down.
Some key adaptations that allow ruby-throated hummingbirds to hover and fly swiftly include:
- Wings – Short, rounded wings that can beat up to 70 times per second.
- Lightweight skeleton – Weighing around 3 grams, about the same as a penny.
- Flight muscles – Make up 25-30% of their total body weight. Other birds’ flight muscles are 15-20% of total weight.
- Rotating shoulders – Allow their wings to move in a full circular motion.
- Tiltable wrists – Let them change the angle of their wings as needed for agile flight.
In terms of size, ruby-throated hummingbirds are considered medium-small compared to other hummingbird species. The bee hummingbird is the smallest at just 2 inches long. Larger hummingbird species can reach up to 8.5 inches in length. But despite its diminutive stature, the ruby-throated hummingbird migrates remarkably long distances.
Habitat and Range
During summer breeding months, ruby-throated hummingbirds are found across most of eastern North America. Their breeding range extends:
- North – Into southeastern Canada including southern Ontario, Quebec, New Brunswick, and Nova Scotia.
- South – Along the U.S. Atlantic coast to Florida and Gulf coast to eastern Texas.
- West – To the eastern edges of North Dakota, South Dakota, Nebraska, Kansas, Oklahoma and Texas.
Within this broad range, preferred summer habitats provide:
- Flowering plants – For accessing nectar. Open areas near forests/woodlands or meadows are ideal.
- Water – Nearby water sources such as streams, ponds, etc.
- Old trees – Dead snags or branches for nesting spots.
- Brush – Low shrubs and tree saplings provide cover and perches.
During winter months, almost the entire North American ruby-throated hummingbird population migrates to Central America and Mexico. Their winter range includes:
- Mexico
- Belize
- Guatemala
- El Salvador
- Honduras
- Nicaragua
- Costa Rica
- Panama
In their winter grounds, ruby-throated hummingbirds prefer tropical secondary forests, woodland edges, semi-open habitats with flowers, and parks or gardens.
This extensive migration covers 3,000-5,000 miles roundtrip every spring and fall. Ruby-throated hummingbirds migrate north earlier than most other North American birds, usually arriving on breeding grounds by April or May.
Diet and Feeding
Like all hummingbirds, ruby-throated hummingbirds subsist primarily on sugary flower nectar and tree sap. They have specialized tubular tongues perfectly adapted for lapping up liquid.
Some key facts about ruby-throated hummingbird diet and feeding:
- Nectar – Provides carbohydrates. Favorite flower sources include columbine, trumpet vine, jewelweed, bee balm, and red buckeye.
- Tree sap – An important food source especially early spring before flowers bloom.
- Small insects – Provide protein, captured from flowers, leaves, bark crevices, spiderwebs, etc. Mayflies, flies, aphids, and leafhoppers are common prey.
- Sugar water – Commonly fed by people through nectar feeders with sucrose formulas 4:1 ratio sugar:water.
- Laps 10-20 times per second – Using a specially adapted, forked tongue to collect nectar.
- Eats half its weight daily – Requires frequent feeds every 10-15 minutes given tiny stomach size.
- Does not suck nectar – contrary to belief, hummingbirds use their tongue as a tiny pump to lap nectar.
- Skilled aerialists – Can precisely hover and access flower nectar unattainable to other pollinators.
- Important pollinators – While feeding, ruby-throats transfer pollen on their head and bill.
To conserve energy, ruby-throated hummingbirds go into a state of torpor at night by lowering their body temperature and metabolic rate. This torpor allows them to survive cold nights and food shortages.
Reproduction and Life Cycle
Here are some key points about ruby-throated hummingbird reproduction and life stages:
- Polygynous mating system – Males mate with multiple females. No pair bonds.
- Breeding season May-July
- Elaborate courtship displays by male – Aerial loops, dives, zipping flights to impress females.
- Tiny cup-shaped nests – Built solely by female with spider silk, lichen, down. Well-camouflaged high in a tree, 3-20 feet up.
- Two white eggs per clutch – About the size of a pea. Female incubates eggs 14-16 days.
- Chicks hatch blind, featherless – Weigh around 0.6 grams, fed regurgitated nectar and insects.
- Nestlings fledge at 18-22 days – Gain weight rapidly, up to 8 grams before leaving nest.
- lifespan 4-5 years
- Population stable – Estimated 7 million in North America. Safe from endangerment.
Females raise chicks alone without male assistance. Mother hummingbirds are highly aggressive in defending nests, even diving at much larger birds, animals, and humans that pass by. Ruby-throated hummingbird nests and eggs are vulnerable to predation from squirrels, cats, blue jays, snakes, etc. But their reproduction strategy balances those losses.
Behavior and Characteristics
Some interesting facts about ruby-throated hummingbird behavior:
- Highly territorial – Males defend flower-rich feeding territories from other males.
- Dawn singers – Males sing a short, squeaky song at dawn to attract mates and defend territory.
- Aggressive displays – Males perform dramatic dive displays, males and females may grasp each other in flight.
- Migrant rest spots – May gather in the hundreds overnight on migration at spots with abundant food.
- Bathe frequently – By flying through water droplets and preening.
- Sun themselves – Perch in open sun with wings widespread to control temperature.
- Anting – Coat themselves in ants to possibly gain nutrients or repel lice.
- Highly intelligent – Recognition skills, numerical skills, problem-solving, and exceptional memories.
- See UV light – Used to target nectar guides on flowers.
Despite their tiny bodies, ruby-throated hummingbirds are bold, feisty, and pugnacious in defending resources. They stake claim to floral territories and aggressively chase intruders in fast-paced skirmishes. Their characteristic throbbing wingbeat and blazing speed make them a flash of flying brilliance in gardens or forests.
Threats and Decline
Although still common and widespread, some major threats facing ruby-throated hummingbirds include:
- Habitat loss – Due to development, logging, agriculture.
- Pesticides – Contaminate flowers, reduce insect prey.
- Climate change – May alter bloom cycles, migration timing, reduce wintering grounds.
- House cats – Kill millions of birds each year including hummingbirds.
- Window collisions – Hummingbirds fail to see glass.
- Nectar competition – Honeybees may outcompete hummingbirds at flowers.
However, these threats are currently outweighed by the ruby-throated hummingbird’s ability to adapt. With a vast range and stable population numbers, the species has a positive conservation outlook. Targeted conservation initiatives can further safeguard ruby-throated hummingbirds, such as:
- Protecting migration routes and wintering grounds.
- Planting native nectar-rich flowers in gardens and parks.
- Keeping cats indoors.
- Avoiding pesticide overuse.
- Installing anti-collision measures on windows.
With appropriate habitat and foraging resources, ruby-throated hummingbirds can thrive within proximity to human settlements.
Significance to Humans
Ruby-throated hummingbirds provide enjoyment, inspiration, and ecological services:
- Backyard pleasure – Their acrobatics and glittering beauty make them sought-after garden visitors.
- Pollinators – Provide wildflower, garden, and commercial crop pollination.
- Pest control – Eat many tiny insect pests that damage trees, gardens, agriculture.
- Seed dispersal – Carry pollen on bill and head which aids plant reproduction.
- Indicator species – Sensitive to environmental changes, so reflect ecosystem health.
- Cultural inspiration – Featured in myths, art, poetry, jewelry, names of sports teams and vehicles.
- Tourist draws – Famed hotspots for viewing include Bosque del Apache NWR, Audubon Corkscrew Swamp Sanctuary.
The ruby-throated hummingbird’s remarkable migratory journey has captivated people for centuries. Their magical hovering flight and fiery plumage make them one of the most widely loved and observed birds.
Fun Facts
- Heart rate can reach 1,260 beats per minute.
- Only bird species that can fly backwards.
- Males perform aerial “dive displays” at speeds of 60 mph.
- Primary pollinator of cardinal flower, an important hummingbird-adapted plant.
- Banding records show oldest known lived 9 years, 5 months.
- High-pitched wings whir at an A-major chord.
- Their wings angle in a figure 8 for lift on both upstroke and downstroke.
- Ruby-red gorget color comes from prism-like structures in the feathers.
- A nest built with spider silk can stretch up to four times its size as chicks grow.
Conclusion
In summary, the ruby-throated hummingbird is classified in the order Apodiformes, family Trochilidae. It is the sole hummingbird species breeding in eastern North America. Ruby-throats are known for their diminutive size, glittering red throat, and amazingly fast hovering flight. They migrate long distances to winter in Central America and Mexico. Ruby-throated hummingbirds drink primarily flower nectar and tree sap, making them important pollinators. While still widespread and numerous, they face threats from habitat loss, climate change, and more. But they continue to be one of the most captivating, iconic birds that capture the imaginations of people around the world. Their speedy wings and aerial dances never fail to dazzle.
