Hummingbirds have fascinating and complex courtship rituals. When it’s time to find a mate, male hummingbirds will try to catch the attention of females through elaborate aerial displays, color changes, and song. If the female is impressed, she will allow the male to mate with her. After mating, the female builds a tiny nest and raises the chicks on her own as the male moves on to court other females. Let’s take a closer look at the stages of hummingbird courtship and what behaviors are displayed during this intricate process.
When does hummingbird courtship occur?
Hummingbird courtship and mating occurs in the spring and summer months. The exact timing depends on the species and its geographic location. In North America, ruby-throated hummingbirds generally begin courtship in late spring. Anna’s hummingbirds on the west coast start earlier, courting as early as late winter. The onset of courtship is triggered by increasing daylight hours.
How do male hummingbirds attract females?
Male hummingbirds use striking visual displays and song to catch the attention of females. Here are some of their courtship tactics:
Aerial displays
Males will fly in loops, dive bombs, and rapid ascents to show off their flying skills and the iridescent color of their throats. The male Anna’s hummingbird performs a dramatic aerial display, climbing 60 feet into the air and then diving straight down past the female.
Throat feathers
Many male hummingbirds have brightly colored, iridescent throat feathers (called a gorget). During courtship displays, they will fluff out these feathers and turn them toward the female. The vibrant flashing of the feathers helps attract attention.
Song
Male hummingbirds will sing complex songs to court females. Each species has a signature song. For example, the rufous hummingbird produces a buzzy chirp song, while the Anna’s makes loud squeaks interspersed with humming. Female hummingbirds have simpler songs used mostly for defending territory.
Behavior
Males will chase females aggressively in fast, acrobatic flight. This shows off the male’s strength and agility. They may also do pendulum flights in front of the female where they fly back and forth in a wide arc.
How do females respond?
If the female is not ready to mate, she will ignore the male or give chase to drive him off. But if she is interested, she will perch and watch his displays. She may give a soft call in response to his song. The female may also puff out her throat feathers. Once she chooses a mate, she is receptive for only a day or two before she resumes aggressive behavior toward males.
Mating
How do hummingbirds mate?
If the female hummingbird accepts the male, mating will occur. Here is how hummingbirds mate:
The female perches, and the male approaches
The female will perch in an open, exposed area at mid-level height. The male flies towards her in bursts of speed called power dives.
The male mounts the female
As he comes near the perched female, the male will mount her back and hold on using his feet. Hummingbirds have proportionally large feet with sharp claws that enable them to cling onto the female’s back or branch during mating.
Cloacal contact and transfer of sperm
Both male and female hummingbirds have a cloaca, which is a chamber and outlet for digestive, urinary, and reproductive systems. To mate, the male and female will press their cloacas together in what’s known as a cloacal kiss. This allows the male to insert his two sperm packets into the female’s cloaca where they will fertilize her eggs.
It’s over in seconds
The actual mating event lasts only 3-5 seconds. The male will then leave to mate with other females, and the female is left to build a nest and raise her chicks alone.
How often do hummingbirds mate?
Male hummingbirds are promiscuous and will mate with as many females as possible in a season. They do not form lasting pair bonds or help raise young. Females may also mate with multiple males. On average, each mating results in 2 eggs, so a female may have 4-6 eggs in a clutch from 2-3 matings.
Nesting and Parenting
After mating, the female must build a nest, lay and incubate the eggs, and care for the chicks on her own. Here are some key steps:
Nest building
The female builds a tiny cup-shaped nest out of soft plant down, spider webs, lichen, and moss. She binds it together with spider silk and attaches it to a branch using more silk. The nest is only 2 inches wide and 1 inch deep – just big enough for eggs and chicks.
Egg laying
Approximately 2 weeks after mating, the female lays 2 pea-sized white eggs. She may lay another set of eggs if she mates again during the breeding season. The eggs are only 0.5 inches long.
Incubation
The female incubates the eggs for 14-23 days. She sits on them nearly continuously, leaving only briefly to eat. Her body heat keeps the eggs at the proper warm temperature until they hatch.
Hatching
After 2-3 weeks of incubation, the eggs hatch. The chicks are only 0.6 ounces at birth, essentially naked and blind.
Feeding and care
For the next 3-4 weeks, the female alone feeds and cares for the chicks. She feeds them regurgitated nectar and insects, providing hundreds of meals as they grow. By the end of this period, the young hummingbirds are ready to leave the nest.
Key Facts About Hummingbird Courtship and Mating
Here are some key facts about the courtship, mating, and parenting of hummingbirds:
When
- Courtship begins in late winter or early spring depending on species.
- Mating happens in the spring and summer months.
- Females raise chicks alone through the summer.
Courtship Displays
- Males perform aerial displays, sing songs, and show off bright plumage.
- Females watch displays and may give soft calls.
Mating
- Lasts just seconds with cloacal touching.
- Males provide only sperm, no parenting.
- Females often mate with multiple males.
Nesting and Parenting
- Female builds tiny nest with spider silk.
- Female incubates 2 eggs for 2-3 weeks.
- Chicks hatch naked and helpless.
- Female feeds chicks hundreds of times until fledging.
Interesting Courtship Behaviors
Hummingbirds engage in some interesting behaviors related to courtship and mating. Here are a few fascinating highlights:
Dive displays
Male Anna’s hummingbirds perform an impressive aerial display by climbing 60+ feet into the air and then diving straight downward at high speeds past the watching female. This advertises the male’s strong flight skills.
Throat flashing
Male hummingbirds have iridescent throat feathers that they flash at females during courtship. The feathers change color depending on viewing angle. Flashing the feathers helps get a female’s attention.
Song duels
Sometimes males will engage in singing duels, performing their songs back-to-back as if in competition. This challenges rivals and shows off for females.
Body shaking
Males may perform ritualized body-shaking motions during courtship displays to accentuate their bright colors for onlooking females.
Dancing flights
In a pendulum or dancing flight display, a male flies back and forth in a wide arc pattern in front of the female to showcase his flying skills.
Threats to Courtship
Hummingbird courtship faces a number of threats from human activities and climate change:
Habitat loss
Loss of forests and meadows to development destroys nesting sites and flowering vegetation that hummingbirds need to breed successfully.
Pesticides
Chemicals and pesticides reduce insect populations that hummingbirds rely on for food to support the energy needs of courtship and nesting.
Climate change
Flower blooming and hummingbird migration is being disrupted, causing mismatches between courtship timing and food availability.
Light pollution
Artificial lighting can disrupt courtship signaling that relies on vision and interfere with biological rhythms keyed to natural light cycles.
Predators
Domestic cats are a major predator of hummingbirds, threatening mating, nesting success, and chick survival.
Overgrazing
Overgrazing by deer, cattle, and other mammals reduces wildflowers needed by hummingbirds for courtship feeding.
Why is Hummingbird Courtship so Complex?
Hummingbird courtship displays are remarkably complex and energetic. Here are some of the evolutionary reasons behind their elaborate mating rituals:
Proof of fitness
The aerial acrobatics and sustained displays act as proof of a male’s strength, health, energy, and flying capability. Females preferentially mate with athletic, fit males.
Species recognition
The unique courtship songs and rituals of each species help females identify appropriate mates and avoid hybridization.
Stimulate females
The elaborate displays visually and auditorily stimulate the female so she becomes physiologically ready to mate.
Competition between males
More dramatic and sustained displays help a male outcompete other rival males vying for female attention.
Trait exaggeration
Traits like colorful feathers, diving ability, and persistent singing are exaggerated through sexual selection and mate choice over time.
Energetic investment
A male’s willingness to spend considerable time and energy on courtship shows his ability to later invest in protecting and providing for offspring.
Conclusion
Hummingbird courtship is a complex process full of rituals and behaviors aimed at attracting a mate. Males dazzle females with color changes, songs, aerial displays, and vigorous flying to demonstrate their fitness. Females select a male suitor and mate for just seconds before moving on to build a nest and raise chicks alone. Courtship requires intricate energy-intensive behaviors because it kickstarts the reproductive cycle. Threats like habitat loss and climate change disrupt courtship, underscoring the importance of protecting these fragile birds. While the displays appear beautiful to us, they serve essential functions in the challenges of attraction, reproduction, and survival for hummingbirds.