Ruby-throated Hummingbirds are one of the smallest birds. However, they are enduring fliers. They can cover large distances during seasonal migration with their swiftly flapping wings during the Ruby-throated Hummingbird migration.
But, did you know that they are the only birds with this unique characteristic of flying backward? Yes, it’s true!
Amongst all the other species of birds, Ruby-throated Hummingbirds are the most studied and sought-after birds. They can see spectrums of light that humans are blind to, one such example is ultraviolet light.
This Hummingbird species is able to see things that are extremely far, but they have better vision than humans. They also hear better, although they cannot smell. They rely on their eyesight when they are in search of their prey. Bright colors such as red and yellow attract them.
As they feed on nectar, the bright colors of the flowers indicate higher content of nectar. Read on to know more about these charming creatures and the Ruby-throated Hummingbird migration.
Identifying Ruby-throated Hummingbirds
The adult Ruby-throated Hummingbird has a plumage of metallic green on its upper body and grayish-white on the lower body. Its wings are of a light black hue.
It has a long, thin, and straight beak; this helps them suck nectar from the flowers. The beak is about 2 cm long. The adult Ruby-throated Hummingbird is about 7 to 9 cm long and has a wingspan between 8 to 11 cm.
The average adult Hummingbird weighs between 2 to 6 g. The average male in this species weighs around 3.4 g. The females in this species of Hummingbird are slightly larger and weigh about 3.8 g.
The feet and toes of all Ruby-throated Hummingbirds are tiny, although they can scratch their necks and heads with their legs and also move along a branch.
This species is named ruby-throated because of the ruby red gorget of the male Ruby-throated Hummingbird. This patch is iridescent and has a black outline above.
The tail is diverging and is black. This ruby throat appears black from some angles. The females have notched feathers. These have strips of green, black, and white. They also have a plain white-colored throat and, in the other, stippled or streaked in some females.
The male Ruby-throated Hummingbird has shorter beaks than the female. Because of the marked throat, the child phase of these birds resembles the female.
From the beginning of fall to the end of winter, the Ruby-throated Hummingbird’s plumage molts on their wintering grounds during their migration period.
Ruby-throated Hummingbirds use their vocalizations primarily to indicate any threats. They have rapid, chirpy, and squeaky vocalizations. A male uses them to warn other males when they enter the territory. However, during courtship, they make the sound with their wings. The males make this sound and it is very rapid.
Where to Find Ruby-throated Hummingbirds
You can find Ruby-throated Hummingbirds in North America, specifically east of the Mississippi River. They spend their winters in their breeding grounds located in Central America, northern Mexico, and Florida.
Ruby-throated Hummingbirds migrate to gardens, open woodlands, meadows, and any other places that have bright-colored flowers. These Hummingbirds are well acquainted with humans; therefore, you can usually find them in the suburbs or small towns. They are also found in birdwatching backyards, porches, and windows.
Ruby-throated Hummingbirds usually rely on the nectar from the flowers for their nutrition. Besides nectar, they feed on spiders and small insects. Adult Ruby-throated Hummingbirds also feed on tiny arthropods for protein, minerals, and vitamins. They will occasionally feed on sap because it is rich in sugar from the sapsucker wells.
They feed on the flowers by hovering, they extend their bills and long tongues in the center of the flowers and suck the nectar. These Hummingbirds fly out and use their long tongues to catch insects from the foliage. They sometimes remove the spiders out of their cobwebs to feed on them. They especially need to have a surfeit of energy from nectar and other resources during the long Ruby-throated Hummingbird migration.
The younger Ruby-throated Hummingbirds feed on insects as they provide sufficient protein and nutrients that they wouldn’t be able to find in nectar. The younger Ruby-throated Hummingbirds require a protein-rich diet because they need it for their growth and development.
Ruby-throated Hummingbirds are solitary birds. They do not migrate in flocks, neither are they social. The only time these birds interact is during courtship and when the female raises the young ones. Ruby-throated Hummingbirds be it a young one or an adult, all are aggressive with each other. They tend to defend their territories; they attack or chase the other Ruby-throated Hummingbirds out of their territory.
During the spring migration, Ruby-throated Hummingbirds double their fat mass to conserve energy for the 20-hours-non-stop flight across the Gulf of Mexico. This energy conservation is due to the fact that food or water will be unavailable during this long and arduous journey. This migration path covers a distance of 800 km. The average weight of a Ruby-throated Hummingbird is 3 g, and it is difficult to store so much energy to travel so far; hence they tend to
double their fat mass.
Hummingbirds have one of the highest metabolism rates, with a heart rate of 1260 beats per minute. A really intriguing fact about Ruby-throated Hummingbirds is that their oxygen consumption per gram of muscle tissue during their migration is about ten folds higher than that of an elite human athlete. To conserve energy, they feed actively during the entire day and so that they can ensure a surplus of energy in the winter season.
Breeding and Nesting
Ruby-throated Hummingbirds are polygynous, this means that they have a mating system in which one male mates with several females throughout his lifetime; however, females mate with only one male. Polygynandry, where several females mate with several males during the breeding system, and polyandry, where one female mates with several males, also occur in Ruby-throated Hummingbirds. There is no specific breeding pattern.
The parental care is provided by the females only. The males leave right after the mating season for Ruby-throated Hummingbird migration. Before the breeding season, the males reach the breeding grounds and mark their territory. After the females arrive, the males perform a courtship display in order to court the females.
They build their nests on downward sloping tree branches. Hornbeam, hackberry, poplar, oak, and birch are some of the preferred deciduous nesting locations. Sometimes, you can find their nests on chains, wires, or even extension cords. The construction of a Ruby-throated Hummingbird nest is complex because there are various materials that they use to secure them.
The exterior consists of bud scales and lichens, the spider’s silk binds it. Lastly, they line their nests with fibers. Usually, the fibers consist of down or animal hair. These nests are also camouflaged well to keep them safe from predators. The nests are so sturdy that they last for many seasons. However, an annual repair is done to maintain it. Like all the other species of Hummingbirds, even in Ruby-throated Hummingbirds, the females alone construct the nest, incubate the eggs, and raise their off-springs.
Females usually lay about one to two eggs; they are white in color. They have one to two broods each summer. The females incubate their eggs for twelve to fourteen days. The female Ruby-throated Hummingbirds feed the offspring once to thrice every hour by the method of regurgitation. The young ones make their first flight after they are 18 to 22 days old.
Why do Ruby-throated Hummingbirds migrate?
It is shown on the bird migration map that one of the first species of Hummingbirds surfaced in South America around 22 million years ago. They arrived in South America from Asia. Later, from South America, the species spread farther. Some landed in Central America, the Caribbean, and mainland North America. As the food resources increased, the species of Hummingbirds observed less competition for territories and food, and eventually, the species evolved.
The weather conditions lead them to migrate southwards during winters. The bird migration pattern of these species is such that it seems like a cycle of advancing and retreating as the seasons change.
Migration Routes and Patterns
Ruby-throated Hummingbirds have one of the longest bird migrations. Due to the long migration routes, they need to have flight agility. Therefore the skeletal and muscle adaptations have to lead them to develop flight agility.
The body of Ruby-throated Hummingbirds comprises 25 to 30% of muscle weight. Their wings are like blades that are connected only at the shoulder joint, this is an anatomical feature that is not seen in any other birds. This type of development in their wings allows the wings to rotate 180 degrees. The rotation is advantageous as it aids the birds to fly forward and backward and even hover in mid-air while feeding. This flying pattern and ability are similar to that of the birds. However, it is not common in birds.
The first arrival of Ruby-throated Hummingbirds is during Spring, in Texas and Louisiana. This happens anytime between late February to mid-March. These arrivals keep changing depending on the weather and environmental conditions.
During the northwards trip, Ruby-throated Hummingbirds have a migration path over the open waters of the Gulf of Mexico. It is said that the Ruby-throated Hummingbirds’ migration route is one of the most difficult ones because they are constantly flying around 18 to 22 hours to reach their seasonal migration homes. Their energy and tenacity are admirable, considering that they have a relatively higher metabolism rate, affecting their energy reserves.
Ruby-throated Hummingbirds spend their winters anywhere from southern Mexico to northern Panama. The reason why the wintering ground’s range is so extensive is that the Ruby-throated Hummingbirds prefer to travel individually, so the chances of exploring many locations increases. The migration pattern of Ruby-throated Hummingbirds is very diverse and can be observed from their bird migration map.
Research shows that Hummingbirds migrate in response to environmental triggers. A change of light or angle of the sun is one of the triggers. When food resources become scarce, it is another trigger of the Ruby-throated Hummingbird migration.
Ruby-throated Hummingbirds begin to molt as soon as they complete their fall migration.
Ruby-throated Hummingbirds surfeit food such as nectar and insects, preparing to migrate again towards the North.
This time of the year is relatively slow, and the feathers start developing. In order to keep flying, the Ruby-throated Hummingbirds need a lot of nectar. They are always found near food sources.
The breeding season arrives, and Ruby-throated Hummingbirds conserve all the energy resources to prepare for flying North. They start their journey from Mexico and Central America begins in late February towards the North.
Ruby-throated Hummingbirds have been studied comprehensively over the years. Hummingbirds and their species are unique and possess different features and patterns from the other species of the birds.
The Ruby-throated Hummingbirds create humming sounds by beating their wings rapidly. They are named after these unique characteristics. Most birds can be seen with their flocks on their migration routes. However, the Ruby-throated Hummingbirds travel individually.
Despite being amongst the smallest birds, did you know that the Ruby-throated Hummingbird migration is the longest bird migration? Since Ruby-throated Hummingbirds are not endangered, birders are allowed to attract them to their birdwatching backyards.
However, many precautions must be taken to conserve this species. If birders are luring them into their backyards, they must ensure that the backyards do not possess any threats of cats or other predators of Ruby-throated Hummingbirds. The bird feeders should be away from the windows, as the birds may see their reflections and might attack the windows assuming that it is an invader in the territory. You can set goals to bird-watch for these Cranes and record your results.