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Unveiling the Wonders of Allen’s Hummingbird: Colors Movements Migration and Behaviors

Allen’s Hummingbird: A Gem Among Birds

Hummingbirds are quite unique birds, with their bright colors and darting movements. One species that stands out is the Allen’s Hummingbird(Selasphorus sasin), which is commonly found in the western region of North America.

Its vibrant colors and beautiful appearance, coupled with its small size, make it an attractive bird to bird watchers and nature enthusiasts alike. This article covers the identification, plumages, and molts of Allen’s Hummingbird, and aims to educate readers on the beauty of this bird.


Allen’s Hummingbird is a small bird that averages about 3.5 inches from beak to tail, and weighs about 3 grams. The male has a distinctive shiny green head and back, a rose-colored gorget, and a reddish-brown lower belly.

The female is less colorful, with a green head and back, a white breast, and a greenish throat. Both sexes have white tips on their tails, which can be seen when they fly.



Identifying Allen’s Hummingbird in the field can sometimes be tricky. Several other species of hummingbirds, such as the Rufous Hummingbird and the Anna’s Hummingbird, share their range and habitat.

However, there are some key features to look for that can help to distinguish Allen’s Hummingbird. The male’s reddish-brown lower belly is a unique trait that is not found in any other hummingbird.

Additionally, the female’s green back and lack of rufous coloration can help to differentiate her from the Rufous Hummingbird. Lastly, the white tips on the tail feathers are a distinctive trait of Allen’s Hummingbird and not found in any other species in its range.

Similar species

As mentioned earlier, Allen’s Hummingbird shares its range and habitat with other species of hummingbirds. Some similar species include:

– Anna’s Hummingbird: Anna’s Hummingbird is slightly larger in size and has a metallic green head and back, a red crown, and a dark, straight bill.

– Rufous Hummingbird: Rufous Hummingbird is similar in size to Allen’s Hummingbird, but the male has a bright orange-red throat and upper feathers, and the female has a rufous or brownish coloration. – Calliope Hummingbird: Calliope Hummingbird is smaller than Allen’s Hummingbird and has a metallic green head and back, along with a pinkish throat in males and white in females.


Allen’s Hummingbird has two plumages: breeding and non-breeding. During the breeding season, the plumage of both the male and female is more vibrant, with the male’s gorget being a bright rose color.

In the non-breeding season, their colors become more muted and duller. The molting process is essential in the development of plumage in hummingbirds.


Allen’s Hummingbird molts twice a year before and after breeding. Their feathers, much like all birds, have a lifespan.

Molting is the replacement of old feathers with new ones, which helps maintain feathers’ quality. Birds molt to replace feathers that have become damaged, worn out, or faded.

Allen’s Hummingbird replaces all its feathers once a year, starting with the body and ending with the wing and tail feathers. During this time, birds are more vulnerable, as their feathers may be less aerodynamically efficient.

In conclusion, Allen’s Hummingbird is an attractive bird that stands out with its vivid colors, small size, and darting movements.

Identification of this bird may be tricky, but by looking for specific field markings, birds can be easily distinguished from similar birds.

Their plumages and molt cycles are essential in revealing the beauty of these birds. Understanding the behavior and migratory patterns can have a significant positive impact on nature’s conservation measures and provide an immersive and gratifying experience for birdwatchers.

Allen’s Hummingbird (Selasphorus sasin) is an example of a bird species that experienced significant changes in its distribution, systematics, and geographic variation across its range. Through a brief overview of the historical changes in the distribution of Allen’s Hummingbird, this article outlines the subspecies, related species, and geographic variation of this bird species.

Systematics History

Allen’s Hummingbird is a species in the family Trochilidae, which includes approximately 340 species of hummingbirds. The species was first described in 1861 by John Gould, a British ornithologist, and artist.

The binomial name Selasphorus sasin was later given to it by the renowned American zoologist Spencer Fullerton Baird.

Geographic Variation

Geographic variation is the distribution of different subspecies over a particular geographic location. Allen’s Hummingbird shows limited geographic variation across its range.

There are a few geographic variations noted among the populations of Allen’s Hummingbird. The birds closer to the coast have a darker and more metallic iridescent sheen, while those in the interior regions have a duller iridescence.

These geographic differences noted among this species’ populations are attributed to genetic differences, as well as differences in habitat.


Subspecies are geographically isolated populations of a species possessing distinct characteristics from the original species. Allen’s Hummingbird is a highly variable species and has at least three recognized subspecies:


Selasphorus sasin sasin: This subspecies has a breeding range spread across the west coast of the United States, from northern Baja California in Mexico to southern Oregon. 2.

Selasphorus sasin sedentarius: This subspecies is endemic to Santa Barbara Island off the coast of Los Angeles, California. 3.

Selasphorus sasin lagunae: This subspecies is found on the islands of the Gulf of California. In 2021, a new subspecies, Selasphorus sasin farallonensis, was identified from the Farallon Islands off the coast of California.

Related Species

The genus Selasphorus has several species of hummingbirds. Among them, the Rufous Hummingbird (Selasphorus rufus) is the most closely related to Allen’s Hummingbird.

The two species share overlapping geographic ranges and show a high degree of genetic similarity, which has led to taxonomic difficulties in the past. Nonetheless, they are distinct species, as Allen’s Hummingbird lacks the bright rufous coloring and white chest found in Rufous Hummingbirds.

Historical Changes to Distribution

Allen’s Hummingbird has experienced some significant historical changes to its distribution. It is a sedentary species and only moves short distances in search of appropriate feeding and breeding habitat.

However, the species has expanded its range over the past century. It originally occupied a narrow range along the west coast of North America, but it has since expanded its range further inland.

Since the early 20th century, the breeding range of this species has been documented to have extended northwards. This is believed to be due to the bird’s adaptation to suitable habitats, such as gardens, parks, and nectar feeders, especially during winter.

Additionally, climate change may have contributed to the species’ historical range expansion. Interestingly, the distribution of Allen’s Hummingbird also appears to have shifted northwards as a result of human activities.

The species’ range in British Columbia, Canada, has been documented to have expanded significantly in recent decades. This expansion is believed to have been facilitated by the cultivation of ornamental flowers, which is becoming more popular in the region.


In conclusion, Allen’s Hummingbird is a species with an interesting history of distribution, systematics, and geographic variation. The species’ limited geographic variation and distinct subspecies, as well as its close relation to the Rufous Hummingbird, make it an exciting bird species to study.

Historical changes to its range have shown adaptation to habitat availability, human activities, and potential impacts of climate change. These changes highlight the importance of understanding the biology, ecology, and geographical spread of bird species for effective conservation measures.

Allen’s Hummingbird (Selasphorus sasin) is a small bird species found in North America with a broad range of habitats. They are known for their vibrant colors, and many people enjoy watching them dart around in their natural habitat.

This article will provide a detailed overview of Allen’s Hummingbird’s habitat, movements, and migration.


Allen’s Hummingbird is found in a range of environments across North America. They occupy coastal sagebrush, oak savannas, chaparral, and other semi-arid habitats.

The species requires year-round access to a reliable nectar source, and birds can thrive in urban environments if there is adequate flowering vegetation available. However, the size of their habitat depends on the altitude, latitude and can vary dramatically.

Typically, riparian woodlands provide a prime habitat for Allen’s Hummingbird due to the abundance of flowering shrubs and trees in those habitats. Allen’s Hummingbird is a territorial species as it strongly defends its foraging resources or nesting sites.

It easily adapts to human-altered habitats, natural or ornamental gardens, and suburban landscapes all year-round.


Allen’s Hummingbirds live in defined territories year-round. They won’t move around much and will instead defend against intruders and other hummingbirds and may chase them away.

During non-breeding periods they may travel some distance in search of food, but typically they’ll stick to their limited range.


While many hummingbird species are known for their long-distance migration, Allen’s Hummingbird has a relatively small migration range. The majority of Allen’s Hummingbird’s range does not experience significant variations in climate across months, thus they are non-migratory in most parts of their breeding range, except for a small population in San Clemente Island.

The island’s population has more seasonal migrations due to the island’s limited resources. Still, they can travel as far as 700 miles across the Gulf of Mexico and the Caribbean, making brief stops to feed to reach the breeding grounds in the southern United States and Mexico by March.

Interestingly, in recent years, there has been evidence suggesting that some individuals that breed in the Pacific Northwest have expanded their summer ranges. These birds might be migrating eastward to the Rocky Mountains.

Researchers are still assessing the extent, frequency, and implications of these movements. Climate change is predicted to affect bird species’ migration patterns and movements, and the impact on Allen’s Hummingbird is unknown.


Allen’s Hummingbird is a fascinating species with a complex relationship with its environment. It occupies a wide range of habitats, though riparian woodlands are prime places with abundant flowering shrubs and trees which provide a reliable source of nectar.

The species is mostly non-migratory, and they defend their territories year-round. However, some individuals in the Pacific Northwest region have started expanding their range during summer.

Understanding the movements and migration patterns of this species is crucial for effective conservation measures and maintaining critical habitats for these beautiful birds known for their vibrant hues and remarkable agility. Allen’s Hummingbird (Selasphorus sasin) is a bird species known for its vibrant colors and rapid movements that can quickly dart around in search of nectar.

This article provides detailed information about their diet and foraging behavior, as well as sounds and vocal behavior.

Diet and Foraging


Allen’s Hummingbirds are exclusively nectarivores that feed on nectar, which they obtain by sipping nectar from flowering plants, such as California buckeye, monkey flower, and chemise. They are known to hover in front of the flowers while sipping nectar through their long and thin beaks, and their tongues are specially adapted to extract liquid nectar.

Allen’s Hummingbirds’ large proportion of their daily metabolic rates are from foraging, making it crucial to their fitness.


Allen’s Hummingbirds feed on a diet high in sugar and energy, with some insects as a source of protein for growth and development. If they fail to obtain sufficient carbohydrates, protein, or have limited resources from nectar, their ability to withstand low temperatures may decline.

The variation in their availability of nectar tax the hummingbird’s foraging behaviour, leading to their high energy needs that accommodate this high activity level. The nutritional quality of nectar depends on its concentration, which varies with the seasonal availability of flowering plants.

Metabolism and Temperature Regulation

The high foraging activity of Allen’s Hummingbird also translates to their metabolic rate. Their metabolism is unusually high for their small size, much faster than other birds of comparable body size and mass.

Their metabolism helps them maintain their body temperature. They need to maintain high metabolic rates to balance their smaller size and low body fat.

When their body cools below a particular temperature, they shiver to generate body heat. They have the ability to go into torpor to navigate periods when flower nectar levels are low, temporarily reducing their metabolism by as much as 99% to save energy.

Sounds and Vocal Behavior


Allen’s Hummingbirds are known for their distinctive vocalizations, and their vocal behavior has an essential role in communication, especially during breeding season. hummingbirds don’t produce conventional songs associated with other birds’ species.

Still, instead produce a variety of chirps, chirrs, and other vocalizations. Hummingbirds have unique muscles in their vocal tract that let them produce sound in two ways, one during inhaling, producing a non-tonal chirp, and one during exhaling that produces the more familiar tone.

The species song varies with the region and subspecies, ranging from short, high-pitched trills to longer, swooping, slightly ground notes or sharp metallic buzzes. In addition to sounds that are audible to humans, Allen’s Hummingbird produces sounds that are beyond the range of human hearing.

During their courtship rituals, males produce high-pitched, ultrasonic sounds that only other birds can hear. These sounds are thought to have a role in mate attraction, as they can provide an acoustic signal that suggests the male is a good mate, providing interested females with the information they need to select a high-quality partner in the absence of visual clues.


Allen’s Hummingbird is a fascinating species known for its energetic foraging behavior and vocalizations. Their food choices and high metabolic rate reflect their need for energy, and their vocalizations play a critical role in communication, particularly during breeding season.

Understanding these important aspects of the species’ natural history is crucial to conservation measures to protect habitats and support the health of these remarkable birds. Allen’s Hummingbird (Selasphorus sasin) is an energetically highly active bird species that is well known for its vibrant colors, rapid movements, and unusual breeding behavior.

This article provides detailed information about their behavior, breeding, demography, and populations.



Allen’s Hummingbirds display a swift and coordinated flight, which enables them to hover in place, fly backward, and change direction quickly. The species has evolved several adaptations for their unique locomotion, including significant pectoral muscles and a more massive sternum.

Their wings are more flexible and progress in a figure-eight shape, creating a lift and torque that allows them to fly forward, backward, or hover stationary while feeding.

Self Maintenance

Allen’s Hummingbirds engage in self-maintenance behaviors, such as preening their feathers and producing oil to keep their feathers healthy, clean and waterproof. They can also be witnessed sunbathing, which helps keep their feathers dry, aiding better flight.

Agonistic Behavior

Despite their diminutive size, Allen’s Hummingbird is known for their aggressive and territorial behavior, and they fiercely defend their territories and foraging resources. Individuals will use acrobatic aerial displays to chase off intruders and other hummingbirds and are known to engage in elaborate vocal and visual displays to deter rivals and attract mates.

Sexual Behavior

During the breeding season, males perform display flights to attract a mate, including elaborate dive flights from perch to perch, producing a distinctive whirring sound with their feathers during these dives. The male dancing display flight patterns depend on their size, age, and individual variation.


Allen’s Hummingbird reproduces sexually, with females typically producing two small eggs during breeding season. They build cup-like nests out of spiderwebs, lichen, and plant fibers, and they lay their eggs inside.

The males play a significant role in mating, defending territories and performing courtship displays to attract potential mates. Female bird choice is present in Allen’s Hummingbird, with females choosing their mates based on the bright colors and displays they produce.

Demography and Populations

Allen’s Hummingbird populations have been declining in recent decades due to habitat loss and climate change. Conservation measures are being taken to help conserve populations, such as monitoring and tracking bird movements, creating protected areas and restoring habitats, and educating the public about the species.

Research into population demographics, such as breeding patterns, mating behaviors, and foraging, is essential to understanding population trends and developing conservation strategies. Allen’s Hummingbirds have variable population sizes depending on location, season, and environmental conditions.

For instance, the species is more abundant along the coast throughout its range than it is inland, where it is seen mostly during migration. Furthermore, recent population analysis suggests that populations in the northern region are increasing, while populations in the southern regions are declining.

The reasons for this demographic change revolve around climate change, habitat disruption and changes in plant flowering pattern, which can significantly influence nectar

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