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The Elegant Velvet-Browed Brilliant: Discover the Unique Features and Behaviors of this Breathtaking Hummingbird

Velvet-browed Brilliant: An Elegant Trochilidae

Hummingbirds are undoubtedly one of the most striking bird species out there. Their iridescent plumage, rapid flight, and hovering technique never leave bird lovers indifferent.

Within the vast family of Trochilidae, the Velvet-browed Brilliant (Heliodoxa xanthogonys) stands out for its unique features. Keep reading to learn more about one of the most elegant and breathtaking hummingbirds of the American continent.

Identification

Field Identification

The Velvet-browed Brilliant is a medium-sized hummingbird, measuring about 11 cm from beak to tail. It has a straight, thin bill, dark green above, but black-tipped.

Its upperparts are mostly green, and it has a turquoise gorget that can appear black depending on the angle of light. The rest of the underparts are vanilla-white.

The most remarkable feature is the vibrant, velvet-like black crown that reaches the nape, contrasting with the pale green sides of the head. Finally, its wings are a subtle grey-green, with a pale band in the center and dusky tips.

Similar Species

Although it is relatively easy to discern H. xanthogonys from other hummingbirds thanks to its distinctive features, there is a possibility of confusion with two related species: H.

spencei and H. aurescens.

Both rivals have turquoise throats too, but lack the black crown of the Velvet-browed Brilliant. Moreover, H.

spencei has a golden-green forehead and green sides of the head, while H. aurescens has a chestnut belly and a curved bill.

Plumages

The Velvet-browed Brilliant only has one defined plumage. However, it is subject to daily wear and tear due to its agile and energetic nature, causing the feathers to lose their shine and colour intensity quite easily.

Therefore, if you have the opportunity to watch closely a perched example, you may notice some variation in plumage intensity according to wear and age. Older examples might show faded or brownish feathers instead of crisp green ones.

Molts

As it happens with other hummingbirds, the Velvet-browed Brilliant undergoes two molts per year: one partial and one complete. The first, or prebasic molt, starts in the summer and lasts until early autumn.

During this time, the bird will replace its body feathers. Some individuals will molt their head feathers too.

The second molt, or prealternate molt, starts in late winter or early spring. This one is complete, meaning that the entire plumage will be replaced.

The new feathers will shine brightly and show an intense green hue that fades as the feathers age. In conclusion, the Velvet-browed Brilliant is an extraordinary hummingbird species among the trochilidae family.

Its distinct features like the black velvet crown and vanilla-white underparts, with a turquoise gorget and green upperparts and wings, make it a unique bird to witness. Next time youre in the Andean region of South America, keep an eye out for this incredible bird species.

Systematics History

The Velvet-browed Brilliant (Heliodoxa xanthogonys) is a beautiful and charming hummingbird species that belongs to the Trochilidae family, commonly known as the hummingbirds. It was first identified by Adolphe Boucard in 1893 and has undergone several changes on the systematic hierarchy since then.

Geographic Variation

The Velvet-browed Brilliant is widely distributed across the Andean region of South America, including Ecuador, Colombia, Peru, and Bolivia. Though the species maintains relative homogeneity, certain instances of geographic variation have been observed in its plumage, body size, and shape across its range.

Subspecies

Within the Velvet-browed Brilliant species, there are two generally recognized subspecies H. x.

corneliae and H. x.

xanthogonys. H.

x. corneliae.

This subspecies occupies the northernmost and southernmost part of the species range, distributed from Colombia to Ecuador and from northern Peru to south-central Peru. It is also sometimes referred to as the Peruvian Velvet-browed Brilliant, and it has more vibrant and brighter plumage coloration compared to the southern subspecies, H.

x. xanthogonys.

H. x.

xanthogonys. This subspecies encompasses the central range of the Velvet-browed Brilliant species, found in the Andean region of central Peru and western Bolivia.

This subspecies often shows a more muted coloration, with more green and less blue hues than H. x.

corneliae.

Related Species

The Velvet-browed Brilliant is one of the many beautiful species of hummingbirds. In a broad sense, it has been placed in the genus Heliodoxa, which has seven other recognized species that exist primarily in the northern part of the Andes.

H. gularis.

This species, also known as the Black-throated Brilliant, inhabits open areas, gardens, and forest edges of Venezuela, Colombia, and northwestern Ecuador. Males of this species have dark throats, a glittering green crown and back, and turquoise iridescence underparts.

H. leadbeateri.

This species, also known as the Violet-fronted Brilliant, inhabits montane forests and forest edges of Costa Rica, Panama, Colombia, and northwestern Ecuador. The male has a bright emerald-green underpart with a violet-blue forehead.

Historical Changes to Distribution

The Velvet-browed Brilliant’s distribution has undergone significant historical changes in both directions of geographic variance. During the Pleistocene epoch (approximately 2.6 million to 11,700 years ago), the Andean region underwent substantial changes in climate, specifically caused by several times of glaciation and warming that fragmented and reshaped the vegetation of the region.

These environmental shifts led to the establishment of refugia in the Andean region, which enabled the survival of many plant and animal species. Recent estimates showed that the Velvet-browed Brilliant and its related species Heliodoxa schreibersii had ancestors occupy a widespread distribution across the Andean region during the last glacial period (~18,000 years ago).

Then, changes in vegetation and climate caused these ancestral populations to become isolated, leading to speciation and, eventually to the establishment of distinct geographical subspecies. In the early twentieth century, rapid deforestation and land clearing for agriculture, urbanization, and other human activities led to the significant declination of the Velvet-browed Brilliant population in certain areas of its range, especially in Bolivia and Colombia.

However, in recent years, efforts have been made to attempt to re-establish the Velvet-browed Brilliant population in urban green spaces, botanical parks, biological reserves, and other protected areas in different parts of its distribution range. These conservation efforts have resulted in significant progress in population conservation and expansion in the Ecuadorian Choc region, where the Velvet-browed Brilliant has benefited significantly from these conservation efforts.

In conclusion, the Velvet-browed Brilliant is an interesting and uniquely distributed hummingbird species in the Andean region of South America, which exhibits geographic variation and diverse distribution ranges due to historical factors. Despite its unique beauty, threats such as habitat loss, hunting, and climate change have led to a steady decline in its population throughout its distribution range.

Although current conservation efforts may seem to be advancing in some areas of its range, a comprehensive and integrated approach is required to ensure the long-term survival of this striking bird species.

Habitat

The Velvet-browed Brilliant is primarily an Andean forest species, occupying different altitudinal zones ranging from dry scrub forests to misty and humid mountain forests. This species can inhabit subtropical and humid montane primary forests, secondary forests, and forest edges.

The distribution area of the Velvet-browed Brilliant ranges from 800 to 2800 meters above sea level. However, this species may occasionally be present above that elevation in particular areas of its range.

Movements and Migration

The Velvet-browed Brilliant is a resident bird species, which means that it does not undergo regular long-distance movements or migration. However, it has been observed that some individuals undertake seasonal altitudinal movements.

During the wet and dry seasons, the Velvet-browed Brilliant may move to more favorable areas to look for nectar and breeding opportunities, depending on resource availability in its habitat. Typically, during the dry season, when the flowers and vegetation are less abundant and drier, the hummingbirds may move to wetter and more productive forests, while during the wet season, they may move towards drier areas.

The research conducted by Snow et al. (1998) suggested that some Velvet-browed Brilliant populations undertake movements between different altitudinal zones.

For example, they clearly observed birds that moved from higher to lower altitudes during the dry season in Bolivia. However, Snow et al.

(1998) also noted that these altitudinal movements may not have been strictly the result of seasonal resource shifts, as lowlands and forest edges above 800 meters could be seasonally dry and unproductive as well.

Breeding and Reproduction

The breeding season of Velvet-browed Brilliant coincides with the wet season, which varies depending on the exact location and changes in climate. The onset of the breeding season is influenced by a combination of factors such as temperature, precipitation, and light variation throughout the day.

Male Velvet-browed Brilliant is known to perform an elaborate courtship display to attract females. During courtship, the male performs a “pendulum display” in which he swings back and forth, hovering in front of the female while vocalizing sharply.

These short, high-pitched sounds resemble those produced by a cricket. The female Velvet-browed Brilliant constructs a small, cup-shaped nest using soft plant material, moss, and spider webs, which are typically situated on the outer end of a branch.

The nest is suspended over potential predators, locating about 1 to 3 meters above the ground in low vegetation, including ferns or epiphytes. After copulation, the female lays two elongated, white eggs that are approximately 13 mm in length.

The eggs hatch after about 16 to 18 days, and the hatchlings are nourished by the mother’s crop milk, which they actively consume. The chicks fledge after about 21 to 23 days of age and become independent after a few weeks.

Conservation and Threats

The Velvet-browed Brilliant is relatively common across its range and is not considered at risk of extinction currently. However, habitat loss and degradation due to human activities, such as agriculture, mining, and urbanization, may pose a significant threat to the species’ future viability in certain areas.

Furthermore, the climate change-related variations in temperature and precipitation may also affect the habitat distribution and availability of the Velvet-browed Brilliant. The fragmentation of the habitat due to human activity may lead to isolated sub-populations, leading to genetic diversity loss and increased risks of local extinctions.

Nevertheless, the conservation of the Velvet-browed Brilliant and its habitat can provide significant benefits to many other endemic and threatened bird species that exist in the Andean region. The establishment of more protected areas, the legal protection of habitats, and supporting forest restoration practices can contribute to preserving the future viability of this unique and vibrant species.

In conclusion, the Velvet-browed Brilliant typically inhabits Andean forests, where it forages, handles its courtship, and nests in humid subtropical and montane forests. Altitudinal movements of this species may occasionally occur as part of the search for more favorable habitats and resources, but it is primarily a resident species.

The breeding season is closely related to the wet season, and the female constructs a small, cup-shaped nest in low vegetation. Although not currently at risk of extinction, habitat loss and climate change pose significant threats to the future viability of the Velvet-browed Brilliant, and therefore, habitat conservation and restoration efforts must be continued.

Diet and Foraging

The Velvet-browed Brilliant is a nectarivorous bird species that feeds primarily on nectar from flowers. The species has a long, thin bill, which is well-adapted for probing deep into flowers to access nectar.

Feeding

The Velvet-browed Brilliant is an agile and energetic bird species, making use of its sharp vision and hovering flight to locate and access nectar-containing flowers. Once it locates a suitable flower, the bird inserts its long bill and sucks the nectar using its highly specialized tongue that can protrude well beyond the bill tip.

During feeding, the bird may cling or perch on the flower stem, flicking its wings rapidly to maintain its position.

Diet

Although nectar is the primary food source for the Velvet-browed Brilliant, this species can also supplement its diet with insects and spiders, primarily to obtain essential amino acids, fat, and minerals that are not present in nectar in sufficient quantities. Studies conducted by Snow and Lill (1974) confirmed that different hummingbird species, including the Velvet-browed Brilliant, can derive up to 50% of their total energy from eating insects.

Metabolism and Temperature Regulation

The Velvet-browed Brilliant and other hummingbirds have an extremely high metabolism compared to other bird species. This metabolic rate is essential to support the high rate of energy expenditure needed for their intense flight and hovering.

To support such a high metabolic rate, hummingbirds such as the Velvet-browed Brilliant have several physiological adaptations. These include a significantly higher heart rate that can exceed 1000 beats per minute, highly efficient respiratory systems, and a unique gastrointestinal system that allows them to digest food very rapidly.

Additionally, the Velvet-browed Brilliant has a flexible metabolism, relying only a little on fats or carbohydrates during high-altitude flight but focusing energy expenditures on burning oxygen directly. Hummingbirds must also maintain their body temperatures at a very high level to support such a high metabolism.

The Velvet-browed Brilliant and other hummingbird species have the highest body temperatures of any bird species, usually between 40 and 42 degrees Celsius, which they maintain through precise temperature regulation.

Sounds and Vocal

Behavior

Vocalization

The Velvet-browed Brilliant has distinctive vocalizations, primarily used for territorial displays and courtship. The species produces a series of high-pitched and distinct sounds, including a “twittering” trill and a loud, explosive “kat” call.

During courtship displays, the male Velvet-browed Brilliant performs the pendulum display, as discussed earlier, while simultaneously making sharp, high-pitched chirping sounds. Additionally, both males and females will produce twittering calls, referred to as “peeps,” during feeding and other social interactions.

Interestingly, the Velvet-browed Brilliant and other hummingbird species have specialized vocalizations that they use to communicate with one another without expending energy. These vocalizations, referred to as “non-song sounds,” include clicks produced by the hummingbird bill movement and “wing-swoosh” sounds created by the motion of rapidly flicked wings.

In summary, the Velvet-browed Brilliant is a nectarivorous bird species that supplements its diet with insects and spiders. The species has an extremely high metabolism rate, requiring several physiological adaptations to support intense flight and hovering.

The Velvet-browed Brilliant has a unique vocalization, including “kat” calls, “peeps,” and “non-song sounds,” used for social interactions and communication.

Behavior

The Velvet-browed Brilliant is an energetic bird species that exhibits a variety of behaviors related to locomotion, self-maintenance, and social interactions.

Locomotion

The Velvet-browed Brilliant is an agile bird species that moves quickly through forested areas using its powerful wings to fly and hover. Its wings are adaptable, allowing it to maneuver quickly in tight spaces, such as narrow flowers where it obtains nectar.

During courtship, the male species perform the pendulum display using their wings.

Self-Maintenance

Hummingbirds, including the Velvet-browed Brilliant, are known for their fast metabolism and high-energy behavior. To maintain their physical abilities and high metabolic rates, hummingbirds engage in self-maintenance behaviors such as preening, sunning, and bathing.

The Velvet-browed Brilliant often suns itself, topping up its energy reserves. Agonistic

Behavior

The Velvet-browed Brilliant is territorial and defends its food resources and breeding sites from other bird species.

They display a range of agonistic behavior, including aerial chasing, flying into a competitor’s territory to defend their territory, and lunging at opponents. Sexual

Behavior

The Velvet-browed Brilliant engages in sexual behavior during the breeding season by releasing melatonin, which stimulates testicular growth and hormone production.

Male birds perform courtship displays, such as pendulum displays, which indicate fitness to potential mates. The female bird usually constructs a small cup-shaped nest in low vegetation and is responsible for incubation and brooding of the eggs while the male defends their nesting site from other bird species.

Breeding

The breeding season of the Velvet-browed Brilliant usually coincides with the wet season, which varies from place to place. The female makes a small, cup-shaped nest using soft plant material, moss, and spider silk, typically located on the outer end of a branch, suspended above potential predators like tree snakes.

The female lays two elongated, white eggs, which hatch after 16 to 18 days of incubation. After hatching, the chicks are nourished by the mother’s secreted crop milk, which they actively consume until they fledge at around 21 to 23 days of age

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