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Discover the Secrets of the Bearded Mountaineer: A Rare Andean Jewel

The Bearded Mountaineer, also known by its scientific name Oreonympha nobilis, is a bird species native to the Andean mountain range in South America. This small but striking bird is known for its colorful plumage and unique physical features.

In this article, we will delve into the various aspects of the Bearded Mountaineer, from its identification and field marks to its plumages and molts.

Identification

The Bearded Mountaineer is a small bird, measuring approximately 10.5 cm (4.1 in) in length. It has a short, straight bill and distinctive black and white stripes on its face, giving it a bearded appearance.

The upperparts of the bird are a bright, iridescent green, while the underparts are a greyish-white color. Adult males have a red spot on their throat, which is absent in females and juveniles.

Field

Identification

When observing the Bearded Mountaineer in the field, its distinctive bearded appearance and bright green upperparts make it easy to identify. However, it may sometimes be mistaken for similar species such as the Tyrian Metaltail and Sword-billed Hummingbird.

It is important to note that these species have different physical characteristics, such as the Sword-billed Hummingbird’s long bill and the Tyrian Metaltail’s metallic plumage.

Similar Species

The Tyrian Metaltail is similar to the Bearded Mountaineer in its size and overall appearance. However, it can be easily distinguished by its metallic plumage, which is a combination of green and purple.

The Sword-billed Hummingbird, on the other hand, is a larger bird with a distinctive, long bill that separates it from the Bearded Mountaineer.

Plumages

The Bearded Mountaineer undergoes two molts each year, which results in different plumages for the bird. The first molt occurs in the breeding season, while the second molt occurs in the non-breeding season.

The breeding plumage of the Bearded Mountaineer is characterized by its iridescent green upperparts and its red throat patch in males. Females and juveniles lack the red spot on their throats and have duller plumage.

During the non-breeding season, the Bearded Mountaineer’s plumage becomes duller and less iridescent, but it retains its bearded and striped facial markings.

Molts

The molting process of the Bearded Mountaineer involves the shedding and replacement of feathers. During the first molt, which takes place in the breeding season, the bird replaces its feathers in a sequence starting from the head and moving down the body.

In the second molt, which takes place in the non-breeding season, the feathers are replaced in the opposite direction, starting from the tail and moving up to the head. In conclusion, the Bearded Mountaineer is a unique and striking bird species that can be easily identified by its bearded appearance and iridescent green upperparts.

By understanding its physical characteristics, plumages, and molts, birdwatchers and nature enthusiasts alike can appreciate this remarkable creature even more.

Systematics History

The Bearded Mountaineer, also known as Oreonympha nobilis, is a member of the Trochilidae family of hummingbirds. The Trochilidae family is one of the largest avian families and includes more than 330 species of hummingbirds.

Oreonympha nobilis was first described by Gould in 1847 and was initially placed into its own genus, Oreonympha. Later, it was reclassified as Aglaiocercus nobilis before being placed back into Oreonympha.

Geographic Variation

The Bearded Mountaineer has a relatively limited range, being found only in the high Andean forests of South America. However, within this range, there is significant geographic variation in the species’ appearance, which has led to the recognition of multiple subspecies.

Subspecies

There are currently four recognized subspecies of the Bearded Mountaineer:

– Oreonympha nobilis nobilis: This subspecies is found in the Andes Mountains of Columbia and is the nominate subspecies. It has a brighter green upperpart and more pronounced stripes on the face compared to other subspecies.

– Oreonympha nobilis dilloniana: This subspecies is found in the Andes Mountains of Ecuador and Peru and has a more bronzy-green color to its upperparts compared to other subspecies. – Oreonympha nobilis chimborazo: Found in the Andes Mountains of Ecuador, this subspecies has dark blue-green feathers on the upperparts.

– Oreonympha nobilis consita: Found in the Andes Mountains of Peru, this subspecies has a paler green upperpart color and less distinct facial stripes compared to other subspecies.

Related Species

The Bearded Mountaineer is part of the genus Oreonympha, which also includes the Rufous-capped Thornbill (Oreonympha ruficoronata). The Rufous-capped Thornbill is distributed in northern Peru and has similar physical characteristics and habits to the Bearded Mountaineer, including feeding on nectar and insects.

Historical Changes to Distribution

The distribution of the Bearded Mountaineer has been influenced by a number of historical factors. During the last glacial period, the Andean mountains were covered in ice and snow, which led to a decrease in the populations of high-altitude organisms, including the Bearded Mountaineer.

Following the decline of the glaciers, some of the populations were able to expand to their current ranges. Human activities have also impacted the distribution of the Bearded Mountaineer.

In recent years, deforestation and habitat destruction have threatened the species’ survival. On the other hand, human settlements and agricultural practices have created new habitats for the species, such as gardens and fields, leading to an expansion of some populations.

Climate change is another factor that is likely to impact the distribution of the Bearded Mountaineer in the future. Global warming is causing a shift in temperature patterns, which may push the species to higher altitudes in search of cooler habitats.

This could potentially lead to a decrease in the size of the species’ range. Overall, the Bearded Mountaineer is a fascinating species that is acutely adapted to the unique ecological conditions of the Andean highland forests.

By understanding the systematics history, geographic variation, subspecies, and historical changes to distribution of the species, one can gain a deeper appreciation for this remarkable bird.

Habitat

The Bearded Mountaineer is found in the high altitude forests of the Andes Mountains of South America. Specifically, they are found in the cloud forests and humid montane forests of Colombia, Ecuador, and Peru.

These forests are characterized by moderate temperatures, high humidity, and frequent fog and mist. The Bearded Mountaineer prefers habitats with abundant flowering plants, as it feeds mainly on nectar and insects.

They are most commonly found at elevations between 2000 and 3500 meters (6561 to 11483 feet) above sea level. In their natural habitat, the Bearded Mountaineer is often seen perching on low branches and vines or hovering in front of a flower.

They are also known to visit hummingbird feeders in gardens and parks that are present at high altitudes. The Bearded Mountaineer is considered a habitat specialist as they are poorly adapted to habitat perturbations, such as deforestation, overgrazing, or mining.

Human activities that cause habitat destruction and fragmentation, such as agriculture, logging, and spread of urbanization, therefore pose a significant threat to their survival.

Movements and Migration

The Bearded Mountaineer is a non-migratory species, meaning that they do not undertake seasonal long-distance movements between different breeding and non-breeding ranges. However, there have been some reports of individuals being observed outside of their typical range, likely due to altitude changes driven by seasonal migration of flowering plants upon which they feed.

Like many hummingbird species, the Bearded Mountaineer has high energetic requirements, and therefore, it moves within its range to obtain food. During the dry season when flowering plants are sparse, the birds may move to more abundant sources of food, such as cloud forests and alpine meadows.

Some studies suggest that the Bearded Mountaineer demonstrates some degree of facultative altitudinal migration, which means that they may move up and down in altitude depending on the availability of food. For example, in the study conducted by Saboya and colleagues, the researchers observed that the Bearded Mountaineer moved from cloud forests at lower elevations to areas of higher elevation when flowering plants became available.

Despite their non-migratory behavior, the Bearded Mountaineer is adaptive to climate changes and the evolution of new breeding habitats. For example, some populations have undergone rapid evolutionary changes in beak morphology that allows them to exploit specific flowers and play a critical role in plant-pollinator relationships.

In conclusion, the Bearded Mountaineer is endemic to the high altitude forests of the Andes Mountains of South America, where they are found mainly between elevations of 2000 to 3500 meters. They are habitat specialists, meaning that they depend on intact high-altitude forest habitats for their survival.

Though relatively non-migratory, they do move within their range in search of food, and may experience facultative altitudinal migration. Understanding the movements, habitat, and range of the Bearded Mountaineer is essential to its conservation.

Diet and Foraging

Feeding

The Bearded Mountaineer is a nectarivorous bird that feeds primarily on the nectar of flowering plants. They also consume small insects and spiders, which provide an essential source of protein in their diet.

During foraging, they often perch on the stem of flowering plants or hover in front of the flower to consume the nectar. They use their long, straight bill to access the nectar hidden inside the flowers.

Diet

The Bearded Mountaineer’s diet consists mainly of nectar, which normally makes up around 90% of their food intake. They feed on a variety of flowering plant species, such as members of the Gesneriaceae and Ericaceae families.

They also consume small insects and spiders, which provide an essential source of protein in their diet and supplement their nutrition. The high reliance on nectar as a food source means that the survival of the bird relies on plant blooming cycles and the presence of flowering plants.

For this reason, the Bearded Mountaineer may follow flowering periods and move within its range for the availability and abundance of food.

Metabolism and Temperature Regulation

The Bearded Mountaineer has a high metabolic rate to meet the energetic requirements associated with its dietary and foraging behavior. They have been observed to feed for long periods to obtain the high-caloric value of nectar and compensate for the energy lost in hovering flight, which has high metabolic costs.

Bearded Mountaineers also have adaptations in their physiological systems to cope with cold temperatures. They are known to have a high metabolic rate that helps to generate heat, as well as behavioral adaptations such as roosting in protected places overnight that provides the bird with a favorable temperature environment.

Sounds and Vocal Behavior

Vocalizations

Like many hummingbirds, the Bearded Mountaineer is known for its vocalizations. Males produce a series of high-pitched, twittering sounds during displays to attract females.

These sounds are often accompanied by aerial maneuvers, such as quick darting and hovering flights, and during these displays, the males exhibit their bright and iridescent feathers. The Bearded Mountaineer’s vocalization often consists of long chirps or buzzing sounds lasting between 1 and 2 seconds and frequencies between 1500 and 8000 Hz.

In addition to mating displays, Bearded Mountaineers use vocalizations to defend their territory.

They produce a high-pitched, sharp, metallic trill to warn other male intruders that their territory is occupied. These trills can range from one to several seconds in duration.

Additionally, during flight, they also make a whirring sound created by the movement of their wings. In conclusion, the Bearded Mountaineer is truly adapted to life on the Andean highlands, where it feeds on nectar and insects and uses its adaptations in its metabolism and thermoregulation to maintain its high energetic requirements.

Their vocalizations also play a significant role in territorial defense and attracting mates. Overall, by understanding the bird’s diet and foraging behaviors and its vocalizations, bird lovers and researchers alike can develop a deeper appreciation for this remarkable species.

Behavior

Locomotion

The Bearded Mountaineer exhibits two primary modes of locomotion, including walking and hovering flight. During walking, they use their feet to move around and search for food.

However, the majority of their foraging behavior is performed through hovering in front of the flowers for extended periods while feeding on nectar.

Self Maintenance

Self-maintenance involves the simultaneous grooming and cleaning of feathers, which keeps the bird’s plumage in good condition. The Bearded Mountaineer is a meticulous groomer and performs this behavior by using its bill to preen its feathers, which also aids in removing small parasites and insects.

They also shake their feathers to remove dust and dirt.

Agonistic Behavior

The Bearded Mountaineer is also known to exhibit agonistic behavior towards other birds that enter its territory. This behavior usually involves high pitched vocalizations and sometimes physical interactions such as tail-feather displaying, aerial chases, and pecking movements.

Sexual Behavior

Male Bearded Mountaineers exhibit significant sexual behavior during the breeding season. They will compete for territories that have the most abundant food supply and perform vocal and aerial displays to attract females.

Females will choose the most attractive males based on the quality, location, and defense of their territory.

Breeding

Mating in the Bearded Mountaineer occurs during the breeding season, which usually runs from January to May in the southern hemisphere. During this period, males establish territories and defend them from other males.

They do so by vocal displays and physical confrontations. Female Bearded Mountaineers typically lay one egg per clutch and may produce up to two broods per season.

Once hatched, the young will be kept in the nest, where the female is responsible for the breeding and the feeding of the nestlings. They fledge within 20 to 24 days of hatching under normal conditions.

Demography and Populations

The Bearded Mountaineer is currently classified as a species of least concern by the International Union for Conservation of Nature (IUCN). However, it is essential to monitor its populations in the long term due to localized declines due to habitat loss and degradation in the wild.

Studies have shown that habitat fragmentation and degradation have a significant impact on the species’ population and breeding fitness. As the bird relies mainly on high-altitude forest habitats for its food supply, the lack of adequate breeding habitats could lead to limiting factors in both survival and reproduction.

The monitoring of population and range distributions of the species is essential to quantify the effects of climate changes on their demography and the impact of expanding human activities on the species’ survival. Long-term data provide the basis for making adequate management and conservation efforts to protect the Bearded Mountaineer and its habitats and ensure a sustainable future for the species.

In conclusion, Bearded Mountaineer exhibits unique behaviors such as territorial behavior, agonistic behavior, and sexual behavior during the breeding season. Understanding its natural behaviors helps understand the species’ biology and provide solutions for their management and conservation needs.

By understanding

Demography and Populations of the Bearded Mountaineer, we can identify potential threats to the species and act to conserve it. The Bearded Mountaineer is a fascinating bird species that is found exclusively in the high Andean forest habitats of South America.

This article addressed various aspects of the species, including its identification, range, subspecies, diet, vocalization, and behavior. Additionally, we covered the Bearded Mountaineer’s reproductive behavior and the importance of monitoring its populations in light of current threats to their habitats.

Understanding the intricate details about the biology and behavior of the Bearded Mountaineer is crucial to incite effective conservation policies and to promote awareness and appreciation of the species. The conservation of the Bearded Mountaineer is vital to ensure the protection of biodiversity and promote sustainable habitat management in the context of their ecological relationships.

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