Bird O'clock

Discovering the Fascinating Black-Eared Cuckoo: Plumages Migration and Behavior

Have you ever heard of the Black-eared Cuckoo? This bird species is one of the most intriguing birds found in tropical and subtropical regions of Southeast Asia.

The Black-eared Cuckoo, scientifically known as Chrysococcyx osculans, is a member of the cuckoo family and is commonly spotted in forests and woodland habitat. In this article, we will explore the identification, plumages, and molts of this bird species.

Identification:

Field Identification:

The Black-eared Cuckoo is a small bird, measuring about 16-17 cm (6.5 inches) in length and weighing around 25-30 grams. It has a brownish-black plumage with a distinctive black ear patch that starts from the head and runs to the neck.

The chest and the belly of the bird are white, while the tail is very long and pointed. The bill is greenish-yellow, long, and thin.

Similar Species:

The Black-eared Cuckoo has a close resemblance to Asian Emerald Cuckoo and Little Bronze Cuckoo in terms of plumage and overall size. However, the Black-eared Cuckoo can be distinguished by its distinctive black ear patch, long and pointed tail, and the greenish-yellow bill.

Plumages:

The Black-eared Cuckoo has two distinctive plumages- breeding and non-breeding. The breeding plumage is a dull greenish-black color with a bright yellow patch on the chest.

The non-breeding adult’s plumage is a dull brownish-black with a brownish patch on the chest. Juvenile birds have a reddish-brown plumage with a whitish throat and belly.

Molts:

Molting is the process of shedding feather and growing new feathers in birds. The Black-eared Cuckoo goes through a prealternate molt and alternate molt.

The prealternate molt happens between December and March, where adult males grow a new breeding plumage that helps them attract females. The alternate molt occurs once the breeding season is over, and the birds change their plumage from breeding to non-breeding.

The alternate molt is usually incomplete and takes place during September and October. Conclusion:

The Black-eared Cuckoo is one of the most intriguing bird species, found in the tropical and subtropical regions of Southeast Asia.

With its distinct plumages and molts, it’s a fascinating bird to study. This article has explored the identification, plumages, and molts of this bird species, its close resemblance to the Asian Emerald Cuckoo and Little Bronze Cuckoo, and its distinctive features such as its long and pointed tail, greenish-yellow bill, and black ear patch.

By knowing more about the Black-eared Cuckoo, we can appreciate the beauty and biodiversity of our environment. Systematics History:

The Black-eared Cuckoo, also known as Chrysococcyx osculans, belongs to the family Cuculidae, which comprises of cuckoos, coucals, and anis.

This bird was first described by Henri Milne Edwards in 1868. The species name “osculans” comes from the Latin word “osculare,” which means to kiss, referring to the kissing sound of the bird’s call.

Geographic Variation:

The Black-eared Cuckoo is a widely distributed species found in Southeast Asia, including Cambodia, China, Indonesia, Laos, Malaysia, Myanmar, Thailand, and Vietnam. The species occupies different habitats, including forests, woodlands, and plantations.

The bird is migratory, and populations of the species move from breeding to non-breeding areas, depending on the time of the year. Subspecies:

The Black-eared Cuckoo has three known subspecies- Chrysococcyx osculans osculans, Chrysococcyx osculans yamakanensis, and Chrysococcyx osculans klossi.

Each of these subspecies differs slightly in plumage and usually occupies different geographical regions. – Chrysococcyx osculans osculans:

This subspecies is found in southern China and northern Vietnam.

The bird’s breeding plumage is dark greenish-black, with a yellow patch on the breast. This subspecies has a distinctive, broad black ear patch and white throat patch that extends to the ear patch.

– Chrysococcyx osculans yamakanensis:

This subspecies is found in Taiwan, the Ryukyu Islands, and the Nansei Islands. The bird’s breeding plumage is dark greenish-black, with a bright yellow patch on the breast.

This subspecies has a somewhat narrow black ear patch that does not extend to the neck, and a white throat patch that does not extend to the ear patch. – Chrysococcyx osculans klossi:

This subspecies is found in western and southern Sumatra.

The bird’s breeding plumage is darker than the other two subspecies, and it has a smaller yellow patch on the breast. This subspecies also has a distinct black ear patch and a white throat patch, but the ear patch is narrower than the other subspecies.

Related Species:

The Black-eared Cuckoo is part of the Chrysococcyx genus, which consists of 14 species worldwide. The genus is characterized by its brood parasitic behavior, where the birds lay their eggs in the nests of other species.

The bird species related to the Black-eared Cuckoo include:

– Violet Cuckoo (Chrysococcyx xanthorhynchus)

– Lesser Cuckoo (Cuculus poliocephalus)

– Himalayan Cuckoo (Cuculus saturatus)

– Oriental Cuckoo (Cuculus optatus)

Historical Changes to Distribution:

The Black-eared Cuckoo has been widely distributed throughout Southeast Asia since the 19th century. However, human activities and habitat loss have affected the species’ population and distribution.

Today, the bird’s population is fragmented and confined to small pockets of suitable habitat. Historically, the species was once distributed throughout the region, including areas such as the Malay Peninsula, Sumatra, and Borneo.

However, deforestation, urbanization, and habitat fragmentation have resulted in the bird’s disappearance from many areas, especially in the Borneo region. In recent years, conservation initiatives have been implemented to restore the species’ distribution and population.

These efforts include habitat protection, reforestation, and research on the bird’s ecology and behavior. In some areas where the bird has locally disappeared, nesting boxes have been deployed to improve breeding success.

Conclusion:

The Black-eared Cuckoo is a fascinating species that has captured the attention of scientists and bird enthusiasts for many years. The bird’s wide distribution, subspecies, and related species have helped us understand its systematics and evolutionary history.

However, human activities have significantly impacted the bird’s population and distribution, leading to the need for conservation measures to rescue the species. By understanding the historical changes in the bird’s distribution, we can better appreciate its ecological significance and work towards its preservation.

Habitat:

The Black-eared Cuckoo is a forest bird that inhabits tropical and subtropical regions. The bird is distributed in Southeast Asia, including Cambodia, China, Indonesia, Laos, Malaysia, Myanmar, Thailand, and Vietnam.

The species is commonly found in primary and secondary forests, forest edges, open woodlands, and plantations. The Black-eared Cuckoo requires forest cover for its breeding and nesting habitat, as it relies on rich and diverse insect populations found in these areas.

The birds diet consists mainly of insects such as beetles, caterpillars, and cicadas, making these forests an essential habitat for the species. They also feed on berries and fruits during non-breeding periods.

Deforestation, habitat fragmentation, and land-use changes have negatively impacted the bird’s population and breeding success. As a result, conservation initiatives to protect and restore the birds habitat have been initiated in several areas, including reforestation programs, habitat restoration, and establishment of forest reserves and protected areas.

Movements and Migration:

The Black-eared Cuckoo is a migratory bird that moves between its breeding and non-breeding areas, depending on the time of the year. During breeding season, which occurs from March to July, the bird occupies its breeding grounds and establishes its territories.

The breeding range of the Black-eared Cuckoo varies depending on the subspecies; for instance, some subspecies breed in southern China and northern Vietnam, while others breed in Taiwan and the Ryukyu Islands. After breeding, the birds undergo a molt and begin their migration to their non-breeding grounds.

The non-breeding grounds are typically located in Indonesia, Malaysia, and the Philippines. The bird’s migration route and habits are not well understood, as they tend to be solitary and inconspicuous during migration.

The exact timing of the bird’s migration varies depending on the breeding area and local environmental conditions. For example, in Taiwan, breeding birds begin to migrate southwards from September to October, while in southern China and northern Vietnam, breeding birds begin to migrate from November to December.

Black-eared Cuckoos migrate mainly at night, and it is believed that they use celestial navigation to guide them during their migration routes. The birds’ migration has been observed to take place in a series of short hops, with periods of rest and feeding in between.

The birds’ migration is affected by various factors such as habitat degradation, hunting, and climate change. Conclusion:

The Black-eared Cuckoo is a migratory bird that requires forest cover for its breeding and nesting habitat.

The bird starts breeding from March to July and usually migrates to its non-breeding areas in Indonesia, Malaysia, and the Philippines. Deforestation, habitat fragmentation, and land-use changes have severely impacted their population and breeding success, leading to conservation initiatives to protect and restore their habitat.

Understanding the migration habits and routes of the Black-eared Cuckoo is important in the conservation of the species and its overall ecological significance. Diet and Foraging:

Feeding:

The Black-eared Cuckoo is an insectivorous species that feeds on a variety of insects, including caterpillars, beetles, and cicadas.

During the breeding season, they rely heavily on insect populations to feed their young, whereas during the non-breeding season, they supplement their diet with fruits and berries. Diet:

The Black-eared Cuckoo has a specialized diet that consists mainly of insects.

The bird’s slender, decurved beak allows them to extract insects from bark crevices, branches, and leaves. They use their bills to pry open the bark of trees and feed on insect larvae and pupae.

They can also forage for insects on the ground. During the non-breeding season, the bird feeds on fruits and berries, which are an essential source of carbohydrates.

They predominantly feed on forest fruits such as figs, berries, and wild fruits. However, their diet varies depending on the locality and season.

Metabolism and Temperature Regulation:

The Black-eared Cuckoo maintains a high metabolic rate, which is necessary for their active lifestyle and ability to catch insects while on the wing. They are endothermic, which means that they are capable of regulating their body temperature and maintaining a stable body temperature despite changes in the external environment.

The bird’s circulatory system plays a central role in regulating their body temperature. The blood vessels in their legs and feet are arranged in a counter-current heat exchange system, which helps to conserve body heat when in cold environments.

Meanwhile, the bird’s high metabolic rate generates a lot of internal heat, which is dissipated through their skin and respiratory system. Sounds and Vocal Behavior:

Vocalization:

The Black-eared Cuckoo has a distinctive and melodious vocalization, which consists of a series of three-syllable notes.

The bird’s call is usually soft and musical, with a “poop-poop-poop” or “pip-pip-pip” sound. The bird’s call is most active during the breeding season and is used for territorial defense, courtship, and communication among members of a group.

The male Black-eared Cuckoo produces a distinct call during the breeding period, which is used to attract mates. The call is usually high-pitched and starts with a series of “ka-ka” notes, followed by several short, high-pitched whistles.

The female Black-eared Cuckoo has a distinct call that is used to communicate with their young. The call is usually soft and consists of a series of ascending and descending notes.

Apart from the bird’s natural vocalizations, Black-eared Cuckoos also imitate the sounds of other birds. This behavior is known as mimicry and is used to deceive and distract potential predators or to attract prey.

Conclusion:

The Black-eared Cuckoo has a specialized insect-based diet, which allows them to extract insects from bark crevices and branches. During the non-breeding season, the bird supplements their diet with fruits and berries.

The Black-eared Cuckoo is endothermic, which means that they maintain a stable body temperature through regulation of their circulatory system. The bird’s vocalization is a crucial aspect of its survival, as it is used for territorial defense, courtship, and communication.

The Black-eared Cuckoo has a melodious and distinct call that is used during the breeding season, while the female Black-eared Cuckoo has a softer call used to communicate with their young. In addition, mimicry is also a behavioral adaptation used by the Black-eared Cuckoo to deceive and distract potential predators or to attract prey.

Understanding the dietary and vocal behavior of the Black-eared Cuckoo is crucial in conservation efforts and increasing our knowledge of their ecological significance. Behavior:

Locomotion:

The Black-eared Cuckoo is a quick, agile flyer that is capable of catching insects while in flight.

They have a swift and wavering flight pattern, which allows them to maneuver easily in the dense forest canopy. The bird’s slender, decurved beak and long tail also aid in their locomotion.

Self Maintenance:

The Black-eared Cuckoo engages in grooming behavior as a way of maintaining its feathers and keeping them in good condition. They use their bills to preen and clean their feathers, which helps to remove dirt, debris, and parasites.

The bird’s preening also helps to distribute oil from their preen gland, which is essential for keeping their feathers water-resistant. Agonistic Behavior:

The Black-eared Cuckoo exhibits both aggressive and submissive behavior, depending on the situation.

They engage in aggressive behavior when defending their territories or when competing for limited resources such as food or nesting sites. This behavior includes loud vocalization and physical aggression.

When faced with a dominant bird, the Black-eared Cuckoo will often adopt submissive behavior, which includes a lowered head and body posture. This behavior helps to reduce the risk of injury and avoid conflict.

Sexual Behavior:

The Black-eared Cuckoo is a monogamous species, and pair formation occurs during the breeding season. The breeding pairs establish territories, which they defend aggressively against other cuckoos and potential predators.

During the breeding season, the male Black-eared Cuckoo engages in courtship behavior, which includes vocalization and displays such as wing spreading. The male also feeds the female during courtship, which serves as a demonstration of his ability to provide for her and their offspring.

Breeding:

The Black-eared Cuckoo breeds during the rainy season, which occurs from March to July. They are cavity nesters and use natural tree hollows or abandoned woodpecker nests as their nesting sites.

The female Black-eared Cuckoo lays one or two eggs that are white and spotted with brown. The eggs are incubated by both the male and female for about 14-16 days.

After hatching, the chicks are fed mainly on insects, with both parents taking turns feeding them. The chicks fledge at around 20 days, after which they become independent from their parents.

The Black-eared Cuckoo is known to exhibit brood parasitism, wherein a female lays her eggs in the nests of other bird species, allowing the other bird species to raise her chicks. Demography and Populations:

The Black-eared Cuckoo is a widespread species found in Southeast Asia.

However, the bird’s populations have undergone significant declines in recent years due to habitat loss and degradation. As a result, the species is now listed as Near Threatened on the International Union for Conservation of Nature Red List of Threatened Species.

Conservation initiatives have been implemented to protect and restore the bird’s habitat and population. These initiatives include habitat protection, reforestation, and research on the bird’s ecology and behavior.

In addition, education and awareness programs have been established to promote the significance of the Black-eared Cuckoo and its role in the ecosystem. Conclusion:

The Black-eared Cuckoo is an agile and quick flyer that is capable of catching insects while in flight.

The bird exhibits grooming behavior, aggressive and submissive behavior, and monogamous sexual behavior. During the breeding season, the bird lays one or two eggs, which are incubated by both the male and female for around 14-16 days.

The chicks are fed on insects and become independent around 20 days after hatching. Conservation initiatives are necessary to protect the species, which has undergone significant declines due to habitat loss and degradation.

By understanding the bird’s behavior, breeding habits, and

Popular Posts