Andaman Serpent-Eagle
Spilornis elgini
A relatively small, uniformly dark brown eagle with a contrasting bright-yellow bare patch between the eye and the bill. The underparts are speckled with small white spots. In flight, the wings have narrow black-and-white bands and the tail has thick black bands. Juvenile similar to adult, but with a pale, cream-colored head. Often seen perched in trees under the canopy, from where it watches for small prey. Calls delivered in a series of 4-5 short, chirp-like whistles.
识别特征
The call of the Andaman serpent eagle consists of three to four short chip-sounding whistles. These birds are nearly entirely dark brown, except for their bright yellow faces and legs and they have spots on the tops of their wings and on their chests. They also have thick black bands on their tails and white and black bands on the underside of their wings. This species also has a hooked beak which is characteristic of a bird of prey and is used to tear apart food. Juvenile Andaman serpent eagles are known to have lighter colouring than adults and they also have a white head. Additionally, there is no sexual dimorphism between males and females, which means that it is impossible to differentiate the two sexes by physical characteristics alone.
分类信息
The genus Spilornis contains six species of serpent eagles, majority of which are island endemics. Serpent eagles are considered Old World birds because they are mostly found in Asia and Africa. In terms of taxonomy, the Andaman serpent eagle was originally thought to be a subspecies of Spilornis cheela before it was determined to be its own species. Since there is no complete taxonomic record for all of the species within Spilornis, it is difficult to determine exact relationships, although it is believed that the Andaman serpent eagle is an out group from the other Spilornis species. This means that the other Spilornis species are more closely related to each other than they are to the Andaman species. However, overall, even though they exhibit some variation, it has been determined that, because they are solely found in the Old World and mostly found on islands and in similar habitats, the species within Spilornis have very little genetic variation between them. This, along with the fact that they inhabit very similar territories, may explain why all of the species within the serpent eagle genus display very similar physical characteristics.
- 学名
- Spilornis elgini
- 命名信息
- (Blyth, 1863)
- 目
- Accipitriformes
- 科
- Accipitridae
- 属
- Spilornis
分布与栖息地
The Andaman archipelago includes 204 islands, majority of which are forested, that all surround three main large islands. The Andaman serpent eagle has been found on all of the Andaman Islands, even on the islands with as little area as 0.8 km2 , although they prefer larger ones, and have even been known to occupy two different islands at the same time. They are usually found inland in closed canopy evergreen forests, on hillsides and in tropical lowland areas, however they can also be found closer to the coast and on agricultural land. Additionally, this species uses mangrove marshes and creeks as nesting sites. Thus, they have some very specific habitat requirements that need to be met in order to successfully reproduce and these areas are currently being disturbed, which is threatening the species.<p>In terms of population density, the Andaman serpent eagle is common within the archipelago it is endemic to, but its population size is actually quite small with fewer than 4000 individuals that are spread amongst various subpopulations. Individuals within this species tend to have a lifespan of 8 years.
- 迁徙
- Resident species
行为
Migration pattern: Resident species.
保护状况
Population trend: declining.
- 种群趋势
- declining
照片
分布
鸟叫声
其他鸟类
Great Curassow
Crax rubra
Very large game bird of tropical forest, eliminated from most areas by hunting. Rarely found except in protected parks or very remote areas. Usually seen on the forest floor, singly or in small groups, but also feeds in trees. Males often sing from high in canopy: song is a very low-pitched, almost subliminal, booming sound. Not likely to be confused if seen well. Both sexes have distinctive curly crest. Female plumage is variable: some have bold barring, others have darker and mostly unbarred plumage.
Golden-crowned Kinglet
Regulus satrapa
Tiny, hyperactive songbird usually found in conifer trees. Look for black stripes on the head and bold wing pattern. The namesake golden crown is usually just a small stripe, but can be flared into an expressive fiery-orange crest when agitated. Breeds in coniferous forests, usually staying high in trees. In migration and winter, often joins mixed flocks of other songbirds in a wider variety of wooded habitats. Very active; often hovers and flicks wings as it forages. Listen for extremely high-pitched call notes.
Streak-headed Honeyeater
Pycnopygius stictocephalus
A medium-sized honeyeater of lowland and foothill forest edge and gardens. Upperparts dark brown and lower parts gray-brown. Dark head has thin white streaking on the crown and a distinctive white stripe on the face. Thought to mimic the appearance of the New Guinea Friarbird, but Streak-headed Honeyeater is much smaller. Also similar to the juvenile Brown Oriole, but Streak-headed Honeyeater lacks the streaking on the throated and chest. Varied vocalizations including series of repeated notes or strong, whistled, short phrases.
开始您的观鸟之旅
在户外识别鸟类，并在下一次观察时随手查阅鸟类图鉴。