About Leptocoma calcostetha (Jardine, 1843)
Leptocoma calcostetha, commonly known as the copper-throated sunbird, is a small bird species that ranges from 12.2 to 13 cm in length. For mature individuals, the average wingspan is 57.5mm, and the average tail length is 45.5mm. Adult males are predominantly black, with contrasting shimmering green markings on the head, shoulders, upper back, and rump. They have a copper-colored throat bordered by an outer ring of shimmering purplish-blue that extends down to the chest. They have black legs, black eyes with no eye ring, a down-curved black beak, and yellow pectoral tufts concealed beneath the wing; these last two traits are shared by many other species in the Nectariniidae (sunbird) family. Adult females also have black legs and a down-curved black beak, but their eyes have an incomplete white eye ring. Females have olive-yellow undersides and grayish-olive upper backs. They lack the species' iconic copper throat, which is replaced by a grayish-white color that contrasts with their gray heads. Juveniles resemble females, but have a yellow throat instead of grayish-white, with occasional dark scaling. The copper-throated sunbird is distributed across southeastern Asia, and can be found in Singapore, Vietnam, Malaysia, the Philippines, Myanmar, Cambodia, and western Indonesia, specifically Java Island. This species lives predominantly in coastal areas year-round, rather than far inland. It occupies both artificial and forest habitat types. Its artificial habitats include plantations, coconut groves, and rural gardens. Its forest habitats include tropical lowlands, tropical mangroves, heath forests, and alluvial forests. It is often found in flowering shrubs or trees, and typically stays in the upper-middle stories of the canopy. As a nectarivore, this species and most other sunbirds are important pollinators in their ecosystems. When collecting nectar, parts of the bird's body brush against the flower's anthers, the male sexual organs that release pollen. As the bird travels between different flowers, it carries pollen directly to other flowers' female sexual organs, fertilizing the plant. In some cases, documented observations show that sunbirds can cause reduced plant reproductive success. Birds often damage the flowers' reproductive organs, ruining the flower's chance of being fertilized. For this species, egg laying starts as early as January and ends as late as July. The typical clutch size is 2 eggs. The eggs are grayish-brown with dark spots. Nestlings typically hatch around July. Nest building is a cooperative activity done by both the male and female. The nest is a loosely woven pear-shaped structure built from fine grass, fibers, and hairs, which provides camouflage against bark and leaves. It has a solid base and an oval entrance with an overhang. Parents occasionally build decoy nests, most likely to confuse predators and brood parasites such as cuckoos. Cuckoo species are brood parasites that often target sunbird nests in Eastern Asia and Africa.
