Sunbirds

Sunbirds are 105 species of small, lovely birds that make up the family Nectariniidae. Sunbirds occur in Africa, South and Southeast Asia, New Guinea, and Australia. They occupy a wide range of habitats, from forests and savannas to shrubby grasslands, and some agricultural habitats.

Sunbirds range in body length from 4-9 in (9-22 cm). The wings are short and rounded, and the tail is quite long in some species. They have a long, pointed, down-curved beak, which in some species exceeds the length of the head. The tongue is long, tubular for about two-thirds of its length, and its tip is split. The unusual bill and tongue of sunbirds are adaptations to feeding on the nectar of flowers. There are fine serrations near the tip of the beak, which are thought to be an adaptation to gripping insects.

Male sunbirds are brightly and garishly colored in bold patterns of green, blue, purple, red, black, or white. Many of these superb hues are due to a iridescence of the feathers, which is a prism-like, physical phenomenon, rather than the color of pigments. Female sunbirds are more subdued in their coloration, and are not iridescent. The sunbirds and hummingbirds (family Trochilidae) are not related, but they are similar in aspects of their iridescent coloration, and their feeding.

Sunbirds are active, strongly flying birds. They mostly feed on nectar, and also on insects. Sunbirds sometimes hover while feeding.

Sunbird nests are hanging, purselike structures, with a side entrance. The nest is constructed by the female of fibrous plant materials, partly held together using spider webs. The one to three eggs are incubated mostly by the female, but she is fed by the male while on the nest. Both parents care for the babies, which have a straight bill when born.

There are 78 species of sunbirds in the genus Nectarinia. Males of the superb sunbird (Nectarinia superba) of central Africa have a metallic-green back, a purple throat, and a burgundy breast, with black wings and tail. Clearly, this bird is appropriately named. Males of Gould's sunbird (Aethopyga gouldiae) of Southeast Asia have a blue head and tail, a crimson back, scarlet breast, and a lemon-yellow belly.

The spiderhunters (Arachnothera spp.) are greenish, less-garishly colored birds, and they have very long bills. The long-billed spiderhunter (Arachnothera rubusta) of Indochina and Southeast Asia is a spider- and insect-eating bird that inhabits montane forests.