This largely tropical and sub-tropical Old World family is quite large with 98 species, yet three-quarters of them belong to a single homogeneous genus (Zosterops), most members of which share olive-green upperparts, a yellow throat and a silvery-white ring of feathers around the eyes. They are small, warbler-like birds with a short, slender, almost straight bill, shortish, rounded wings, and slender but strong legs. White-eyes inhabit all wooded habitats, and are almost exclusively arboreal. They spend much of their time searching amongst foliage for insects and their larvae, and spiders, which are usually gleaned from leaves or twigs, or extracted from bark crevices. However these birds also take a great deal of fruit when available, and probe flowers of many kinds to extract the nectar, facilitated by the long, grooved tongue which has a brush tip for mopping up liquids. The latter is also a useful adaptation for extracting the juice and pulp from fruits that are too large or difficult to remove from the tree, after piercing the skin. The narrow openings of tubular flowers and rolled-up leaves are sometimes widened by inserting the bill, then opening the two mandibles. Highly gregarious, white-eyes often congregate into flocks that seem to be constantly on the move. Outside the breeding season these flocks can be very large, sometimes consisting of over 100 individuals. Moreover, they are frequently core members, and even leaders, of mixed-species foraging flocks. Flocks are persistently noisy as many individuals simultaneously give chicken-like chirping notes; but when in pairs they tedn to be quiet, except when the male sings, often including mimicry.
Java has five species, four of which are typical white-eyes (Zosterops), while the remaining one (Grey-throated Ibon) is endemic to Java and Bali, but restricted to mountains. Baluran has one species, but a second species may be an occasional visitor.