Bulbuls are about 120 species of medium-sized, perching birds, distributed among 15 genera, and making up the family Pyncnontidae. The most diverse genus is Pycnonotus, with about 50 species. Bulbuls are mostly tropical and subtropical birds, occurring in Africa, Asia, and Southeast Asia. Some relatively northern species are migratory, but most species of bulbuls are local birds.
Bulbuls have rather short, rounded wings, a long tail, small, relatively delicate legs and feet, a small, slender bill, and prominent bristles about the base of the top mandible (these are known as rictal bristles). The body size of bulbuls ranges from 6-11 in (15-28 cm).
The coloration of bulbul species is commonly black or grey, often with reddish markings, and sometimes with a distinctive crest on the top of the head. Male and female birds look very similar, as do juvenile birds, although their coloration is more subdued than that of adults.
Bulbuls build a cup-shaped nest in a bush or tree, and lay two to four eggs. Both parents share in the incubation and care of the young.
Species of bulbuls occur in diverse tropical habitats, but not in deserts. They may occur in dense vegetation in tropical forests or in more open habitats, such as gardens in towns or even city parks. Some species of bulbuls are accomplished singers, and they are among the more pleasing avian vocalists in tropical towns and parks where habitat is available for these birds.
Most species of bulbuls eat small fruits, but they may also feed on insects, particularly when they are raising babies, which require high-protein foods. Both parents feed and care for the young, which typically fledge about two weeks after hatching. During the non-breeding season, bulbuls often occur in mixed-species flocks with other bulbuls, and sometimes with birds of other families.
The black bulbul (Hypsipetes madagascariensis) is a wide-ranging species, occurring in young forests and other disturbed habitats from Madagascar to Southeast Asia. This species has an all-black plumage, but red legs, feet, bill, and eyes.
The red-whiskered bulbul (Pycnonotus jocosus) is a common and familiar species of open habitats from India, through south China, to mainland Southeast Asia. This distinctively head-crested species has also been introduced to Australia, Mauritius, Fiji, and southern Florida.
The yellow-crowned bulbul (Pycnonotus zeylanicus) of Malaya, Borneo, Sumatra, and Java is an especially accomplished singer, and is sometimes kept in that region as a caged songbird.