Despite being a slightly bigger family (56 species) than the previous one (Rhipiduridae) with a greater diversity of size, form and colour, the whistlers have an even more restricted global distribution, being largely confined to New Guinea, Australia and Wallacea. Only four species have crossed Wallace’s Line, and one of these (featured here) extends as far as Southeast India. As their name implies, the whistlers are best known for their powerful, melodious whistled songs, which often end suddenly with a whipcrack note. They are robust, relatively big-headed birds with a stout, shrike-like bill and short rictal bristles. The legs are moderately long and the feet strong, useful for species which forage on the ground. Most whistlers, however, are canopy and mid-stage dwellers, that spend much time sitting sedately on a horizontal branch while peering intently at the undersides of leaves above them, before leaping to another perch or hopping along the branch to another vantage point. Insects are usually captured by gleaning and snatching, as whistlers rarely hawk or sally in the manner of flycatchers, monarchs and fantails. The majority of species are sexually dimorphic to some degree, though in several species (such as the Mangrove Whistler) the male has dull female-like plumage. Juveniles are unspotted and often mainly rufous in coloration.
Two species occur in Java, one of which (Golden Whistler P. pectoralis) is among the most variable songbirds in the world, with 59 currently recognised races spread between Fiji and mountains in East Java. The other species, found in Baluran, is much more widespread.