Fantails are small insectivorous birds of Australasia, Southeast Asia and the Indian subcontinent belonging to the genus Rhipidura in the family Rhipiduridae. Most of the species are about 15 to 18 cm long, specialist aerial feeders, and named as "fantails", but the Australian willie wagtail is a little larger, and, though still an expert hunter of insects on the wing, concentrates equally on terrestrial prey.
The true wagtails are part of the genus Motacilla in the family Motacillidae and are not close relatives of the fantails.
Fantails are an Australasian family that has spread from as far as Samoa to northern India. In the south the grey fantail ranges as far as The Snares off New Zealand, in the eastern extent of the family has several endemic forms in western Polynesia. There are numerous species in Indonesia, the Philippines and in South East Asia, and the family ranges into southern China, India and the Himalayas. Some species have a widespread distribution, particularly the willie wagtail, grey fantail, white-throated fantail and northern fantail; others have a highly restricted range and in the case of some insular species may be restricted to a single island. The Mussau fantail is restricted to a single island in the Bismarck Archipelago, and the Kadavu fantail has a similarly restricted distribution in the Kadavu Group of Fiji.
Most fantails, particularly the tropical or insular forms, are sedentary and undertake no migration. Some northern and southern species undertake a variety of movements; the yellow-bellied fantail of the Himalayas is an altitudinal migrant, breeding between 1500 and 4000 metres, but moving to lower altitudes (as low as 180 m) in the winter. Some Australian fantails undertake seasonal migrations, although these show considerable variation even within individual species. Most populations of the rufous fantail exhibit little migratory behaviour, but the south-eastern population moves en masse to northern Queensland and New Guinea.
Fantails exhibit wide tastes in habitat; while the majority of species are found in rainforests fantails exist in most available habitats from deserts and mangrove forests to highly modified agricultural and urban environments. Most species are able to survive in a variety of habitats. Of all the species the mangrove fantail has the most restricted habitat requirements, being entirely restricted to mangrove forests over some of its range, although it can exist 3 km away in the absence of other fantails. Some of the more primitive species are generally more restricted to primary rainforest, but most other species can survive in more disturbed forest. The most adaptable species is the willie wagtail, which is abundant in every habitat type in Australia except for dense rainforest.