What is "tree kingfisher"

n. the most numerous family, ''Halcyonidae'', of kingfishers; they are widely distributed in Africa, Asia and Australia

The tree kingfishers or wood kingfishers, subfamily Halcyoninae, are the most numerous of the three families of birds in the kingfisher group, with between 56 and 61 species in around 12 genera, including several species of kookaburras. The family appears to have arisen in Indochina and Maritime Southeast Asia and then spread to many areas around the world. Tree kingfishers are widespread through Asia and Australasia, but also appear in Africa and the islands of the Pacific and Indian Oceans, using a range of habitats from tropical rainforest to open woodlands.

The tree kingfishers are short-tailed, large-headed, compact birds with long, pointed bills. Like other Coraciiformes, they are brightly coloured. Most are monogamous and territorial, nesting in holes in trees or termite nests. Both parents incubate the eggs and feed the chicks. Although some tree kingfishers frequent wetlands, none are specialist fish-eaters. Most species dive onto prey from a perch, mainly taking slow-moving invertebrates or small vertebrates.