Kingfishers | ||||||||||
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Belted Kingfisher
(Ceryle alcyon) |
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Scientific classification | ||||||||||
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Alcedinidae Halcyonidae Cerylidae |
Kingfishers are birds of the three families Alcedinidae (river kingfishers), Halcyonidae (tree kingfishers), and Cerylidae (water kingfishers). There are about 90 species of kingfisher. All have large heads, long, sharp, pointed bills, short legs, and stubby tails. They are found throughout the world.
The taxonomy of the three families is complex and rather controversial. Although commonly assigned to the order Coraciiformes, from this level down confusion sets in.
The kingfishers were traditionally treated as one family, Alcedinidae with three subfamilies, but following the 1990s revolution in bird taxonomy, the three former subfamilies are now usually elevated to familial level; a move supported by chromosome and DNA-DNA hybridisation studies, but challenged on the grounds that all three groups are monophyletic with respect to the other Coraciiformes; which leads to them being grouped as the suborder Alcedines.
The tree kingfishers have been previously given the familial name Dacelonidae but Halcyonidae has priority. This group derives from a very ancient divergence from the ancestral stock.
Kingfishers live in both woodland and wetland habitats. The Laughing Kookaburra, at 45 cm the world's largest kingfisher, is a woodland bird, while the European Kingfisher Alcedo atthis is always found near fresh water.
Kingfishers that live near water hunt small fish by diving. They also eat crayfish, frogs, and insects. Wood kingfishers eat reptiles. Kingfishers of all three families beat their prey to death, either by whipping it against a tree or by dropping it on a stone.
They are able to see well both in air and under water. To do this, their eyes have evolved an egg-shaped lens able to focus in the two different environments.
The Old World tropics and Australasia are the core area for this group. Europe and North America north of Mexico are very poorly represented with only one common kingfisher (European and Belted Kingfishers respectively), and a couple of uncommon or very local species each: (Ringed Kingfisher and Green Kingfisher in south Texas, Pied Kingfisher and White-breasted Kingfisher in SE Europe).
Even tropical South America has only five species plus wintering Belted Kingfisher. In comparison, the tiny African country of The Gambia has eight resident species in its 120 by 20 mile area.
The six species occurring in the Americas are four closely related green kingfishers in the genus Chloroceryle and two large crested kingfishers in the genus Megaceryle, suggesting that the sparse representation in the western hemisphere evolved from just one or two original colonising species.
External links
- ARKive - images and movies of the kingfisher (Alcedo atthis)
- Kingfisher videos on the Internet Bird Collection