The
river kingfishers or
Alcedinidae, are one of the three
families of
bird in the
kingfishergroup. The Alcedinidae once included all kingfishers, before the widespread recognition of
Halcyonidae (tree-kingfishers) and
Cerylidae (water-kingfishers). The family is widespread through
Africa, through east and south
Asia as far as
Australia, with one species, the
Common Kingfisher(
Alcedo atthis) also appearing in
Europe and northern Asia. The origin of the family is thought to have been in Asia.
These are brightly plumaged compact birds with short tails, large heads and long
bills. They feed on
insects or
fish, and lay white eggs in a self-excavated
burrow. Both adults incubate the
eggs and feed the chicks.
Taxonomy
The river kingfishers family Alcedinidae is one of nine in the order
Coraciiformes, which also includes the
motmots,
bee-eaters,
todies,
rollers,
ground-rollers,
Cuckoo Roller and two other families of
kingfishers. The rollers do not appear to be particularly closely related to the others groups, and the Coraciiformes are therefore probably
polyphyletic. In the past, all kingfishers were placed in the Alcedinidae, but it became clear that the three subfamilies diverged early, and the Halcyonidae (tree kingfisher|tree kingfishers) and Cerylidae (water kingfishers) are usually now treated as full families, with the Alcedinidae as the
basal lineage in the kingfisher clade.
The taxonomy of the family is uncertain at present: it includes 22 to 24 species in two to four genera. The uncertainty arises from two small African species. The
African Dwarf Kingfisher is sometimes placed in the monospecific genus
Myioceyx, and sometimes with the Pygmy Kingfishers in
Ispidina. However,
molecular analysis suggests that the
Madagascar Pygmy Kingfisher is most closely related to the
Malachite Kingfisher, and that the present arrangement into
Alcedo and
Ceyx may need to be reviewed as it seems not to reflect the actual relationships (for example, the
Azure Kingfisher is closer to
Ceyx erithacus).
| Species in taxonomic sequence |
| Common name | Binomial |
|---|
| Genus Alcedo |
|
| Blyth's Kingfisher | Alcedo hercules |
| Common Kingfisher | Alcedo atthis |
| Half-collared Kingfisher | Alcedo semitorquata |
| Shining Blue Kingfisher | Alcedo quadribrachys |
| Blue-eared Kingfisher | Alcedo meninting |
| Azure Kingfisher | Alcedo azurea |
| Bismarck Kingfisher | Alcedo websteri |
| Blue-banded Kingfisher | Alcedo euryzona |
| Indigo-banded Kingfisher | Alcedo cyanopecta |
| Silvery Kingfisher | Alcedo argentata |
| Malachite Kingfisher | Alcedo cristata |
| Madagascar Malachite Kingfisher | Alcedo vintsioides |
| White-bellied Kingfisher | Alcedo leucogaster |
| Cerulean Kingfisher | Alcedo coerulescens |
| Little Kingfisher | Alcedo pusilla |
| Príncipe Kingfisher | Alcedo nais |
| São Tomé Kingfisher | Alcedo thomensis |
| Genus Ceyx |
|
| Oriental Dwarf Kingfisher | Ceyx erithacus |
| Philippine Dwarf Kingfisher | Ceyx melanurus |
| Sulawesi Dwarf Kingfisher | Ceyx fallax |
| Rufous-backed Kingfisher | Ceyx rufidorsa |
| Variable Dwarf Kingfisher | Ceyx lepidus |
| Genus Ispidina |
|
| Madagascar Pygmy Kingfisher | Ispidina madagascariensis |
| African Pygmy Kingfisher | Ispidina picta |
| African Dwarf Kingfisher | Ispidina lecontei |
Description
All kingfishers are short-tailed large-headed compact birds with long pointed bills. Like other Coraciiformes, they are brightly coloured.
Alcedo species typically have metallic blue upperparts and head, and orange or white underparts. The sexes may be identical, as with
Bismarck Kingfisher, but most species show some
sexual dimorphism, ranging from a different bill colour as with Common Kingfisher to a completely different appearance. The male
Blue-banded Kingfisherhas white underparts with a blue breast band, whereas the female has orange underparts.
The small kingfishers that make up the rest of the family have blue or orange upperparts and white or buff underparts, and show little sexual variation. Across the family, the bill colour is linked to diet. The insectivorous species have red bills, and the fish-eaters have black bills.
When perched, kingfishers sit quite upright, and the flight is fast and direct. The call is typically a simple high-pitched squeak, often given in flight.
Distribution and habitat
Oriental Dwarf Kingfisher
Most alcedinids are found in the warm climates of Africa and southern and southeast Asia. Three species reach Australia, but only the
Common Kingfisher is found across most of Europe and temperate Asia. No members of this family are found in the Americas, although the
American green kingfishers are believed to have derived from alcedinid stock. The origin of the family is thought to have been in southern Asia, which still has the most species.
The Ceyx and Ispidina species are mainly birds of wet rainforest or other woodland, and are not necessarily associated with water. The Alcedo kingfishers are usually closely associated with fresh water, often in open habitats although some are primarily forest birds.
Behaviour
Breeding
River kingfishers are
monogamous and territorial. The pair excavates a burrow in an earth bank and lays two or more white eggs onto the bare surface. Both parents incubate the eggs and feed the chicks. Egg laying is staggered at one-day intervals so that if food is short only the older larger nestlings get fed. The chicks are naked, blind and helpless when they hatch, and stand on their heels, unlike any adult bird.
Feeding
The small
Ceyx and
Ispidina species feed mainly on insects and spiders, but also take tadpoles, frogs and
mayfly nymphs from puddles. The will flycatch, and their bills are red bills are flattened to assist in the capture of insects. The
Alcedo kingfishers are typically fish-eaters with black bills, but will also take aquatic invertebrates, spiders and lizards. A few species are mainly insectivorous and have red bills. Typically fish are caught by a dive into the water from a perch, although the kingfisher might hover briefly.
