Iora
| Ioras | |
|---|---|
 | |
| Marshall's Iora | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Passeriformes |
| Suborder: | Passeri |
| Family: | Aegithinidae G. R. Gray, 1869 |
| Genus: | Aegithina Vieillot, 1816 |
| Species | |
See text.
| |
The ioras are a family, Aegithinidae, of small passerine bird
species found in India and southeastAsia. The family has only four species in a single genus, Aegithina. They are one of only three bird families that are entirely endemic to the Indomalayan ecozone. They were formerly grouped with the other two of those families, the leafbirds and fairy-bluebirds, in the family Irenidae.
species found in India and southeastAsia. The family has only four species in a single genus, Aegithina. They are one of only three bird families that are entirely endemic to the Indomalayan ecozone. They were formerly grouped with the other two of those families, the leafbirds and fairy-bluebirds, in the family Irenidae.
Description
The ioras are small to medium small sized passerines, ranging from 11.5–15.5 cm (4.5–6.1 in) in length. Overall the males are larger than the females. These are reminiscent of the bulbuls, but whereas that group tends to be drab in colouration, the ioras are more brightly coloured. The group exhibits sexual dimorphism in its plumage, with the males being brightly plumaged in yellows and greens. Unlike the leafbirds, ioras have thin legs, and their bills are proportionately longer. Calls are strident whistles; songs are musical to human ears.
Habitat and movements
Their habitats include acacia scrub, forest edge, and closed forests, as well as agricultural land and (in the Common Iora) gardens. They are generally lowland birds, with most reaching only as high as the submontane forests. They are generally highly arboreal and usually occur in the tree canopy, with only very rare records of this family coming down to the ground. The family is overwhelmingly non-migratory, although in West India there is some evidence that Marshall's Ioras and Common Ioras are partly migratory in the seasonal semi-desert fringe.
Behaviour
Ioras eat insects and spiders, which they find by nimbly gleaning the leaves of the slenderest outer twigs.
In the two species whose male courtship displays are known, they are elaborate, culminating in the males' parachute-style descent looking like "green balls of fluff". The nests are compact open cups felted to branches with spiderweb. Females lay 2 or 3 eggs, which have pinkish speckles and red and purple lines. They incubate at night; the males, by day. Incubation lasts about 14 days. Both parents are responsible for brooding and feeding the chicks.
Relationship with humans
Ioras will commonly live close to humans and even lives in the suburbs of cites like Singapore. They are mostly not threatened by human activities, although the Green Iora is listed as near threatened by the IUCN, habitat loss is responsible for its decline. Unlike many other passerines they are not common species in the cage bird trade.
Species of Aegithinidae
- Common Iora, Aegithina tiphia
- Marshall's Iora, Aegithina nigrolutea
- Green Iora, Aegithina viridissima
- Great Iora, Aegithina lafresnayei
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