[order] ACCIPITRIFORMES | [family] Accipitridae | [latin] Aviceda jerdoni | [authority] Blyth, 1842 | [UK] Jerdons Baza | [FR] Baza de Jerdon | [DE] Hinduweih | [ES] Baza oriental | [NL] Jerdons Koekoekswouw
Monotypic species
Genus
Members of the genus Aviceda are rather small to medium-sized kites (usually called Cuckoo-Falcons or Bazas). Their wings quite long and pointed, the tail is of moderate length and not forked. The edge of the upper mandible has two clearly indicated tooth-like protrusions. They have short, stout legs and feet with well developed talons. Two or three feathers of the nape are elongated as a crest, which is very pronounced in the Black Baza (Aviceda leuphotes) but barely noticeable in the Madagascar Cuckoo-falcon (Aviceda madagascariensis). Adults of the genus are often boldly patterned and barred; the young less so.
The adult male of the nominate race (Aviceda jerdoni jerdoni) found in northern India and southern continental Asia is dark brown or black around the crown and nape, with a small number of long black, white-tipped feathers on the nape forming a noticeable crest. The feathers of the upper back are rufous, those of the lower back, scapulars and wing coverts are dark brown, some with paler edges. The tail is greyish brown, with a buff tip, a broad dark brown band near the tip, and two to four narrower bands. The primaries and secondaries are dark brown, with black bars, the innermost secondaries and coverts are more rufous, with white tips. The inner webs are white below the notch, contrasting strongly with the black bars. Below the chin and throat is white with a median black streak. The underside is mostly white, barred with chestnut. The eyes are yellow, the cere pale blue-grey, and the legs yellow. The immature differs from the adults in being paler above, with more buff edgings to the feathers, and in having the upper breast white, heavily streaked with black. The under-wing is also whiter.
Aviceda jerdoni ceylonensis of Sri Lanka and southern India is smaller, paler above and below with the bars on the underside less distinct. Aviceda jerdoni borneensis of Borneo is also smaller, more richly coloured, darker above, with the sides of the face and neck being rufous, and is more heavily barred chestnut below. Aviceda jerdoni magnirostris of the Philippines is smaller, too. It has a stouter bill and a plain black crest. The sides of its face and throat are grey, and the rufous banding below is darker than that of the nominate race, but paler than is found in the Bornean race. Aviceda jerdoni celebensis inhabits the Celebes, Banggai, and Sula Islands. It, too, is smaller. It is darker above, the crown and nape are rich rufous streaked with black, and it has much heavier and richer chestnut barring below.
Listen to the sound of Jerdons Baza
[audio:http://www.planetofbirds.com/MASTER/ACCIPITRIFORMES/Accipitridae/sounds/Jerdons Baza.mp3]
Copyright remark: Most sounds derived from xeno-canto
| wingspan min.: |
112 |
cm |
wingspan max.: |
122 |
cm |
| size min.: |
41 |
cm |
size max.: |
48 |
cm |
| incubation min.: |
0 |
days |
incubation max.: |
0 |
days |
| fledging min.: |
0 |
days |
fledging max.: |
0 |
days |
| broods: |
1 |
|
eggs min.: |
2 |
|
| |
|
|
eggs max.: |
3 |
|
Oriental Region : widespread. The breeding range of the Jerdon’s Baza is from Sikkim east through Assam and Laos to Hainan and the Philippines, South to Celebes, Borneo, Sumatra and Sri Lanka. There are a number of local distributions in south-western and north-eastern India
It favours forests, or clearings on the edge of forests, and is often found in tea gardens. It lives in the altitude range 150-750 metres, and it is seldom observed, although not particularly rare. It is sluggish, perching for a lot of its time at forest edges. In flight it flaps strongly, with short glides. It is mostly crepuscular, and is more likely to be seen in the open in the late evening. Where it occurs it is often seen in pairs. It sometimes leaves the forest during the breeding season and soars at some height. It is not an aggressive bird, and does not attack any large or powerful prey. It is, in fact, slow on the wing and would have much difficulty catching birds.
Early in the breeding season the pair soar above the forest together, and are seen much in each other’s company. One, or possibly both birds perform diving aerobatic displays, stooping and climbing, turning over at the top of the upward swoop and plunging down again. The display is accompanied by loud calling. Mating takes place on trees, with display calls. The birds build a new nest each season. It is made of twigs, carried mainly in the birds’ feet, and placed in a tree. It is a small, compact structure lined with green leaves, generally low down even in the biggest of trees. Very often it is near a stream, although this may be a coincidence in some areas where forest is confined to the vicinity of streams. Two or three greenish white eggs are laid, often stained, but with no true markings. In southern India and Ceylon the eggs are laid from February to early April, possibly even earlier, and also in September; in northern India in April. The breeding season is fairly elastic, as would suit a largely insectivorous bird, and it commences during the monsoon rains and extends into the following dry season. The whole breeding season in Sri Lanka, from display to completion, lasts from November to May. Juveniles accompany the parents after fledging for some time, and parties of adults and immatures may be seen together.
The Jerdon’s Baza lives on a diet composed mostly of insects, taken in trees and on the ground. Is also eats lizards and frogs, and these are also taken on the ground.
httpv://www.youtube.com/watch?v=UxPKJnCy78c
copyright: youtube
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be small, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Sedentary; recorded throughout year in virtually all of range. Some birds, possibly juveniles, from North of range apparently disperse or migrate South into Thailand, where movements recorded, and into Malay Peninsula, where only records are in winter.
