Hadada Ibis

CLASSIFICATION

Class: Aves
Order: Ciconiiformes
Family: Threskiornothidae
Genus: Bostrychia
Species: hagedash

SIZE

Length: Male: 65-76 cm.
Female: 65-76 cm.

Weight: Male: 1260 grams
Female: 1260 grams

Wingspan: Male: 330-383 mm
Female: 330-383 mm

APPEARANCE:

Overall appearance is drab dark olive brown or greyish- brown, although there is a prominent green irridescence on the wing coverts. Eyes offset by a whitish stripe underneath it. Flight feathers and tail display an irridescent bluish-black. Bill is long, black and curved, with red at the base extending about halfway along the upper mandible. Legs are blackish-brown, feet a pale orange brown. No color difference between the sexes, but the female may be slightly smaller with a shorter bill.

The immature bird is similar to the adult but is somewhat duller, with a shorter bill. The nestling is blackish, almost naked.

In flight, the bill projects downward, and the legs and feet do not project beyond the tail.

RANGE/DISTRIBUTION:

General distribution is Gambia, Kenya Colony, Italian Somaliland, eastern and south-eastern Belgian Congo, Northern Rhodesia and the Zambesi River. In many parts of tropical and southern Africa, it is the most common ibis. It ranges from Senegal to eastern Zaire, and from the Sudan to the eastern Cape, not being found around the lower Congo River, nor in the dry southwestern areas.

HABITAT/TERRITORY SIZE:

It is the least aquatic of all the African ibises. Common habitats are open grasslands and savanna especially along wooded streams, marshes and river courses. Also common in pasturelands and cultivated land, but also found in timbered areas and occasionally found in the glades of deep forests. They are quite commonly seen around small towns and villages.

MIGRATION:

Mostly sedentary, but some local movement to wetter areas during droughts. Flocks of 5-30 birds and occasionally up to 200 have been known to wander several kilometers from the roost.

DIET:

Hadada Ibis are not dependent on watery areas for food and often feed well away from wet places, seemingly content to probe lawns and grasslands with its long curved bill as it searches for insects, worms and snails. They are very beneficial to agriculture.

HUNTING METHOD:

They are mostly tactile foragers, but occasionally will use their sight to help in feeding. Like most ibises, they specialize in “probing” the long bill into the mud in shallow water. They have different methods of catching the prey. The “bill snap” involves the rapid closing of the bill as a reflex reaction to the tactile stimulation generated by contact with prey. When prey is dead or scarcely moves, they will seize it by means of a “bill grab” using the bill as tweezers. Small prey items are normally swallowed immediately after capture, either by tossing the prey up in the air and catching it or by releasing it and moving the mouth forward to engulf it. Large, heavy or dangerous items of prey, which cannot be swallowed immediately, are manipulated using various methods, and may be battered, shaken, kneaded or ripped apart. After consuming a large prey item, ibis usually drink water.

BREEDING INFORMATION:

They have a lengthy breeding season, usually peaking during and after the main rain in some areas. The nest is a platform of twigs, sticks and branches lined with dry grass, usually built in trees at heights below 9 meters and close to or over water or a wooded stream. Sometimes nest in trees on cliff faces or use the old nests of other birds. Usually lay two to three eggs that are greyish green or buff with pale olive brown or chestnut spots and blotches. They are laid irregularly and may be in various stages of incubation. Incubation is 25-28 days and is done by both sexes. Chicks have rufous brown down and are independent at 49 days.

BEHAVIOR:

The bird’s name is derived from its rauccous call of “ha-ha-a-a-a-a”, usually uttered on the wing. At dawn, its rattling croaks are well known. Hadadas typically call around dusk or sunrise, when they are returning to the roost or leaving it. One bird starts calling, followed immediately by others. In large roosts, several groups may call simultaneously.

They roost in large companies with much noise and clamour. When disturbed Hadada Ibis often go to a neighboring tree. More solitary than most of the ibis species, they are normally gregarious at the roost, but will tend to nest alone. In Eastern Africa it is a common riverside ibis usually seen in pairs or small flocks on wooded watercourses with their alarming call being the first evidence of their presence. They have been known to become quite tame. When flying in flocks, Hadada Ibis do not fly in formation as other types of ibis will.

STATUS:

Not globally threatened. Common throughout its range, though more so in eastern and southern Africa than in western Africa. CITES III in Ghana

In the early 1900’s, Hadada Ibis underwent a marked decline in South Africa apparently due to hunting during a period of colonial expansion. Since 1910, it has been expanding toward western Africa, probably as a result of reduced human persecution following legal protection; proliferation of imported tree species, providing new sites for resting and nesting in formerly treeless areas; construction of reservoirs; increase in irrigated land; and arrival of cattle in zones recently colonized by mans, as cow dung favors expansion of coprophagous insects which is a frequent prey of the species.