Hadada Ibis
SCIENTIFIC NAME
Bostrychia hagedash (Also found as Hagedashia hagedash)
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.
FOLKLORE AND MYTHS:
The ancient
Egyptians acknowledged the Nile as the source and protector of life,
so any ibis which appeared in the region during the annual flooding
of the great river was considered worthy of their adoration.
BIBLIOGRAPHY:
Unknown
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