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PROTECTION / THREATS / STATUS:
The African Openbill may be common in suitable habitat, but the species is threatened by habitat loss, disturbances on feeding areas and pollution by pesticides used to eradicate mosquitoes.
This bird suffers from hunting and poaching, but also trading at traditional medicine markets in Nigeria.
The race “madagascariensis” is rather common in WC Madagascar, but declines occurred in recent years, due to destruction of colonies by villagers.

Fr: Bec-ouvert Africain
All : Mohrenklaffschnabel
Esp : Picotenaza Africano
Ital: Anastomo africano
Nd: Afrikaanse Gaper

Photographers:

Steve Garvie
RAINBIRDER Photo galleries

David Nowell
Virtually Home - Photo Gallery

Callie de Wet
Flickr Galleries

Texte de Nicole Bouglouan

Sources:

HANDBOOK OF THE BIRDS OF THE WORLD vol 1 by Josep del Hoyo-Andrew Elliot-Jordi Sargatal - Lynx Edicions - ISBN: 8487334105

BIRDS OF AFRICA SOUTH OF THE SAHARA by Ian Sinclair and Peter Ryan - Princeton University Press Princeton and Oxford - ISBN: 0691118159

BIRDS OF THE GAMBIA AND SENEGAL by Clive Barlow and Tim Wacher – Helm Field guides – ISBN: 0713675497

L’ENCYCLOPEDIE MONDIALE DES OISEAUX - Dr Christopher M. Perrins -  BORDAS - ISBN: 2040185607

Avibase (Lepage Denis)

BirdLife International (BirdLife International)

Biodiversity Explorer – The Web of Life in Southern Africa

 

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Page Family Ciconidae

Summary cards

African Openbill
Anastomus lamelligerus

Ciconiiforme Order – Ciconiidae family

BIOMETRICS:
Length: 80-94 cm
Weight: 1000-1300 g

DESCRIPTION:
Like the other member of the genus Anastomus, the Asian Openbill, the African Openbill has an unusual bill well adapted to the feeding behaviour of both species. These birds feed mainly on large aquatic snails of the genus Pila, and this type of bill is useful to extract the mollusc from the shell.  

Both adults are similar, with male larger than female.
The plumage is black overall, with glossy green, brown or purple mantle and breast.
The large bill is brownish-horn, paler towards the base. The mandibles show a wide gap between them of about 5-6 mm, and join only at tip. On the almost straight upper mandible, there are several small columnar pads, about 20-30, which help the bird to grip the shell and then, to extract the mollusc.
Eyes are grey with bluish lores and bare eye-ring. Legs and feet are blackish.

Immature is duller and browner, with pale feather tips on the upperparts. The bill is almost straight, with narrower gap between the mandibles. The young develops the gap little by little with the maturity.

IMMATURE

We can find two subspecies:
A.l. lamelligerus is found in Africa, South of the Sahara.  
A.l. madagascariensis occurs in Madagascar. This race is smaller. The bill is thinner and shows more pronounced ridges.

VOICE: SOUNDS BY XENO-CANTO
The African Openbill produces bill-clatters during the displays, as most of Ciconiidae species do. It also gives loud croaks and honks.

HABITAT:
The African Openbill frequents mainly extensive freshwater wetlands, and it is often found in marshes, swamps, margins of lakes and rivers, ricefields and flooded plains. It may sometimes frequent moist savannahs and burnt grasslands, and occasionally streams with nearby tall trees for nesting.

RANGE:  
The African Openbill is found in Africa, South of the Sahara, but it is infrequent throughout West Africa.
It also occurs in Madagascar, mainly on the western regions.

This species performs some migrations, with regular transequatorial movements of birds arriving in West Africa for the dry period. They migrate in flocks, but these movements are not very well understood.   
The South African birds can be resident according to the weather conditions.

BEHAVIOUR:
The African Openbill feeds primarily on aquatic snails, but it also takes freshwater mussels. According to the range, and especially in Uganda, it takes terrestrial snails, but also frogs, crabs, fish, worms and large insects.

Its typical bill is adapted to its feeding behaviour. The bird detects the snail by sight and by touch, and catches it between the mandibles.

Then, it introduces the lower mandible’s tip into the shell, in order to remove the operculum and to cut the strong muscle, and finally, it extracts the molluscs while the shell is held with the upper mandible tip against the ground.

The African Openbill feeds singly or in small groups, walking slowly in shallow water, and digging into the mud with the bill. It may be seen on the back of grazing hippopotamus, waiting for snails disturbed by the huge animal.
It often returns to the same site to feed the snails, and little by little, shells accumulate and form a pile.

The African Openbill starts the breeding season just before, at the beginning or late in rains, involving the emergence of the snails. During the nesting period, these birds carry snails in bill tip to the nest to feed the young. Large colonies often have a shell litter just below.

The African Openbills are highly gregarious including during the breeding season. They perform the typical display of storks such as “up-down” or greeting display between mates, also used to strengthen the pair-bonds. It is accompanied by bill-clattering.

They also perform the “Advertising display” with the male rocking from one leg to the other and the head held down between the legs. This display occurs on a branch.

Copulation occurs frequently during the nest building, and usually on the nest itself, accompanied by bill-clattering by the male.

They nest in colonies of various sizes and usually over water.

FLIGHT:
The African Openbill performs sustained flapping flight during migrations. It also uses thermals in long-distance flights.
It flies with outstretched head and neck, and the broad, long wings are well adapted for soaring.

REPRODUCTION:
Breeding period occurs in rainy season, between August and May, with peak in January-March.
The African Openbill nests in colonies of varying numbers of pairs. They nest in trees, usually over water, and sometimes in reedbeds.
This medium-sized bird builds a relatively small nest of about 50 cm wide, a platform made with sticks and reeds, and lined with aquatic vegetation, sedges, grass and leaves.

Female lays 3-4 oval, chalky-white eggs. Incubation is shared by both sexes and lasts about 25-30 days.

At hatching, the downy chicks are black with normal bill. The gap will develop over several years.

They are fed by both parents, and fledge about 50-55 days after hatching.

DIET:
The African Openbill feeds mainly on aquatic apple snails of genus Pila, which are freshwater snails with hard operculum. This fact involves very well adapted bill to extract the mollusc from the shell after the cutting of the muscle. These snails are found in very muddy waters.
This species also takes freshwater mussels of genus Ampullaria, and frogs, crabs, worms, fish and large insects such as locusts and beetles.
It usually feeds in small groups by walking slowly in shallow muddy water.