Fr: Tantale ibis
Ang: Yellow-billed Stork
All: Nimmersatt
Esp: Tántalo Africano
Ita: Tantalo africano
Nd: Afrikaanse Nimmerzat
Sd: Afrikansk ibisstork
Photographers:
Callie de Wet
GALLERY
Jean Michel Fenerole
Photos d’Oiseaux du monde
Steve Garvie
RAINBIRDER Photo galleries & Flickr Rainbirder
Ken Havard
My Bird Gallery & Flickr gallery 1 & Flickr gallery 2
Tom Merigan
Tom Merigan’s Photo Galleries
Ingo Waschkies
My bird pictures on Pbase
Text by 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
ROBERTS BIRDS OF SOUTH AFRICA by G. R. Mc Lachlan and R. Liversidge – The Trustees of the John Voelcker Bird Book Fund – ISBN: 0620031182
BIRDS OF EAST AFRICA vol 1 by C.A.W. Guggisberg – Mount Kenya Sundries Ltd. – ISBN: 9966889051
Biodiversity Explorer – The Web of Life in Southern Africa
Wikipedia, the free encyclopaedia
Birds of Southern Africa (Tony Roocroft)
Welcome to WhoZoo (Jill Foley)
Yellow-billed Stork – Mycteria ibis
Ciconiiformes Order – Ciconidae Family
INTRODUCTION:
The Yellow-billed Stork is part of the tribe Mycteriini that includes the genera Mycteria and Anastomus. It was formerly placed in the genus Ibis, and it superficially resembles this family, but it differs by behaviour and structural features typical of the Ciconiidae.
This species has unusual and specialized bill and feeding techniques, using the tactile feeding behaviour. It often occurs in small groups on shores and sandy banks of shallow lakes and rivers. They are colonial breeders.
This species is found in sub-Saharan Africa where it is mostly resident.
DESCRIPTION OF THE BIRD:
Biometrics:
Length: 95-105 cm
Wingspan: 150-165 cm
Weight: M: 2300 g – F: 1900 g
The Yellow-billed Stork is a large stork with pinkish grey-white plumage and black flight-feathers and tail. The long neck is greyish-white.
In breeding plumage, it has naked red facial skin, extending beyond the eyes. Wing-coverts and back are tinged pink.
The long, bright yellow bill is thick at the base and slightly curved at tip. The eyes are dark brown. Long legs and feet are pink.
Male and female have similar plumage, but the male is slightly larger.
The juvenile is mostly dark brown with white underparts. The bare parts are much duller and the eyes are pale grey.
The immature is duller than adults with paler eyes too.
RANGE:
The Yellow-billed Stork is found in Africa S of Sahara, and in WC Madagascar. It is vagrant in Morocco, Tunisia and Egypt.
HABITAT:
The Yellow-billed Stork frequents a variety of wetland habitats including lakes, rivers, swamps, estuaries, lagoons, marine mudflats and ricefields. This species is less common in forested areas, although it may occur in savanna woodland.
It nests sometimes in towns, and some colonies can be associated with human habitations.
It forages in shallow water, usually between 10 and 40 centimetres deep, and avoids flooded areas and deeper expansive waterbodies, often unsuitable for its peculiar feeding behaviour.
CALLS AND SONGS: SOUNDS BY XENO-CANTO
The Yellow-billed Stork is usually silent except during the breeding season. It produces a long, loud, nasal sound like a squeaky hinge, and hisses, low grunts and whining calls around the nest. Bill-clapping accompanies the displays at nest.
BEHAVIOUR IN THE WILD:
The Yellow-billed Stork feeds on small freshwater fish usually swallowed whole. It also takes aquatic insects, crabs, worms, crustaceans, frogs, and occasionally small mammals and birds.
It forages by wading or walking through shallow water, probing with its long, partially open bill. It uses its sense of touch to locate and catch the preys. As soon as the bill touches a prey, a rapid snap-bill reflex occurs and the bird shuts the mandibles and raises the head to swallow the prey whole.
The Yellow-billed Stork also uses the typical foot-stirring technique to disturb the preys hidden in the sand and the vegetation of the bottom. It also takes advantage of preys displaced by large mammals such as Hippopotamus amphibius and crocodiles moving through the water.
When not feeding, it rests on protected sandbanks with herons, spoonbills and other large wading birds.
The Yellow-billed Stork is highly gregarious, including during the breeding season, and they usually form colonies in trees. This species has a wide repertoire of courtship displays common to all Mycteria storks. The male selects potential nest-sites and the female attempts to approach. Several displays typical of this genus include “Display preening” during which the male feigns to preen each of its extended wings with the bill, several times on each side, but actually, the bill does not touch the feathers.
Another display shows the male standing on the nest-site, bending over to grasp and release twigs from the foundations at regular intervals, while moving head and neck side-to-side between each action.
The female also performs displays such as the “Balancing Posture”. She walks with the body held horizontally, while extending the wings towards the male. She may engage in “Gaping” once near the male, with slightly open bill while the neck is held upwards.
If the female is accepted by the male, she enters the nest-site while closing her wings, whereas the male may continue its “Display Preening”. Both birds stand together in the nest. The copulation is accompanied by bill-clapping from the male.
A new pair is formed every year. The nest is not reused because it is often destroyed by other birds stealing materials for their own nests.
The Yellow-billed Stork is largely resident in the range, and only performs some local movements related to the seasons. It is probably an intra-Africa migrant.
It flies with projecting neck and feet, and like most Ciconidae, it uses its long, broad wings for soaring, because it is not able to sustain flapping flight. The flying groups do not fly in any regular formation.
REPRODUCTION OF THIS SPECIES:
The Yellow-billed Stork starts to breed towards the end of the rainy season, but it also nests during the dry season in drier regions, if the food resources are abundant.
It nests in mixed-species colonies established in trees with herons and other aquatic species. The colonies usually include 10-20 pairs, occasionally more, up to 50 pairs with nest 1-3 metres apart.
Both adults build a smallish nest, high up in trees such as Acacia, Bombax or Baobabs, sometimes over water.
The female lays 2-4 eggs (usually 3). Both adults incubate during about 30 days. At hatching, the chicks have white down. They are fed by their parents by regurgitation of fish. They also regurgitate water into the open bills of the chicks.
They fledge 50-55 days after hatching and leave the nest, but they return there to be fed and they roost with their parents during 1-3 weeks more. They are sexually mature at 3 years old.
PROTECTION / THREATS / STATUS:
The Yellow-billed Stork has wide range in which it is common to abundant, but only locally common in WC Madagascar.
The global population has not been quantified, but it is declining overall, although it can be locally stable. Despite its tolerance to natural habitat changes, the species is at risk from poaching and habitat reduction in East Africa.
However, the global population is not currently threatened and the Yellow-billed Stork is evaluated as Least Concern.
