Giant Ibis (Pseudibis gigantea)

Giant Ibis

[order] CICONIIFORMES | [family] Threskiornithidae | [latin] Pseudibis gigantea | [authority] Oustalet, 1877 | [UK] Giant Ibis | [FR] Ibis geant | [DE] Riesenibis | [ES] Ibis Gigante | [NL] Reuzenibis


Monotypic species


The bird genus Pseudibis consists of two South-East Asian species in the ibis subfamily, Threskiornithinae. The Giant Ibis is also sometimes placed in this genus, as it is on PoB. It is closely related to the genus Geronticus.

Physical charateristics

Huge, dark ibis. Adult is mostly dark with naked, greyish head and upper neck, dark bands on hindcrown and nape and pale greyish wing-coverts and secondaries with dark cross-bars. Juvenile has short black feathers on hindcrown and hindneck, shorter bill and brown eyes (dark red on adults).

Listen to the sound of Giant Ibis

[audio: Ibis.mp3]

Copyright remark: Most sounds derived from xeno-canto

wingspan min.: 0 cm wingspan max.: 0 cm
size min.: 100 cm size max.: 108 cm
incubation min.: 0 days incubation max.: 0 days
fledging min.: 0 days fledging max.: 0 days
broods: 1   eggs min.: 1  
      eggs max.: 3  


Oriental Region : South Vietnam. Thaumatibis gigantea is confined to northern Cambodia, where it is probably still fairly widespread but extremely rare; with a few birds surviving in extreme southern Laos, and a recent record from Yok Don National Park, Vietnam


Singles, pairs or small parties occur in marshes, pools, wide rivers and seasonal water-meadows in open, predominantly deciduous, dipterocarp lowland forest, although it seems to be dependent on soft mud around seasonal pools (trapaengs)


It nests in trees, with a preference for large Dipterocarpus, generally more than 4 km from human habitation. Females almost always lay two eggs per clutch. Pools and seasonally flooded grassland with earthworm mounds are important in the breeding season. No further data.

Feeding habits

Its diet comprises a variety of invertebrates, crustaceans, small amphibians and reptiles. It frequently feeds in soft mud, but also forages on dry substrates.

Video Giant Ibis


copyright: Josep del Hoyo


This ibis has an extremely small, declining population as a result of hunting, disturbance and lowland deforestation. It is likely to continue to decline owing to deforestation and human disturbance. It therefore qualifies as Critically Endangered.
It has declined as a result of hunting, wetland drainage for agriculture, and deforestation. It relies on seasonal pools, which in the past were created by the now much depleted megafauna. The species appears to be very sensitive to human disturbance, particularly during the dry season when birds are concentrated around available waterholes, and this is almost certainly the greatest threat, rendering much apparantly suitable habitat unusable. There are plans to clear large areas of lowland dry forest, including Western Siem Pang IBA where the species occurs, for teak plantations. In the Kulen Prumptep Wildlife Sanctuary the human population is increasing and subsequent expansion of agricultural land is causing loss of breeding habitat for the species. Nest predation by common palm civet Paradoxurus hermaphroditus and/or yellow-throated marten Martes flavigula on two occasions in 2004 suggest that loss of nestlings to mammalian carnivores might be a significant constraint on breeding success, a theory supported by a study which found the number of young fledged per nest was 50% higher for protected nests.
Giant Ibis status Critically Endangered


Probably sedentay but migrants and/or vagrants have been reported.

Distribution map

Giant Ibis distribution range map

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