Storm’s stork  (Ciconia stormi)

Classified as Endangered (EN) on the IUCN Red List 2007 (1).

Storm’s stork is a large black and white bird with a slightly upturned, red bill (3), orange facial skin and golden-yellow area around eye (2). The wings, back, crown and breast are black, while the throat, nape of the neck, abdomen and vent are white (3).

Known from extreme southern Thailand, where it is now almost certainly extinct, through Peninsular Malaysia to the islands of Borneo and Sumatra, Indonesia (4). Overall, the population is now estimated to number just 250 to 500 individuals (2).

Found in lowland undisturbed freshwater habitats, particularly peat swamp forests, on the floodplains of large rivers (2) (5). Disturbed, recently burned and logged areas are also frequented, and occasionally areas subject to tidal movements (2).

Storm’s stork is generally solitary, but is occasionally found in small groups (2). This species is thought to feed primarily on fish, but also on frogs, crustaceans, earthworms, invertebrates and aquatic insect larvae (4) (5).

Little is known about the reproductive biology of this species (5). Some form of aerial display occurs during courtship in which pairs do flips in flight, with the lower bird presenting its feet to the upper, or both birds gliding at high altitudes with level wings and legs dangling. Such displays have been observed in March in Sabah (Malaysia) on Borneo (4). Very few nests have been found, but it appears that storm’s stork is a solitary tree-nester (4) (5). In Thailand, chicks have been recorded to hatch in late October (4) (5). Clutches are thought to contain two or more eggs (5), and the chicks are able to fly after around 90 days (2).

Storm’s stork has a very small, fragmented population that is rapidly declining due to destruction of its lowland forest habitat through logging, dam construction and conversion to oil-palm plantations. The major fires of 1997-1998 on Sumatra and Borneo are thought to have had a significant impact on this bird, and the development of lowland rivers as major transport routes is considered a considerable threat. Fortunately, incidental hunting and trade are minor threats to this species (2).

Storm’s stork is legally protected in Thailand, Malaysia and Indonesia and has been recorded in several protected areas, including at least five (and one proposed) in Kalimantan, at least four (and a further four proposed) on Sumatra and four in Malaysia (2).

View information on this species at the UNEP World Conservation Monitoring Centre.

For more information on Storm’s stork see:

• BirdLife International. (2001) Threatened Birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, UK.
• del Hoyo, J., Elliott, A. and Sargatal, J. (1992) Handbook of the Birds of the World – Ostrich to Ducks. Vol. 1. Lynx Edicions, Barcelona.