email a friend
printable version
Milky Stork Mycteria cinerea
BirdLife is updating this factsheet for the 2016 Red List
Please email us with any relevant information
BirdLife Species Champion Become a BirdLife Preventing Extinctions Programme Supporter
For information about BirdLife Species Champions and Species Guardians visit the BirdLife Preventing Extinctions Programme.

This stork has been uplisted to Endangered because recent population estimates from its stronghold in Sumatra suggest that it is undergoing a very rapid ongoing population decline owing to intense hunting pressure at nesting colonies, human disturbance and the rapid loss and conversion of coastal habitat.

Taxonomic source(s)
del Hoyo, J.; Collar, N. J.; Christie, D. A.; Elliott, A.; Fishpool, L. D. C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Barcelona, Spain and Cambridge UK: Lynx Edicions and BirdLife International.

92-97 cm. White stork with thick, yellowish bill and blackish flight feathers. Juvenile has paler brown, more streaked head and neck, and darker wing-coverts contrasting sharply with upperparts. Similar spp. Painted Stork M. leucocephalus has black markings on wing-coverts and breast, pink on inner wing-coverts and tertials and more restricted naked head skin.

Distribution and population
Mycteria cinerea occurs in Cambodia, Peninsular Malaysia and the islands of Sumatra, Java, Bali, Sumbawa, Sulawesi and Buton, Indonesia (BirdLife International 2001). The vast majority are in Indonesia, with perhaps 1,600 birds on Sumatra in 2008-2009 (down from estimates of c.5,000 in the late 1980s) and <500 in west Java (Iqbal et al. in prep.) There are records from elsewhere in Indonesia, including Sulawesi, Bali, Lombok and Sumbawa (Birdlife International 2001), but little recent information and no known breeding colonies. There are estimated to be c.10-20 pairs at Tonle Sap lake, Cambodia (J. Eames in litt. 2006), with 17 pairs in 2010 (van Zalinge et al. 2011). It is a vagrant to Thailand and Vietnam. Numbers have apparently declined in most parts of its range, with counts from Malaysia falling consistently from over 100 individuals in 1984, to fewer than 10 birds in 2005 (Malaysian Nature Society 2005, Li et al. 2006), and only a single wild bird was recorded in the Matang Mangrove Forest in 2010 (DWNP 2010). On Sumatra, although good numbers can still be found at some sites in South Sumatra province it has apparently declined considerably (Li et al. 2006, M. Iqbal in litt. 2006, Iqbal and Hasudungan 2008, Iqbal et al. in prep.). The largest counts in recent years have included 500 birds in 2005 in Muara Padang subdistrict, South Sumatra (Iqbal & Hasudungan 2008), a breeding colony estimated to contain 100-115 nests at Kumpai lake (South Sumatra) in 2008 (Iqbal et al. 2008), and a maximum count of 278 birds at Bagan Percut (North Sumatra province) in 2005 (Shepherd & Giyanto 2009).

Population justification
The global population was previously thought likely to total fewer than 5,000 individuals, roughly equating to 3,300 mature individuals, based on estimates of c.5,000 individuals in Sumatra in the late 1980s (Silvius and Verheugt 1989) and 100-150 individuals in Java (M. Silvius in litt. 2002), plus 10 birds in Malaysia and 20-40 in Cambodia. Recent estimates put the global population far lower, at around 2,200 birds, based on totals of c.1,600 in Sumatra (c.75 individuals in Aceh province, c.500 North Sumatra province, c.350 Riau province, c.100 Jambi province, c.500 South Sumatra province and c.75 Lampung province), c.500 individuals, but possibly fewer, on Java, and <100 birds on the mainland of South-East Asia (Iqbal et al. in prep). This roughly equates to 1,500 mature individuals.

Trend justification
This species's population is suspected to be declining very rapidly in line with intense hunting pressure at nesting colonies and the rapid loss and conversion of coastal habitat. Estimates for Sumatra, which holds the bulk of the global population, fell from 5,000 birds in 1986 (Silvius 1988, Silvius & Verheugt 1989), to 1,600 in 2009 (Iqbal et al. in prep). In Java, a wintering flock in east Madura of 170+ birds observed in 1996 had diminished to c.70 birds in 2006, which may be representative of an island-wide decline (B. van Balen in litt. 2013). Numbers in Malaysia fell from counts of over 100 individuals in 1984, to fewer than 10 birds in 2005, and only a single wild bird in 2010 (Malaysian Nature Society 2005, Li et al. 2006, DWNP 2010). The tiny Cambodian population may be relatively stable, but at the global scale very rapid ongoing declines of 50-79% in three generations (25 years) are estimated.

It is a predominantly coastal resident in Indonesia and Malaysia, inhabiting mangroves and adjacent, less saline, swamps. It forages on tidal mudflats, in saline pools, freshwater marshes, fishponds and rice-fields. The species has been documented as eating fishes, prawns and crabs (Iqbal et al. 2008, 2009). Birds only occur inland in flooded forest around Tonle Sap lake in Cambodia, from where they disperse in the wet season, possibly to the coast (van Zalinge et al. 2011).

In Indonesia, tidal forests including mangroves are threatened by agricultural conversion and development schemes, particularly large-scale fish farms and tidal rice cultivation, logging and related disturbance; as a result, mangrove clearance has been rapid. Hunting for food and trade also exerts a significant pressure throughout its range. In 1989, 40-50 birds were shipped to zoos across South-East Asia. Persecution and disturbance at nesting colonies are thought to be the main threat in Malaysia. The same is said to be the case in South Sumatra, where local people hunt the species and take chicks and eggs for food and domestication (Iqbal et al. 2008), and harvesting of chicks was still taking place in 2008-2009 (Iqbal et al. in prep). In Cambodia, exploitation of waterbird eggs and chicks and snaring of adults, for food and trade, coupled with the increasing likelihood of conversion of flooded forest for agriculture, threaten the Tonle Sap lake breeding colony, although the small population here is currently well-protected. Poisoning may be another significant, as yet unquantified, threat. Hybridisation with with Painted Stork M. leucocephala has occurred at Ang Trapeang Thmor Sarus Crane Reserve, Cambodia in 2007 and 2008, as well as in captive populations, including free-flying birds (Eames 2007, Yong D. L. in litt. 2011, J. C. Eames in litt. 2011). The potential spread of Milky and Painted Storks from an unringed and full-winged colony at the National Zoo in Kuala Lumpur is a potential threat to pure wild stock (D. Bakewell in litt. 2013). These Painted Storks have now reached the Selangor coast, and if they move northwards cross-breeding with the Milky Storks in Matang could be a possibility - hybrids have already been reported in the greater Klang Valley (Y. C. Aik in litt. 2012). Free-flying Painted and Milky Storks also occur at Singapore Zoo, and hybridisation has apparently produced reproductively viable offspring (Yong D. L. in litt. 2011), raising the possibility that these birds could cross to Sumatra and mix with key Milky Stork populations.

Conservation Actions Underway
CITES Appendix I. Colonies are located in at least five protected areas in Sumatra and one each in Java, Sulawesi and Peninsular Malaysia. At Tonle Sap lake, Cambodia, large waterbird breeding colonies are designated core areas of the Biosphere Reserve, are proposed as Ramsar Sites, and have received active monitoring and improved enforcement of regulations since 1997. In Cambodia, posters depicting the species are used in promoting public environmental awareness. The Milky Stork Breeding and Re-introduction Programme, run by a number of stakeholders, coordinates the captive breeding and release of individuals into the Kuala Selangor Nature Park, Malaysia (Malaysian Nature Society 2005). Efforts are underway to effect legislative protection of the Matang Mangrove Forest Reserves in Perak, Malaysia, and advocacy is being used as an additional tool in the species's conservation (Malaysian Nature Society 2005). Successful breeding in captivity, survival of free-flying released birds, and attempted nesting in the wild by captive-bred individuals has been achieved in Malaysia (Malaysian Nature Society 2005). A total of 31 birds were released between 2007-2010, and successful hatching of two chicks occurred in 2010 (DWNP 2010). Surveys of the population in Sumatra took place in 2008-2009 (Iqbal et al. in prep). Conservation Actions Proposed
Conduct surveys and research to locate additional colonies, monitor seasonal movements and clarify its ecological requirements. Monitor numbers and breeding success at all known important nesting colonies. Establish additional protected areas encompassing important nesting colonies and feeding areas, particularly in the Riau, Jambi and Sumatra Selatan provinces of Sumatra and Matang Mangrove Forest in Malaysia. Promote public-awareness initiatives highlighting its conservation importance.

BirdLife International. 2001. Threatened birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, U.K.

Delany, S.; Scott, D. 2006. Waterbird population estimates. Wetlands International, Wageningen, The Netherlands.

DWNP. 2010. Annual Report 2010. Department of Wildlife and National Parks Peninsular Malaysia, Kuala Lumpur.

Eames, J. C. 2007. Apparent hybridization of Milky and Painted Storks at Ang Trapaeng Thmor Sarus Crane Conservation Area, Cambodia. The Babbler: BirdLife in Indochina: 21.

Iqbal, M., Nurza, A., Giyanto, Mulyono, H. Nurrohman, E. in prep. . Recent status of Milky Stork Mycteria cinerea in Sumatra.

Iqbal, M.; Hasudungan, F. 2008. Observations of Milky Stork Mycteria cinerea during 2001-2007 in South Sumatra province, Indonesia. BirdingASIA 9: 97-99.

Iqbal, M.; Ridwan, A.; Takari, F.; Mulyono, H. 2008. Rediscovery of a Milky Stork Mycteria cinerea breeding colony in South Sumatra province, Indonesia. BirdingASIA: 62-66.

Iqbal, M.; Takari, F.; Mulyono, H.; Rasam. 2009. A note on the breeding success of Milky Stork Mycteria cinerea in 2008, South Sumatra province, Indonesia and more on its diet. BirdingASIA 11: 73-74.

Li Zuo Wei, D.; Siti Hawa Yatim; Howes, J.; Ilias, R. 2006. Status Overview and Recommendations for the Conservation of Milky Stork Mycteria cinerea in Malaysia: Final report of the 2004/2006 Milky Stork field surveys in the Matang Mangrove Forest, Perak. Wetlands International.

Li, Z.W.D., Yeap, C. A.; Kumar, K. 2007. Surveys of coastal waterbirds and wetlands in Malaysia, 2004-2006. In: Li, Z. W. D.; Ounsted, R. (ed.), The status of coastal waterbirds and wetlands in Southeast Asia: results of waterbird surveys in Malaysia (2004-2006) and Thailand and Myanmar (2006), pp. 1-40. Wetlands Internationa, Kuala Lumpur.

Malaysian Nature Society. 2005. Report on the Milky Stork captive breeding and re-introduction programme, Kuala Selangor Nature Park. Malaysian Nature Society, Kuala Lumpur.

Shepherd, C. R.; Giyanto. 2009. Observations of Milky Storks Mycteria cinerea in Percut, North Sumatra, Indonesia. BirdingASIA 11: 70-72.

Silvius, M. J.; Verheugt, W. J. M. 1989. The status of storks, ibises and spoonbills in Indonesia. Kukila: 119-132.

van Zalinge, R., Visal, S., Phreakdey, S. and Evans, T. 2011. The status and distribution of large waterbirds in the Tonle Sap Biosphere Reserve, 2010 update. Wildlife Conservation Society Cambodia Program, Phnom Penh.

Wetlands International. 2002. Waterbird population estimates. Wetlands International, Wageningen, Netherlands.

Further web sources of information
Detailed species accounts from the Threatened birds of Asia: the BirdLife International Red Data Book (BirdLife International 2001).

Explore HBW Alive for further information on this species

Search for photos and videos, and hear sounds of this species from the Internet Bird Collection

Text account compilers
Benstead, P., Bird, J., Davidson, P., Mahood, S., Peet, N., Pilgrim, J., Taylor, J., Tobias, J., Martin, R & Symes, A.

Brickle, N., Chamnan, H., Eames, J.C., Iqbal, M., Li, Z., Yong, D., Yeap, C., Evans, T., van Balen, B., Robson, C., Bakewell, D., Mahood, S. & Goes, F.

Recommended citation
BirdLife International (2016) Species factsheet: Mycteria cinerea. Downloaded from on 25/10/2016. Recommended citation for factsheets for more than one species: BirdLife International (2016) IUCN Red List for birds. Downloaded from on 25/10/2016.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Additional resources for this species

ARKive species - Milky stork (Mycteria cinerea) 0

Key facts
Current IUCN Red List category Endangered
Family Ciconiidae (Storks)
Species name author (Raffles, 1822)
Population size 1500 mature individuals
Population trend Decreasing
Distribution size (breeding/resident) 87,600 km2
Country endemic? No
Links to further information
- Additional Information on this species