Data Zone
Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
| Critically Endangered | Endangered | Vulnerable |
|---|---|---|
| - | - | A2cd+3cd+4cd |
| Year | Category | Criteria |
|---|---|---|
| 2016 | Vulnerable | A2cd+3cd+4cd |
| 2013 | Vulnerable | A2cd+3cd+4cd |
| 2012 | Vulnerable | A2cd+3cd+4cd |
| 2008 | Vulnerable | A2c,d; A3c,d; A4c,d |
| 2006 | Vulnerable | |
| 2004 | Vulnerable | |
| 2000 | Vulnerable | |
| 1996 | Vulnerable | |
| 1994 | Vulnerable | |
| 1988 | Threatened |
| Migratory status | full migrant | Forest dependency | medium |
| Land mass type |
land-mass type - continent land-mass type - shelf island |
Average mass | 4651 g |
| Estimate | Data quality | |
|---|---|---|
| Extent of Occurrence breeding/resident (km2) | 11,300,000 | medium |
| Extent of Occurrence non-breeding (km2) | 13,100,000 | medium |
| Number of locations | 11-100 | - |
| Severely Fragmented | - |
| Value | Data quality | Derivation | Year of estimate | |
|---|---|---|---|---|
| No. of mature individuals | 5500-10000 | poor | estimated | 2013 |
| Population trend | decreasing | poor | suspected | - |
| Decline (3 years/1 generation past) | - | - | - | |
| Decline (5 years/1 generation past) | - | - | - | |
| Decline (10 years/1 generation past) | - | - | - | |
| Decline (10 years/3 generation future) | 30-49 | - | - | - |
| Decline (10 years/3 generation past and future) | 30-49 | - | - | - |
| Number of subpopulations | 2-100 | - | - | - |
| Percentage in largest subpopulation | 1-89 | - | - | - |
| Generation length (yrs) | 16.1 | - | - | - |
Population justification: A total population of 5,000 individuals was previously estimated by Hancock (1993), Choudhury (2000) and BirdLife International (2001). However, more extensive survey effort in recent years has led to upward revisions of some national totals: in particular the Cambodian population is now thought to number perhaps 1,500-3,500 pairs or 3,000-7,000 mature individuals (Goes 2013, S. Mahood in litt. 2013). Taking this total and perhaps 1,200 mature individuals in India, c.300 in Malaysia, 200-700 in Nepal, 250-400 individuals in Myanmar (Zöckler et al 2014; in litt) plus an unknown number in Indonesia (previously estimated at 2,000 individuals in 1993 but may have severely declined since), and assuming only very small numbers elsewhere, the global population probably numbers 5,500-10,000 mature individuals (roughly equating to 8,000-15,000 individuals).
Trend justification: This species's population is suspected to be declining rapidly, in line with increasing levels of felling of colony nest trees, drainage and conversion of wetland feeding areas, agricultural intensification, pesticide use, disturbance and large-scale development in coastal areas, but, most seriously, the persistent and unregulated harvesting of eggs and chicks from colonies.
Successes in parts of Cambodia are likely to be isolated and may be short-term (C. Robson in litt. 2013), and declines are predicted to be ongoing elsewhere in the country . In Indonesia, estimates in South Sumatra and Jambi provinces in 1984-1986 were 514 birds (388-620) and 272 (152-475) birds respectively, while surveys in these provinces in 2001-2004 estimated only 124 birds (30-318) and 7 birds (2-17) respectively (M. Iqbal in litt. 2013), suggesting that very rapid declines may have occurred on Sumatra.
| Country/Territory | Presence | Origin | Resident | Breeding | Non-breeding | Passage |
|---|---|---|---|---|---|---|
| Bangladesh | extant | native | yes | |||
| Bhutan | extant | vagrant | ||||
| Brunei | extant | native | yes | |||
| Cambodia | extant | native | yes | |||
| China (mainland) | possibly extinct | native | yes | |||
| India | extant | native | yes | |||
| Indonesia | extant | native | yes | |||
| Laos | extant | native | yes | |||
| Malaysia | extant | native | yes | |||
| Myanmar | extant | native | yes | |||
| Nepal | extant | native | yes | |||
| Singapore | extinct | native | yes | |||
| Sri Lanka | extant | native | yes | |||
| Thailand | extant | native | yes | |||
| Vietnam | extant | native | yes |
| Habitat (level 1) | Habitat (level 2) | Importance | Occurrence |
|---|---|---|---|
| Artificial/Aquatic & Marine | Artificial/Aquatic - Water Storage Areas (over 8ha) | suitable | resident |
| Artificial/Terrestrial | Arable Land | suitable | resident |
| Forest | Subtropical/Tropical Dry | suitable | resident |
| Forest | Subtropical/Tropical Moist Lowland | major | resident |
| Marine Coastal/Supratidal | Coastal Brackish/Saline Lagoons/Marine Lakes | major | resident |
| Marine Intertidal | Mangrove Submerged Roots | major | resident |
| Marine Intertidal | Mud Flats and Salt Flats | major | resident |
| Marine Intertidal | Salt Marshes (Emergent Grasses) | major | resident |
| Savanna | Dry | suitable | resident |
| Wetlands (inland) | Permanent Freshwater Lakes (over 8ha) | major | resident |
| Wetlands (inland) | Permanent Freshwater Marshes/Pools (under 8ha) | major | resident |
| Wetlands (inland) | Permanent Rivers/Streams/Creeks (includes waterfalls) | major | resident |
| Altitude | Occasional altitudinal limits |
| Threat (level 1) | Threat (level 2) | Impact and Stresses | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Agriculture & aquaculture | Annual & perennial non-timber crops - Agro-industry farming | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
| Agriculture & aquaculture | Marine & freshwater aquaculture - Scale Unknown/Unrecorded | Timing | Scope | Severity | Impact | ||||
| Ongoing | Minority (<50%) | Slow, Significant Declines | Low Impact: 5 | ||||||
|
|||||||||
| Biological resource use | Fishing & harvesting aquatic resources - Unintentional effects: (subsistence/small scale) [harvest] | Timing | Scope | Severity | Impact | ||||
| Ongoing | Minority (<50%) | Slow, Significant Declines | Low Impact: 5 | ||||||
|
|||||||||
| Biological resource use | Hunting & trapping terrestrial animals - Intentional use (species is the target) | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
| Biological resource use | Logging & wood harvesting - Unintentional effects: (large scale) [harvest] | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
| Biological resource use | Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] | Timing | Scope | Severity | Impact | ||||
| Ongoing | Minority (<50%) | Slow, Significant Declines | Low Impact: 5 | ||||||
|
|||||||||
| Energy production & mining | Mining & quarrying | Timing | Scope | Severity | Impact | ||||
| Ongoing | Minority (<50%) | Slow, Significant Declines | Low Impact: 5 | ||||||
|
|||||||||
| Human intrusions & disturbance | Work & other activities | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
| Pollution | Agricultural & forestry effluents - Type Unknown/Unrecorded | Timing | Scope | Severity | Impact | ||||
| Ongoing | Minority (<50%) | Slow, Significant Declines | Low Impact: 5 | ||||||
|
|||||||||
| Purpose | Primary form used | Life stage used | Source | Scale | Level | Timing |
|---|---|---|---|---|---|---|
| Food - human | - | - | non-trivial | recent | ||
| Pets/display animals, horticulture | - | - | international | non-trivial | recent |
Recommended citation
BirdLife International (2023) Species factsheet: Leptoptilos javanicus. Downloaded from
http://datazone.birdlife.org/species/factsheet/lesser-adjutant-leptoptilos-javanicus on 02/06/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from
http://datazone.birdlife.org on 02/06/2023.
