Pseudibis davisoni

Taxonomy

Assessment Information

Geographic Range

Population

Habitat and Ecology

Threats

Conservation Actions

View Printer Friendly

Taxonomy [top]

Kingdom	Phylum	Class	Order	Family
ANIMALIA	CHORDATA	AVES	CICONIIFORMES	THRESKIORNITHIDAE

Scientific Name:

Pseudibis davisoni

Species Authority:

(Hume, 1875)

Common Name/s:

English

–

White-shouldered Ibis

Assessment Information [top]

Red List Category & Criteria:

Critically Endangered A3c ver 3.1

Year Assessed:

2011

Assessor/s:

BirdLife International

Reviewer/s:

Symes, A., Butchart, S.

Contributor/s:

Wright, H., Clements, T., Evans, T., Timmins, R., Eames, J.

Justification:
This species has an extremely small and fragmented population as a result of deforestation, drainage of wetlands, hunting, disturbance and potentially a number of unknown factors, and is projected to undergo an extremely rapid population decline over the next three generations (25 years). It therefore qualifies as Critically Endangered. If conservation efforts succeed in bringing the largest remaining populations, in north-eastern Cambodia and along the Mekong channel, under effective protection, the species may warrant downlisting.

History:

2010	–	Critically Endangered
2009	–	Critically Endangered
2008	–	Critically Endangered
2004	–	Critically Endangered
2000	–	Critically Endangered
1996	–	Endangered
1994	–	Endangered

Geographic Range [top]

Range Description:	This species now occurs in northern and eastern Cambodia (at least 90% of the global population)¹⁴, extreme southern Laos and East Kalimantan, Indonesia. It was previously widely but patchily distributed across much of Thailand, Laos, south and central Vietnam and Cambodia, parts of Myanmar, Kalimantan (Indonesia), Sarawak (Malaysia) and south-west Yunnan, China, but has declined dramatically during the 20th century. It is extinct in Thailand and there are no recent records from Myanmar; and it has been described as the most threatened large waterbird in South-East Asia based on the widespread declines observed⁵. It is almost certainly extinct as a breeding species in Vietnam and now only occurs as a rare non-breeding visitor. In Cambodia significant populations are known from Siem Pang District (minimum 200 individuals)¹⁴, Lomphat Wildlife Sanctuary in Ratanakiri (minimum 170)¹⁸, and along the Mekong river channel between Kratie and the Laos border (c.75-125 individuals)⁷. In 2009, 12 nests were found in Western Siem Pang, 7 successfully, fledging a total of 14 chicks¹⁶. Tmatboey, in the Northern Plains, Cambodia, supports a population recorded at 15-20 birds at the end of the 2007 breeding season. Additional groups (1-10 birds each) have been recorded elsewhere, particularly from the south-eastern shore of the Tonle Sap lake, Srepok river and the O Te lowlands, while it has also been found in Mondulkiri Province, the latter representing a southern extension of its known range in the country⁶, and it might be found further south still in Kompong Cham province along the Mekong^7,8. Early dry season counts at Western Siem Pang IBA have increased in recent years, from 23 in January 2003 to over 200 in 2010^13,18. The reasons behind this apparent increase are unknown: it may result from improved survey effort or a greater abundance of feeding locations as a consequence of human habitat modification^7,8. In Kalimantan, the population at the main locality along the Mahakam River was estimated at 30-100 individuals, but recent studies reveal a decline following extensive El Niño Southern Oscillation (ENSO)-derived forest fires².
Countries:	Native: Cambodia; Indonesia; Lao People's Democratic Republic Possibly extinct: China; Myanmar
Range Map:	Click here to open the map viewer and explore range.

Population [top]

Population:	The Indonesian population was estimated at 30-100 individuals (BirdLife International 2001) but has apparently declined (Sözer and Nijman 2005). A nationwide coordinated count of the species in Cambodia in 2010 recorded a total of 429 individuals and the population is thought to be even larger (BirdLife International 2010). Based on this survey data, a minimum population of 450 individuals seems appropriate.
Population Trend:	Decreasing

Population:

The Indonesian population was estimated at 30-100 individuals (BirdLife International 2001) but has apparently declined (Sözer and Nijman 2005). A nationwide coordinated count of the species in Cambodia in 2010 recorded a total of 429 individuals and the population is thought to be even larger (BirdLife International 2010). Based on this survey data, a minimum population of 450 individuals seems appropriate.

Population Trend:

Decreasing

Habitat and Ecology [top]

Habitat and Ecology:	Wetlands and grassland, such as pools, marshes, open grasslands or watercourses including wide rivers with sand and gravel bars were formerly important for the species, however at least in Indochina deciduous dipterocarp forest (which is usually inundated during the wet season) now appears to be of major importance¹¹. Trapaengs (seasonal pools) are particularly favoured during the dry season, with a shift to matrix sites such as fallow rice fields and the dipterocarp forest itself after rainfall events¹². The species has been recorded along large rivers such as the Mekong in Cambodia and on the Mahakam in Kalimantan. It is also been recorded from the mosaic of shrub and grasslands on the Tonle Sap floodplain. In Cambodia it has been recorded nesting during the dry season (December-April) on the edges of seasonally abandoned wet season rice paddy and in the Mekong channel. Two nests in Kalimanan were located at 30 m and 40 m height in tall trees along tributaries of the Mahakam river - the main breeding here may be from at least September-December¹⁷. It has been observed feeding in soft substrates on the forest floor as well as at small waterbodies³; also in sediment formations in river channels. Amphibians were the most common prey type consumed by White shouldered Ibis. Also important were molecrickets, which during the dry season occur in the mud at trapaengs. The other prey such as invertebrate, leeches, snails, and eels¹⁴. In South-East Asia the species may be associated with large ungulates which may help to create and maintain seasonal pools within the dry forest landscape⁴, and its preference for trapaengs with bare substrate and low vegetation supports this theory¹². Large wild ungulates have now all but disappeared from the region, and the species may now be more closely associated with domestic livestock¹¹. Available evidence gives no suggestion that the species undertakes major seasonal movements. White-shouldered Ibis aggregate into large flocks (max. count of 173 individuals in Siem Pang District, Cambodia¹³).
Systems:	Terrestrial; Freshwater

Habitat and Ecology:

Wetlands and grassland, such as pools, marshes, open grasslands or watercourses including wide rivers with sand and gravel bars were formerly important for the species, however at least in Indochina deciduous dipterocarp forest (which is usually inundated during the wet season) now appears to be of major importance¹¹. Trapaengs (seasonal pools) are particularly favoured during the dry season, with a shift to matrix sites such as fallow rice fields and the dipterocarp forest itself after rainfall events¹². The species has been recorded along large rivers such as the Mekong in Cambodia and on the Mahakam in Kalimantan. It is also been recorded from the mosaic of shrub and grasslands on the Tonle Sap floodplain. In Cambodia it has been recorded nesting during the dry season (December-April) on the edges of seasonally abandoned wet season rice paddy and in the Mekong channel. Two nests in Kalimanan were located at 30 m and 40 m height in tall trees along tributaries of the Mahakam river - the main breeding here may be from at least September-December¹⁷. It has been observed feeding in soft substrates on the forest floor as well as at small waterbodies³; also in sediment formations in river channels. Amphibians were the most common prey type consumed by White shouldered Ibis. Also important were molecrickets, which during the dry season occur in the mud at trapaengs. The other prey such as invertebrate, leeches, snails, and eels¹⁴. In South-East Asia the species may be associated with large ungulates which may help to create and maintain seasonal pools within the dry forest landscape⁴, and its preference for trapaengs with bare substrate and low vegetation supports this theory¹². Large wild ungulates have now all but disappeared from the region, and the species may now be more closely associated with domestic livestock¹¹. Available evidence gives no suggestion that the species undertakes major seasonal movements. White-shouldered Ibis aggregate into large flocks (max. count of 173 individuals in Siem Pang District, Cambodia¹³).

Systems:

Terrestrial; Freshwater

Threats [top]

Major Threat(s):	It has declined as a result of habitat loss, through logging, widespread piecemeal clearance of lowland forest, conversion of wetlands for agriculture (most of the Mekong floodplain in southern Laos has been converted to rice-paddy) and agro-industrial and infrastructure development (such as the proposed dams on the River Srepok¹¹). Habitat loss has been compounded by hunting of adult birds, eggs and chicks for food, and disturbance, leading to the loss of secure feeding, roosting and nesting areas⁸. The hunting pressure is exacerbated by the fact that their primary habitats appear to be also a focus of people: large rivers and grassland/field complexes with high densities of ungulates and domestic livestock, however hunting may now be less of a threat in Cambodia following education initiatives and the confiscation of weapons¹¹. Recent evidence suggests that forest fires in Borneo resulting from an El Niño Southern Oscillation (ENSO) event shifted the distribution of this species to unburnt stretches of rivers². There is considerable evidence that the species is associated with large ungulates in South-East Asia which create and maintain the short-sward grassland feeding areas that the ibises depend upon within the dry forest landscape⁴. Hence, the demise of wild ungulates within the region may have catalysed its rapid decline resulting in no remote refugia for the species^7,8. Moreover, its dependency on herbivore-altered habitats means that remnant areas are close to people and associated with domestic livestock, making it more vulnerable to human induced habitat modification^7,8. Probably the most significant threats currently come from land concessions for logging or plantations, and infrastructure development such as dam construction, which threaten even those areas that currently have protected status¹¹.

Major Threat(s):

It has declined as a result of habitat loss, through logging, widespread piecemeal clearance of lowland forest, conversion of wetlands for agriculture (most of the Mekong floodplain in southern Laos has been converted to rice-paddy) and agro-industrial and infrastructure development (such as the proposed dams on the River Srepok¹¹). Habitat loss has been compounded by hunting of adult birds, eggs and chicks for food, and disturbance, leading to the loss of secure feeding, roosting and nesting areas⁸. The hunting pressure is exacerbated by the fact that their primary habitats appear to be also a focus of people: large rivers and grassland/field complexes with high densities of ungulates and domestic livestock, however hunting may now be less of a threat in Cambodia following education initiatives and the confiscation of weapons¹¹. Recent evidence suggests that forest fires in Borneo resulting from an El Niño Southern Oscillation (ENSO) event shifted the distribution of this species to unburnt stretches of rivers². There is considerable evidence that the species is associated with large ungulates in South-East Asia which create and maintain the short-sward grassland feeding areas that the ibises depend upon within the dry forest landscape⁴. Hence, the demise of wild ungulates within the region may have catalysed its rapid decline resulting in no remote refugia for the species^7,8. Moreover, its dependency on herbivore-altered habitats means that remnant areas are close to people and associated with domestic livestock, making it more vulnerable to human induced habitat modification^7,8. Probably the most significant threats currently come from land concessions for logging or plantations, and infrastructure development such as dam construction, which threaten even those areas that currently have protected status¹¹.

Conservation Actions [top]

Conservation Actions:	Conservation Actions Underway It occurs in several protected areas including Kulen Promtep Wildlife Sanctuary (documented breeding population), Lomphat Wildlife Sanctuary, Preah Vihear Protected Forest, Mekong Ramsar site, Ang Trapeang Thmor, Seima Biodiversity Conservation Area, Srepok Wilderness Area (part of the Mondulkiri Protected Forest), Integrated Farming and Biodiversity Areas, Cambodia, and Xe Pian National Protected Area (NPA), Laos. It is depicted on public awareness material distributed in Laos and Cambodia. The species is considered to be the most threatened large waterbird in South-East Asia and was a priority species during the designation of Cambodian IBAs and priority areas for conservation in the 'dry forest ecoregion' of South-East Asia⁵. Research has been conducted into the species's foraging ecology and nesting in Kulen Promtep Wildlife Sanctuary and Western Siem Pang¹⁶, Cambodia, and is planned for other areas. A nest protection scheme with incentives to local people for protecting nest-sites along the Mekong¹ and in the Lomphat Wildlife Sanctuary is being established. A PhD studying the species's foraging ecology began in 2008. A community-managed ecotourism initiative has been established at Tmatboey. As part of BirdLife's Preventing Extinctions programme the following actions are being implemented by the Species Guardian: 1. A proposal to establish a Protected Forest in Western Siem Pang has been prepared, reviewed, revised and approved by the Provincial Governor and the steering committee of Ministry Agriculture Forestry and Fisheries. The Governor of Stung Treng issued an official letter, and the steering committee of Ministry of Agriculture Forestry and Fisheries have endorsed a draft sub-decree in support of the proposal to designate Western Siem Pang a Protected Forest¹⁶. 2. The government have been lobbied to complete the notification process, including through producing a poster about the international importance of Western Siem Pang for conservation and distributing this to all relevant governmental and non-governmental stakeholders. Large information boards were placed in five key villages within the IBA to inform local people about development plans and threats to their land from proposed concessions. 3. Research and monitoring continues to be carried out, focusing on the foraging ecology of the species and examining the influence of traditional land management practices. 4. A Local Conservation Group at Western Siem Pang has been supported since August 2007, and conducts monthly patrols to the most important trapaengs to record key species and any illegal activities. A Site Support Group is being established in Lomphat Wildlife Sanctuary in order to support managment, protecting and monitoring at the sanctuary. In 2009, one chainsaw, 6.834 m³ of luxury wood, four guns, and one ox-cart were confiscated and destroyed in Western Siem Pang as result of information provided by the patrol team¹³. Conservation Actions Proposed Finalise the establishment of a Protected Forest in Western Siem Pang¹. Continue monitoring the known populations in Siem Pang, Northern Plains and Mekong channel and in other parts of its range as well as researching the ecological requirements of the species¹. Conduct further surveys in Borneo, central, northern and eastern Cambodia and the Satay area of Vietnam to quantify remaining populations, only in areas where conservation intervention is considered reasonable and there are grounds for considering a significant population might be found. Establish further protected areas or integrated conservation development projects covering landscape-level habitat tracts supporting populations, particularly in northern Cambodia and along the Mahakam river, East Kalimantan. Enforce strict protection at important sites. Promote widespread conservation awareness programmes aimed at reducing wetland disturbance and large waterbird exploitation in Indochina.

Conservation Actions:

Conservation Actions Underway
It occurs in several protected areas including Kulen Promtep Wildlife Sanctuary (documented breeding population), Lomphat Wildlife Sanctuary, Preah Vihear Protected Forest, Mekong Ramsar site, Ang Trapeang Thmor, Seima Biodiversity Conservation Area, Srepok Wilderness Area (part of the Mondulkiri Protected Forest), Integrated Farming and Biodiversity Areas, Cambodia, and Xe Pian National Protected Area (NPA), Laos. It is depicted on public awareness material distributed in Laos and Cambodia. The species is considered to be the most threatened large waterbird in South-East Asia and was a priority species during the designation of Cambodian IBAs and priority areas for conservation in the 'dry forest ecoregion' of South-East Asia⁵. Research has been conducted into the species's foraging ecology and nesting in Kulen Promtep Wildlife Sanctuary and Western Siem Pang¹⁶, Cambodia, and is planned for other areas. A nest protection scheme with incentives to local people for protecting nest-sites along the Mekong¹ and in the Lomphat Wildlife Sanctuary is being established. A PhD studying the species's foraging ecology began in 2008. A community-managed ecotourism initiative has been established at Tmatboey. As part of BirdLife's Preventing Extinctions programme the following actions are being implemented by the Species Guardian: 1. A proposal to establish a Protected Forest in Western Siem Pang has been prepared, reviewed, revised and approved by the Provincial Governor and the steering committee of Ministry Agriculture Forestry and Fisheries. The Governor of Stung Treng issued an official letter, and the steering committee of Ministry of Agriculture Forestry and Fisheries have endorsed a draft sub-decree in support of the proposal to designate Western Siem Pang a Protected Forest¹⁶. 2. The government have been lobbied to complete the notification process, including through producing a poster about the international importance of Western Siem Pang for conservation and distributing this to all relevant governmental and non-governmental stakeholders. Large information boards were placed in five key villages within the IBA to inform local people about development plans and threats to their land from proposed concessions. 3. Research and monitoring continues to be carried out, focusing on the foraging ecology of the species and examining the influence of traditional land management practices. 4. A Local Conservation Group at Western Siem Pang has been supported since August 2007, and conducts monthly patrols to the most important trapaengs to record key species and any illegal activities. A Site Support Group is being established in Lomphat Wildlife Sanctuary in order to support managment, protecting and monitoring at the sanctuary. In 2009, one chainsaw, 6.834 m³ of luxury wood, four guns, and one ox-cart were confiscated and destroyed in Western Siem Pang as result of information provided by the patrol team¹³.

Conservation Actions Proposed
Finalise the establishment of a Protected Forest in Western Siem Pang¹. Continue monitoring the known populations in Siem Pang, Northern Plains and Mekong channel and in other parts of its range as well as researching the ecological requirements of the species¹. Conduct further surveys in Borneo, central, northern and eastern Cambodia and the Satay area of Vietnam to quantify remaining populations, only in areas where conservation intervention is considered reasonable and there are grounds for considering a significant population might be found. Establish further protected areas or integrated conservation development projects covering landscape-level habitat tracts supporting populations, particularly in northern Cambodia and along the Mahakam river, East Kalimantan. Enforce strict protection at important sites. Promote widespread conservation awareness programmes aimed at reducing wetland disturbance and large waterbird exploitation in Indochina.

Citation:	BirdLife International 2011. Pseudibis davisoni. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.2. <www.iucnredlist.org>. Downloaded on 09 February 2012.
Disclaimer:	To make use of this information, please check the <Terms of Use>.
Feedback:	If you see any errors or have any questions or suggestions on what is shown on this page, please fill in the feedback form so that we can correct or extend the information provided