posted on December 29, 2009 10:25
There are many threatened bird species that can be seen in the Northern Plains landscape. This page contains information on aspects such as the population status and breeding habits of some of the key species.
White-shouldered Ibis Pseudibis davisoni
Until recently, the only known breeding site for this Critically Endangered species on mainland South-East Asia was around Tmatboey in Kulen Promtep Wildlife Sanctuary. Its numbers since breeding was first discovered here in 2002 have increased gradually and from a single pair, 43 birds were found roosting at this site in 2009. Aside from at regular roosts, it can be seen feeding at small ponds and in wet conditions in dry, open forest.
Giant Ibis Pseudibis gigantea
The Giant Ibis is Cambodia's national bird and the majority of the global population of this species occurs in the Northern Plains. The bird was thought to be almost extinct before its rediscovery here in 2003, hence its status of Critically Endangered. The population has remained stable or possibly increased since breeding was first found in 2003. In 2009 41 pairs bred produced a record 53 chicks. Its loud calls can be heard across the Northern Plains in the early hours of the morning and it is often seen at small ponds and larger flooded areas around the landscape.
Sarus Crane Grus antigone
Sarus Cranes are a Vulnerable species found in three distinct populations in South Asia, South-East Asia and Australia; the subspecies sharpii is found in Myanmar, southern Laos, Vietnam and Cambodia. The largest flock of cranes feeds at An Trapeang Thmor in north-west Cambodia in the non-breeding season, and with the rains this flock flies east to the Northern Plains in May and June. Breeding numbers in the Northern Plains have increased to over 50 pairs from 2004-2009 which is the largest breeding population in the region. The bugling calls of this species are most often heard in the wet season in open grasslands, but some birds remain all year in the Northern Plains.
Lesser Adjutant Leptoptilos javanicus
Lesser Adjutants have thrived in recent years in Preah Vihear. The small population of 34 pairs at five colonies in 2003 increased to over 250 pairs producing nearly 500 chicks in 2008. The population rivals that of the Tonle Sap which has also increased to just over 300 pairs. This Vulnerable species is now relatively secure in Cambodia, but it is still threatened by clearance of forest, nest-raiding by people and timber-cutting of nesting trees. This species is commonly seen at wetlands in both open woodland and dense forest.
Greater Adjutant Leptoptilos dubius
This species has proved difficult to protect in the Northern Plains. It breeds at a remote colony which is subject to many threats and its feeding sites are also difficult to manage. The population of 21 pairs in 2004 has declined to a handful of pairs as a result of these problems. However, recent conservation actions, including construction of a new patrol station, will improve management of the breeding area for this bird and we expect the population to recover and match the success of the Tonle Sap population. This bird is rarely seen away from its main feeding areas along floodplains, but between September and November it can sometimes be found at vulture restaurants.
Black-necked Stork Ephippiorhynchus asiaticus
The Near-Threatened Black-necked Stork is one of the scarcest large water birds in Cambodia. It has bred in Tonle Sap, but the best known breeding population is in the Northern Plains where 2-3 nests are found each year. It can be found feeding at small ponds in the dry season.
White-rumped Vulture Gyps orientalis
Between 30-50 individuals of this Critically Endangered species can be seen regularly at the monthly vulture restaurant in Preah Vihear Protected Forest. This may now be the most important feeding site for this species in the country. A small colony of 3-4 pairs breeds each year at this site and this is protected by our bird nest protection program. This species is highly social and constitute the majority of vultures at carcasses.
Slender-billed Vultures Gyps tenuirostris
This Critically Endangered species does not breed in the Northern Plains, but from 5-10 birds are seen at each monthly restaurant in Preah Vihear Protected Forest. The total population in Cambodia is up to 50 birds (and less than 1,000 remain globally), so this site is of some importance. This bird is much larger than the other resident vultures and dominates carcasses.
Red-headed Vulture Sarcogyps calvus
This is the second of the breeding Critically Endangered vultures found in the Northern Plains. Two to three pairs breed across the landscape each year and up to 15 birds can be seen at restaurants. This species, although larger than the White-rumped Vulture, is less social and dominant and will wait until other species have finished feeding before entering the fray at restaurants.
White-winged Duck Cairina scutulata
White-winged Ducks are an Endangered species found across the Northern Plains in forested rivers and wetlands. They are highly secretive and elusive and are very difficult to observe. One nest was found in Kulen Promtep Wildlife Sanctuary in 2008 and it is believed they breed at several other sites. However, as they breed at the height of the floods it is often difficult to access the forests to find nests.
Oriental Darter Anhinga melanogaster
Oriental Darters are commonly seen on larger wetlands and rivers in the Northern Plains. When rainfall and flooding create exactly the right conditions they breed in small numbers in the landscape. From 2006-2009 flooding has been high enough to permit breeding and they successfully raised chicks in 3 of the 4 years: crows are often the most important predator of their nests. This is a small proportion of the many thousands that breed on the Tonle Sap lake each year.
Masked Finfoot Heliopais personata
One of the least known birds in tropical Asia, the Endangered Masked Finfoot has very few scattered records in Cambodia. In 2009 a nest with eggshells was found in Kulen Promtep Wildlife Sanctuary was found during the floods. Several pairs were seen along a forested river. This is an exciting discovery and much more remains to be understood about its distribution and ecology in the Northern Plains.
Other threatened species
These species of global conservation concern are also found in the Northern Plains of Cambodia. They are frequently sought by visiting birders as they are globally threatened and some are rare outside the deciduous dipterocarp forest that is found in the Northern Plains, but has been cleared elsewhere.
Threatened passerines include Manchurian Reed WarblersAcrocephalus tangorum (Vulnerable), which winters locally in sedge beds and Sesbania scrub fringing trapeangs, and small numbers of Asian Golden Weavers Ploceus hypoxanthus (Near-Threatened) can be found amongst the mixed flocks of the more numerous Baya Ploceus philippinus and Streaked Weavers Ploceus manyar in the area.
Pale-capped Pigeon Columba punicea
This Vulnerable species is a regular sighting at Tmatboey, which is one of very few locations in the region where this rare pigeon can be reliably found. The birds congregate in stands of bamboo along rivers, possibly in response to flowering events. When water levels are low they are commonly seen at Trapeang Chamres Khel, a permanent pool in a seasonal river to the north-west of the village near to one of the Giant Ibis nesting sites.
White-rumped Falcon Polihierax insignis
White-rumped Falcons occur at low densities, but is periodically recorded around Tmatboey, especially at Kohkoh Tnal and at other sites in the landscape. This Near-threatened species has been found breeding near O Koki in Preah Vihear Protected Forest.
Mystery Aquila Eagles
One mystery yet to be unravelled is the occurrence of unidentifiedAquila eagles that show a number of plumage similarities with first winter Indian Spotted Eagle Aquila hastata, in particular the combination of a broad, diffusely white patch at the base of the primaries, distinctly paler lesser and median upperwing coverts, darker greater coverts with pale tips and some white in the scapular region. Any visiting birders with cameras are urged to photograph any Aquila eagles (including Greater Spotted) and are politely requested to send the photographs to WCS. Note,fulvescens morph Greater Spotted Eagle also occurs.