White-shouldered Ibis (Pseudibis davisoni)

Mohamed bin Zayed Species project number 1005578

White-shouldered ibis Pseudibis davisoni is the most threatened of South-East Asia’s waterbirds (Tordoff et al., 2005). Having previously occurred across Indochina, including Thailand, Myanmar, Laos and Vietnam, the majority of white-shouldered ibis remaining globally are in Cambodia. The surviving fragmented population may only comprise of 50-249 mature individuals (BirdLife International, 2009), although 310 birds were counted this year (HL Wright unpublished data 2009). The largest known populations are in unprotected areas. The reasons for this critically endangered species’s decline are not well understood, although hunting and habitat destruction are likely factors.

White-shouldered ibis are canopy-nesting solitary breeders, raising 1-3 chicks in the tropical dry season (November to April). Nest protection has been implemented in parts of Cambodia since 2003 despite a lack of evidence regarding its necessity or any evaluation of alternative appropriate techniques to enhance breeding success. In 2008, UEA initiated a PhD project to investigate aspects of ibis ecology to directly inform and guide conservation interventions. UEA discovered a 65% nest failure rate during incubation and brooding, with natural and / or human predation the likely cause. Understanding and successfully preventing predation will provide an urgently-needed improvement in white-shouldered ibis breeding productivity.

The objectives of our project are to:

• Determine the relative importance of human versus natural predation for white-shouldered ibis nest success
• Determine the relative importance of different predator species for white-shouldered ibis nest success
• Implement a nest guarding scheme and monitor its outcome to study the effectiveness of guarding as a nest protection measure
• Make recommendations for effective nest protection measures and consult conservation NGOs about their implementation
• Build capacity of local field staff to independently implement nest monitoring and nest protection scheme.
• Raise awareness of the importance of key dry dipterocarp forest landscapes and provide scientific evidence to support advocacy for their urgent protection