[1
]Centre for Biological Diversity; University of St Andrews; Harold Mitchell Building
St Andrews Fife KY16 9TH UK
[2
]AP Leventis Ornithological Research Institute; Jos Nigeria
[3
]RSPB Centre for Conservation Science; The Lodge; Sandy Beds SG19 2DL UK
[4
]Fauna & Flora International; 2 Harmon's Compound, Oldest Congo Town Monrovia Liberia
[5
]Centre for Integrative Ecology; Deakin University; Geelong Vic. 3216 Australia
[6
]British Trust for Ornithology; The Nunnery Thetford IP24 2PU UK