Simon Mustoe is a research consultant with Ecoscope Applied Ecologists. He graduated in ecology from the University of East Anglia in 1995 after which he led a multi-national team of researchers to Madagascar as part of an integrated conservation development project, part funded by the BirdLife/FFI/BP Conservation Program. He has worked both as a bird researcher at the RSPB and as an assistant to the African Important Bird Areas (IBA) project at BirdLife International. Simon specializes in ornithological assessments, being familiar with a wide range of different methods and having worked in a range of situations as diverse as tropical forests and the Northeast Atlantic. His experience of modern methods of large scale surveys using distance sampling, led to his being involved in the important task of bringing these chapters up to date.