Avian demography: statistics and ornithology

Avian demography is defined here as the study of the statistics of bird populations. Ornithology has generated types of data - or been the first discipline to generate them - which do not lend themselves to standard statistical analyses. In these situations, the role of the avian demographer is to develop custom-built statistical methods - the analysis of primary moult is an example of a type of data needing specialised methods and this is discussed in the final sections of the paper. Data from the Southern African Bird Atlas Project is used to present some insights into the biogeography of southern African birds, and to describe the 'texture' of bird distributions. The year 1998 marks, approximately, the centenary of the introduction of the European Starling Sturnus vulgaris to Cape Town and the House Sparrow Passer domesticus to Durban, and the paper notes this event and these species.