A bioclimatic analysis for the highly mobile Superb Parrot of south-eastern Australia

Abstract

The aim of this study was to define the bioclimatic domain of the Superb Parrot (Polytelis swainsonii) of south-eastern mainland Australia using the BIOCLIM modelling software, and to make predictions of its geographical range. The strengths and limitations of BIOCLIM analysis, with particular reference to the Superb Parrot are discussed. A bioclimatic profile based on 115 observations of the species was produced. Seven key parameters were chosen from the bioclimatic profile, and then matched with other locations with similar climatic conditions to predict the potential geographical distribution. Bioclimatic analysis indicated general correspondence between the location of Superb Parrot observations and the predicted ‘core’ area. Owing to habitat loss and modification, it is likely that the Superb Parrot occupies a relatively small part of its former geographical range. Hence, some areas that are bioclimatically optimal may no longer support resources needed by the Superb Parrot. BIOCLIM has several limitations, not least of which is that climatic tolerances are only one of many factors that influence the ‘extent of occurrence’ of species. Although BIOCLIM has some problems when used to study highly mobile birds like the Superb Parrot, the approach provides a useful starting point for further investigations, and has an important role to play in defining potential geographical ranges.