The Southern African Bird Atlas Project and its relevance to nature conservation

[摘要] ENGLISH SUMMARY: The objectives of this thesis are to: (a) describe the Southern African Bird Atlas Project(SABAP), document its progress and assess its success, as a contribution to theplanning of future projects; (b) explore the potential of atlas data to answer questionsother than those concerned with the ranges of species; (c) investigate the application ofbird atlas data to some specific questions which have a bearing on the planning andpractice of conservation.The progress and organizational features of SABAP and its databank are described. Itis shown that the SABAP has been a success in terms of the large volumes of accurateand up-to-date data on species' distributions and patterns of seasonality acquired. Thedecision to use amateur volunteers is shown to have been appropriate but not withoutdrawbacks.A methodological point made is that the methods of atlasing and of computerization ofthe data need to be planned so as to permit statistical analysis of the data. If this isdone, reporting rates can provide an index of relative abundance which can, in tum,permit the application of atlas data to many questions beyond that of range extent.The analysis of reporting rates is illuminating in the description of seasonal patterns ofoccurrence and therefore, of seasonal movement. This is demonstrated for long-distancemigration and for local movement. The papers dealing with patterns ofseasonality highlight the fact that species with extensive seasonal movements cannot beconserved within, single reserves.The growing demand for access to SABAP data is reported and the applications listed.Improvement of SABAP's relevance to the environmental consultancy user group isachieved by a method of presenting atlas data in a manner which will maximize theirusefulness. The approach hinges on the ability to allocate species to habitat categories. This enables one to break down an undifferentiated species list for a grid square into anumber of habitat-specific species lists.It is proposed that atlasing could be adapted to achieve population monitoringobjectives. One exercise set out to analyse changes in reporting rate through time andto correlate these with a key environmental variable, namely rainfall. The exercise isonly a limited success. It is shown that, while potential to use atlas methods for population monitoring does exist, the need to improve the standardization of methods for this purpose is crucial.Interim results of the SABAP in the form of species distribution maps are presented asan aid to the planning of conservation action for cranes. The information for the threespecies is compiled to produce a map which highlights those grid squares which havethe greatest diversity of cranes. It is shown that the combination of atlas informationfor a suite of species can yield an index of diversity which may hold greater potentialfor planning the location of reserves than the distribution maps of individual speciesalone.Trends in bird atlasing and of the use of reporting rate as an index of relativeabundance are reviewed as is the use of reporting rates as a population monitoring tool.

[发布机构] Stellenbosch University