Formulating conservation targets for biodiversity pattern and process in the Cape Floristic Region, South Africa

Abstract

The Cape Floristic Region of South Africa is a global biodiversity hotspot. In 1998, a process of conservation planning began in the region that required quantitative targets for biodiversity. We combined new information and previously available data sets on biodiversity pattern and process to formulate targets for five groups of features: 102 broad habitat units (land types); locality records for 364 plant species in the family Proteaceae; locality records for 345 species of reptiles, amphibians and freshwater fish; estimated distributions and densities of 41 species of large and medium-sized mammals; and six types of spatial surrogates for ecological and evolutionary processes. We discuss our approach to formulating quantitative targets in the context of the general role of targets in conservation planning, the inadequacy of commonly used standard targets such as 10% of features or whole regions, and the uncertainties around setting targets for land types. We then describe our reasoning and methods for analysing data and identifying targets for each group of features. Our targets are not theoretical—they have been used to develop a regional conservation plan for which implementation is underway. Our targets are, however, provisional. Like any other conservation targets, they are estimates of the requirements for persistence of a region's biodiversity made within the constraints of limited information. We expect them to be improved in future reviews of appropriate targets for the Cape Floristic Region and elsewhere.