Pests, pathogens and poverty: Biological invasions and agricultural dependence

Introduction The problem addressed in this paper is the linkage between poverty and invasive alien species (IAS) - the introduction, establishment and spread of species outside of their original range. There are two main dimensions to the problem. One is the connection between poverty and the likelihood of the introduction, establishment or spread of invasive species. It includes the relation between poverty and strategies for the management of invasive species, investment in invasive species detection and control, and collaboration in international control measures. The second is the connection between poverty and the costs or benefits of invasions. This includes the links between invasive species, the structure of the economy, and poverty. It covers the relation between poverty and dependence on agriculture, wildlife utilisation, forestry and fisheries, and the importance of common property. These two dimensions have been addressed in three generally distinct literatures. One is the literature on the costs of biological invasions. It is closely associated with the work of David Pimentel and colleagues, and comprises estimates of the more direct costs of invasive pests and pathogens in selected countries, including at least some developing countries (South Africa, India and Brazil). It also includes a longer-standing literature on the costs of various animal and plant pests and pathogens in agriculture, forestry and - to a lesser extent - fisheries. A second is on economics of invasive species.