Scientists develop ranking system to scale the impact of alien species

A transparent ranking system for measuring the socio-economic impact of plants and animals that are introduced by humans to areas where they do not naturally occur (termed "aliens") has been developed by an international team of scientists, from UCL, Université de Fribourg and Stellenbosch University. The 'Socio-Economic Classification of Alien Taxa (SEICAT)', described in a study published today in Methods in Ecology and Evolution and supported by an EU COST Action grant, will help to capture the impact that alien species have on human livelihood and well-being. "Alien species can cause harm in many ways in areas to which they are introduced. Besides the effects on biodiversity, which can lead to extinctions of native species and transformations of whole landscapes and ecosystems, they can also have wide-ranging effects on human health, livelihoods, and well-being," said Professor Tim Blackburn, Chair of Invasion Biology at UCL. The Tiger Mosquito, Aedes albopictus, in South-east Asia is spreading devastating diseases like Dengue, and is therefore considered a significant threat to human well-being in many countries around the world. However, it is not only diseases and insects which are problematic to humans. The Cane Toad, Rhinella marina, which was first introduced to Australia to control a crop pest subsequently spread exponentially and devastated the countries native species.