A new framework for classifying the positive impacts of non-native species will allow conservationists and policy makers to make more informed management decisions, according to a Consensus Watch article by Giovanni Vimercati of the University of Fribourg, Switzerland, and colleagues, published on 16 August in the open access journal PLOS Biology.
The Environmental Impact Classification of Alien Taxa, or EICAT, developed in 2014 and officially adopted by the International Union for the Conservation of Mother Nature (IUCN) in 2020, is a worldwide standard for assess the impact of non-native species. Yet the framework only assesses negative impacts on native species. However, non-native species can also have positive impacts on native biodiversity where they are introduced, for example by providing new food sources or new habitats that increase the population of native species or prevent their decline and extinction. .
To achieve a more complete and holistic understanding of the impacts caused by non-native species, researchers have developed a parallel framework to assess their positive impacts on the native biodiversity, called EICAT+, in consultation with experts. EICAT+ assesses non-native species using five semi-quantitative scenarios that describe the magnitude of positive impacts. The framework also considers the mechanisms underlying these impacts and how quickly their effects could be reversed if non-native species were eradicated.
The EICAT+ framework can be applied at different spatial scales, from local to world-wide, and at different levels of organization, from individuals to populations, as well as to all taxonomic groups. This can help identify knowledge gaps and expand scientific understanding of the consequences of biological invasions. The framework can also inform conservation decisions by highlighting potential adverse effects of planned control or eradication measures that target non-native species, according to the authors.
Dr. Vimercati adds: “Recognizing that non-native species have multifaceted impacts on native biodiversity, we have developed a new, standardized, evidence-based framework for positive impacts that was not previously available. EICAT+ fills a critical gap in the field and can be used, among other things, to assess how non-native animals or plants deployed in biological control and restoration contribute to conservation goals.
BiodiversityEnvironmentFribourgEnvironmental ImpactOpen AccessSwitzerlandInternational Union for the Conservation of NatureUniversity