Universal framework for assessing the environmental impact of marine non-indigenous species in different situations of data availability

Current methods for assessing the environmental impacts of marine non-indigenous species (NIS) are limited by insufficient data, an over-reliance on expert judgement and too coarse a spatial resolution, which hampers accurate local management. However, advances in data-driven analyses offer significant potential for developing more comprehensive and accurate frameworks for assessing the impacts of NIS in marine ecosystems. This study fills this major gap in NIS management by proposing a comprehensive and practical framework that integrates systematic reviews, meta-analyses, species distribution modelling, and expert judgement to assess NIS impacts across varying levels of information availability. The framework also recommends complementary, under-utilised data sources, and tools to reduce significantly existing information constraints. The framework presented in this study not only advances scientific understanding of NIS impacts by providing a scalable and adaptable framework for assessing NIS impacts in different ecological contexts, but also provides practical tools for environmental managers implementing legislation on NIS. We recognise that although our data-driven approach to NIS management is best handled by specialists, maximising its potential requires making the information accessible and user-friendly to a broader audience. This can be achieved through digital tools that simplify and facilitate the understanding of these assessments for environmental managers.