Mainstreaming ecological connectivity in road environmental impact assessments: a long way to go

Abstract

Road networks affect ecological connectivity, which has implications across different levels of biological organization. There are compelling reasons and sufficient approaches and tools to mainstream ecological connectivity into environmental impact assessments (EIAs) of road projects. In this letter, we discuss ways of overcoming the existing gaps and obstacles in the consideration of connectivity loss in EIAs and how to improve mitigation. The selection of target species, shifting from single to multispecies approaches, and the evaluation of scale optimization are challenges that need to be overcome. We also discuss that the mitigation hierarchy, no net loss targets, and the principles of adaptive management should be applied to increase the effectiveness of mitigation measures. We propose to increase the cooperation between stakeholders and practitioners to enhance co-production and build capacity to conduct evidence-based EIAs for assessing ecological connectivity. Finally, we identify directions for future research that can contribute to integrating connectivity into EIA practice.