Death by a dozen cuts: Mitigation of biodiversity impacts from Development Corridors in Africa

Infrastructure development is fundamental for improving human well-being, but at the same time it can degrade natural habitats and ecological processes, leading to negative outcomes for biodiversity and people. In this thesis I study the tension between development and conservation, by examining a specific type of infrastructure development named Development Corridors. Development Corridors are national or transnational spatial development initiatives that include large infrastructure projects and associated industries, sometimes with accompanying policies, plans and programmes. I start by bringing some clarity to the development corridor terminology and then carry out a global review of biodiversity impact mitigation in development corridors. I show that Development Corridor approach is a widespread global phenomenon present in all continents except Antarctica. I find that best practice in biodiversity impact mitigation is rarely applied in the Development Corridor approach, as described in the literature. This includes a poor application of the mitigation hierarchy and very few assessments of indirect and cumulative impacts on biodiversity and ecosystem services. The rest of my thesis focuses on continental Africa as part of the Development Corridors Partnership (DCP) project. Collaborating with DCP researchers, I co-led the creation of the first African Development Corridors database and show that there were more than twice as many planned and ongoing Corridors in 2022 (79) compared to 2015 (33). I use this database to develop a spatially explicit framework to estimate indirect and cumulative biodiversity impacts from Development Corridors that considers existing pressures as well as potential new impacts. I then develop the Potential Impact Intensity metric to quantify the intensity of ecological impact due to either new infrastructure influence, existing pressures, or both. I calculate Potential Impact Intensity for all mapped planned and ongoing Development Corridors and show significant risks for Protected and Conserved Areas and Key Biodiversity Areas across all Africa. Moreover, I find that indirect and cumulative impacts are likely to be significantly larger than direct impacts, up to 200% more. Finally, I focus on East Africa and lead a collaborative and multidisciplinary review of Development Corridor implementation challenges in Kenya and Tanzania based on DCP field and desk-based research. Overall, in this thesis, I find that neither the scientific nor grey literature provides sufficiently robust approaches to treating indirect and cumulative biodiversity impacts for projects in Development Corridors. However, I show that by taking a systematic and nuanced spatial approach, we can measure the potential spatial extent and order of magnitude of indirect and cumulative impacts to support comprehensive design of impact mitigation measures. Actions can then be taken at a policy level or on the ground level. Policy level actions are those that take place independently of project approval but that could have a strong influence in the approval processes (e.g. impact assessment regulations). On the ground actions are specific mitigation measures elucidated through impact assessment (e.g., wildlife crossings). This research has important implications for the practice of biodiversity impact assessment, specifically in informing Strategic Environmental Assessments and their necessary interaction with project level Environmental Impact Assessments.