Reindeer habitat selection and movement change with cumulative impacts from mining and wind power development

Industrial expansion often occurs in landscapes already affected by multiple disturbances, leading to cumulative impacts on biodiversity and local communities. With the societal pressure for an rapid ‘green transition’, land-use changes intensifies, yet most impact assessments remain local and project-based, disregarding cumulative impacts. We conceptualized and disentangled key dimensions of cumulative impacts and integrated them within habitat selection, calving site selection, and movement analyses in a case study of reindeer and Sámi reindeer husbandry in Scandinavia. Using GPS data collected before, during, and after the construction of four wind power plants, we quantified the effects of mining, wind power development, and other infrastructure across snow-free seasons and behavioural processes. We found strong avoidance of mines and wind power plants, with zones of influence extending up to 5-10 km at landscape scale and up to 5 km at patch scale. Impacts were strongest during calving but also present in summer and autumn. Wind power plants affected movement by acting as semi-permeable barriers, with reindeer avoiding crossing them and moving faster and more directionally near turbines during construction. At patch scale, cumulative impacts of several wind power plants were evident during calving. Our results highlight the need for regional and integrative land-use planning that accounts for cumulative impacts from multiple existing and planned developments. The framework we present here provides a general approach to quantify zones of influence and cumulative impacts of multiple features and infrastructure types across landscapes and ecological processes.