Petter Andersson, Annika K. Jägerbrand

Light pollution poses a significant threat to nocturnal insects, yet our understanding of how insects are affected by lighting across ecosystems is limited. The purpose of this study was to investigate differences in light-induced attraction in abundance and diversity of moths in forest and grassland ecosystems. This study presents a novel comparison of moth attraction between these ecosystems using identical light traps with known lighting properties across 32 sites. We found significantly higher moth abundance and diversity (species richness) in forests compared to open grasslands, where environmental factors such as temperature and cloudiness had stronger effects on moth attraction in grasslands. Notably, moth families showed varying responses across ecosystems, suggesting potential sampling biases in light attraction studies. Our findings point to the need for ecosystem-specific approaches in light pollution mitigation strategies and provide a methodological approach for future research on the impacts of anthropogenic light on biodiversity. The results have important implications for conservation planning and the management of anthropogenic lighting in diverse landscapes.