Ecosystem-specific moth attraction to warm-coloured LED simulating road lighting conditions

Light pollution poses a significant threat to nocturnal insects, yet our understanding of how insects are affected by lighting across ecosystems remains limited. We investigated differences in light-induced attraction regarding abundance, richness and diversity of moths between forest and grassland ecosystems. This novel study presents the first multi-site comparison of moth attraction across ecosystems using warm-coloured LED lighting (3000 K) that simulates typical road lighting conditions in both spectral composition and intensity. Using identical light traps with characterised lighting properties across 32 sites, we found significantly higher moth abundance and diversity in forests compared to open grasslands, with stronger environmental effects on moth attraction in open grassland ecosystems. Even at the low light intensities used in our experiment, which is comparable to spill light from road lighting in natural environments, we found significant impacts on moth activity, which is concerning given their limited activity periods. Moth families exhibited varying attractions across ecosystems, suggesting potential sampling biases in light attraction studies. Our comprehensive light characterisation using real-world lighting conditions provides a standardised framework for future research on light pollution impacts. The findings demonstrate the need for ecosystem-specific approaches in light pollution mitigation strategies and have important implications for conservation across diverse landscapes.