Sparse data often make it difficult to track how climate change is affecting populations of insect species. A new study by the Technical University of Munich (TUM) and the German Centre for Integrative Biodiversity Research (iDiv) has now evaluated an extensive species mapping database (Artenschutzkartierung, ASK) organized by the Bavarian State Office for the Environment (LfU) and assessed the population trends of butterflies, dragonflies and grasshoppers in Bavaria since 1980. The main finding: heat-loving species have been increasing.