Ingestion rates of Limnomysis benedeni, an invasive omnivorous crustacean feeding on various plankton species

Rising temperatures from global climate change alter the physiology of ectotherms, potentially shifting omnivores’ diets toward increased herbivory. However, the relevance and generality of these dietary shifts remain poorly understood in multispecies context due to a lack of studies using live prey. To address this critical knowledge gap, we performed experiments with the invasive mysid Limnomysis benedeni. We fed the mysids different combinations of autotrophic and heterotrophic prey species - varying in taxonomy and body sizes - across three experimental temperatures. We found that the ratio of autotrophic-to-heterotrophic prey consumption increased with warming. This was driven by an increase in autotrophic prey consumption and a decrease in heterotrophic prey consumption, regardless of the heterotrophic prey type. These findings suggest consistent changes in the functional role of L. benedeni under future climate warming. Our results provide a basis for future research in more complex, ecologically realistic settings, which can improve predictions of how warming-mediated impacts of invasive omnivores will affect freshwater communities and ecosystems.