Planetary-scale changes due to human activities involve abrupt environmental alterations, which can particularly involve dramatic consequences in the aquatic systems because of the low dispersal ability of many species living there. In this study the physiological stress responses against non-lethal levels of common stressors for amphibian larvae, the most threatened group in the world, were evaluated. Changes in corticosterone, metabolic rate, oxidative stress, and immune system were measured in Pelobates cultripes tadpoles against non-lethal levels of salinity, herbicide (glyphosate), pH, temperature, and also against native (Dytiscus circumflexus) and invasive (Procambarus clarkii) predators. Results showed that salinity and herbicide caused the highest physiological imbalances in tadpoles. Tadpoles reduced corticosterone levels in the presence of natural predators but did not so against invasive predators, indicating a lack of innate recognition. Corticosterone and glutathione reductase were the most sensitive parameters to stress in this study. This study highlights the importance of incorporating physiological information onto conservation, ecological, and evolutionary studies. informacion[at]ebd.csic.es: Burraco & Gomez-Mestre. Physiological stress responses in amphibian larvae to multiple stressors reveal marked anthropogenic effects even below lethal levels. Physiol Biochem Zool DOI: 10.1086/688737