Feast or flee? Camera trapping reveals contrasting responses of generalist mammals (Meles meles and Apodemus sylvaticus) to an aposematic amphibian (Salamandra salamandra)

Abstract Predation risk is a major selective force shaping antipredator strategies, including aposematism. Although adult fire salamanders ( Salamandra salamandra ) are widely regarded as experiencing low predation pressure due to their conspicuous coloration and potent skin toxins, several vertebrates have been reported to consume them. The extent to which these species act as effective consumers of aposematic salamanders, however, remains poorly understood due to methodological constraints and the scarcity of direct observations. Here, we combined camera-trap monitoring with the experimental deployment of salamander carcasses to evaluate the roles of the European badger ( Meles meles ) and the wood mouse ( Apodemus sylvaticus ) as consumers of S. salamandra in a heterogeneous forest in northwestern Spain. Across two sampling periods (autumn 2024 and spring 2025), we recorded 440 independent events for A. sylvaticus (1090 total videos) and 36 for M. meles (83 total videos). Although badgers were frequently detected near their setts, none of the recorded events showed carcass manipulation or consumption. In contrast, wood mice interacted extensively with carcasses, with 37% of independent events involving biting or consumption and a significantly higher consumption rate in spring. These results identify A. sylvaticus as an important and previously underestimated consumer of aposematic salamanders, with seasonal variation likely driven by resource availability. Our findings highlight the value of experimental field approaches for quantifying consumption pressure on chemically defended amphibians and underscore the complexity of mammalian responses to aposematic defences.