Habitat loss or modification is the biggest threat to amphibians, which includes the introduction of non-native plants. Eucalyptus globulus trees have been introduced globally from its native Australia, and its negative effects on native species, including adult amphibians, have been documented. What about other stages? Iglesias-Carrasco et al. (2022) investigated with experiments on the effects of eucalypt leachates on tadpole behavior, morphology, growth, and immune response. Rana temporaria, Alytes obstetricans, and Pelophylax perezi tadpoles were raised in mesocosms with either native oak or exotic eucalypt leachates then exposed to predator cues. The authors found that while anti-predator responses were not significantly affected, tadpoles raised in eucalypt leachates were smaller and had weaker immune responses. Furthermore, the morphology of P. perezi tadpoles in eucalypt treatments were similar to the stress morphology of other species, which may affect the tadpoles’ ability to escape predators and jump in later development. Although species varied in responses, these results indicate that the poor nutrient content and high toxicity of Eucalyptus have strong impacts at critical early stages of frog development. Further studies are needed to fully understand the long-term fitness consequences of Eucalyptus monocultures.
