Global declines in amphibian populations are a significant conservation concern, and environmental contamination is likely a contributing driver. Although direct toxicity may be partly responsible, contaminants are often present at sub-lethal concentrations in the wild. Behavioural end-points are becoming an increasingly useful method to estimate the impact of contaminants, particularly if the behavioural responses manifest to affect individual fitness (i.e. survival, growth, or reproduction). In the wild, most animals are affected by multiple stressors, and determining how these interact to affect behaviour is critical for understanding the ecological implications of contaminant exposure. Here, we examined the individual and interactive effect of the heavy metal copper and the insecticide imidacloprid on mortality rates and anti-predator behaviours of spotted marsh frog (Limnodynastes tasmaniensis) tadpoles. This common species frequently occupies and breeds in contaminated stormwater and agricultural wetlands, where copper and imidacloprid are often present. These contaminants may alter behaviour via physiological and neurological pathways, as well as affecting how tadpoles respond to chemical cues. Tadpoles suffered unexpectedly high mortality rates when exposed to imidacloprid concentrations well below published LC50 concentrations. Only unexposed tadpoles significantly avoided predator cues. Copper and imidacloprid reduced swimming speed and distance, and escape responses, while increasing erratic swimming. We observed an interactive effect of imidacloprid and copper on erratic swimming, but in general imidacloprid and copper did not act synergistically. Our results suggest that as contaminants enter waterbodies, tadpoles will suffer considerable direct mortality, reduced foraging capacity, and increased susceptibility to predation. Our results provide the first evidence of imidacloprid affecting amphibian behaviour, and highlight both the adverse effects of copper and imidacloprid, and the importance of exploring the effect of multiple contaminants simultaneously.

全球两栖动物数量的下降是一个重要的保护问题，环境污染可能是造成这种情况的原因。尽管直接毒性可能是部分原因，但在野生环境中污染物通常以低于致死浓度存在。行为端点正在成为评估污染物影响的一种越来越有用的方法，尤其是如果行为响应表明会影响个体适应性（即生存，生长或繁殖）。在野外，大多数动物都会受到多种压力源的影响，因此确定它们如何相互作用以影响行为对于理解污染物暴露的生态影响至关重要。这里，塔斯马尼亚草）.。这种常见物种经常在受污染的雨水和农业湿地中繁殖和繁殖，那里经常存在铜和吡虫啉。这些污染物可能会通过生理和神经途径改变行为，并影响t对化学信号的反应。ida暴露于远低于公布的LC50浓度的吡虫啉浓度时，d的死亡率异常高。只有未暴露的t显着地避免了捕食者的暗示。铜和吡虫啉降低了游泳速度和距离，并逃脱了反应，同时增加了不稳定的游泳。我们观察到吡虫啉和铜对不稳定的游泳有交互作用，但总的来说吡虫啉和铜没有协同作用。我们的结果表明，随着污染物进入水体，将遭受可观的直接死亡率，减少觅食能力，并增加对捕食的敏感性。我们的结果提供了吡虫啉影响两栖动物行为的第一个证据，并突出了铜和吡虫啉的不利影响，以及同时探索多种污染物的影响的重要性。